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From: "Martin Liška" <mliska@suse.cz>
To: GCC Patches <gcc-patches@gcc.gnu.org>
Subject: [PATCH] libsanitizer: merge from master
Date: Thu, 13 May 2021 09:28:01 +0200	[thread overview]
Message-ID: <3236c6d4-85c2-ccfc-3cf1-64c673c45acc@suse.cz> (raw)

I'm planning to do merge from master twice a year.
This merge was tested on x86_64-linux-gnu and ppc64le-linux-gnu
and survives regression tests.

Pushed to master.
Thanks,
Martin

Merged revision: f58e0513dd95944b81ce7a6e7b49ba656de7d75f
---
  libsanitizer/MERGE                            |   2 +-
  libsanitizer/asan/asan_allocator.cpp          |  32 +-
  libsanitizer/asan/asan_descriptions.cpp       |  19 +-
  libsanitizer/asan/asan_descriptions.h         |  13 +-
  libsanitizer/asan/asan_errors.cpp             |   7 +-
  libsanitizer/asan/asan_fake_stack.cpp         |   2 +-
  libsanitizer/asan/asan_fuchsia.cpp            |   2 +-
  libsanitizer/asan/asan_globals.cpp            |  19 +
  libsanitizer/asan/asan_interceptors.cpp       |  41 +-
  libsanitizer/asan/asan_interceptors.h         |  21 +-
  libsanitizer/asan/asan_linux.cpp              |   3 +-
  libsanitizer/asan/asan_mapping.h              |  25 +-
  libsanitizer/asan/asan_new_delete.cpp         |   2 +-
  libsanitizer/asan/asan_poisoning.cpp          |   2 +-
  libsanitizer/asan/asan_posix.cpp              |   2 +-
  libsanitizer/asan/asan_rtl.cpp                |  20 +-
  libsanitizer/asan/asan_stack.h                |   9 -
  libsanitizer/asan/asan_thread.cpp             |  51 +-
  libsanitizer/asan/asan_thread.h               |   6 +-
  libsanitizer/asan/asan_win.cpp                |   2 +-
  libsanitizer/builtins/assembly.h              |  98 +++-
  libsanitizer/hwasan/hwasan.cpp                |  19 +-
  libsanitizer/hwasan/hwasan.h                  |  41 +-
  libsanitizer/hwasan/hwasan_allocator.cpp      |  28 +-
  libsanitizer/hwasan/hwasan_allocator.h        |  19 +-
  libsanitizer/hwasan/hwasan_checks.h           |   5 +-
  libsanitizer/hwasan/hwasan_dynamic_shadow.cpp |  16 +-
  libsanitizer/hwasan/hwasan_flags.h            |   2 +
  libsanitizer/hwasan/hwasan_flags.inc          |   9 +
  libsanitizer/hwasan/hwasan_interceptors.cpp   |   3 +-
  .../hwasan/hwasan_interceptors_vfork.S        |   3 +
  .../hwasan/hwasan_interface_internal.h        |   3 +
  libsanitizer/hwasan/hwasan_linux.cpp          |  41 +-
  libsanitizer/hwasan/hwasan_mapping.h          |   2 +
  libsanitizer/hwasan/hwasan_memintrinsics.cpp  |   4 +-
  libsanitizer/hwasan/hwasan_new_delete.cpp     |  39 ++
  libsanitizer/hwasan/hwasan_report.cpp         |  26 +-
  libsanitizer/hwasan/hwasan_setjmp.S           |   6 +
  .../hwasan/hwasan_tag_mismatch_aarch64.S      |   6 +
  libsanitizer/hwasan/hwasan_thread.cpp         |  15 +-
  libsanitizer/hwasan/hwasan_thread.h           |   4 +-
  libsanitizer/hwasan/hwasan_thread_list.h      |  90 ++--
  .../include/sanitizer/common_interface_defs.h |   3 +
  .../include/sanitizer/dfsan_interface.h       |  16 +
  .../include/sanitizer/hwasan_interface.h      |   3 +
  .../include/sanitizer/memprof_interface.h     |   5 +
  .../include/sanitizer/tsan_interface.h        |  17 +-
  .../include/sanitizer/tsan_interface_atomic.h |   2 +-
  .../interception/interception_linux.cpp       |   6 +-
  .../interception/interception_linux.h         |   6 +-
  .../interception/interception_win.cpp         |   6 +-
  libsanitizer/lsan/lsan_allocator.cpp          |  26 +-
  libsanitizer/lsan/lsan_allocator.h            |   2 +-
  libsanitizer/lsan/lsan_common.cpp             | 234 ++++++---
  libsanitizer/lsan/lsan_common.h               |   9 +-
  libsanitizer/lsan/lsan_common_fuchsia.cpp     |   4 +-
  libsanitizer/lsan/lsan_fuchsia.h              |   2 +-
  libsanitizer/lsan/lsan_interceptors.cpp       |   2 +-
  libsanitizer/lsan/lsan_posix.cpp              |   6 +-
  libsanitizer/lsan/lsan_thread.cpp             |   2 +-
  .../sanitizer_allocator_combined.h            |   4 +-
  .../sanitizer_allocator_primary32.h           |   3 +-
  .../sanitizer_allocator_primary64.h           |  93 +++-
  .../sanitizer_allocator_size_class_map.h      |   2 +-
  .../sanitizer_atomic_clang_mips.h             |   8 +-
  .../sanitizer_chained_origin_depot.cpp        | 108 +++++
  .../sanitizer_chained_origin_depot.h          |  88 ++++
  .../sanitizer_common/sanitizer_common.cpp     |  10 +-
  .../sanitizer_common/sanitizer_common.h       |  82 +++-
  .../sanitizer_common_interceptors.inc         |  19 +-
  .../sanitizer_common_interceptors_ioctl.inc   |   6 +-
  ...er_common_interceptors_vfork_aarch64.inc.S |   5 +
  .../sanitizer_common_interface.inc            |   1 +
  .../sanitizer_common_libcdep.cpp              |   7 +-
  .../sanitizer_common/sanitizer_file.cpp       |  13 +
  .../sanitizer_common/sanitizer_file.h         |   1 +
  .../sanitizer_common/sanitizer_flags.cpp      |   7 +
  .../sanitizer_common/sanitizer_flags.inc      |   2 +
  .../sanitizer_common/sanitizer_fuchsia.cpp    |  72 +--
  .../sanitizer_interface_internal.h            |   4 +
  .../sanitizer_internal_defs.h                 |   3 +
  .../sanitizer_common/sanitizer_libignore.cpp  |   2 +-
  .../sanitizer_common/sanitizer_linux.cpp      |  72 +--
  .../sanitizer_common/sanitizer_linux.h        |   3 +-
  .../sanitizer_linux_libcdep.cpp               | 447 ++++++++++--------
  .../sanitizer_local_address_space_view.h      |   2 +-
  .../sanitizer_common/sanitizer_mac.cpp        | 141 +++++-
  libsanitizer/sanitizer_common/sanitizer_mac.h |  37 --
  .../sanitizer_common/sanitizer_malloc_mac.inc |   6 +-
  .../sanitizer_common/sanitizer_netbsd.cpp     |   6 +
  .../sanitizer_common/sanitizer_platform.h     |  27 +-
  .../sanitizer_platform_interceptors.h         | 113 +++--
  .../sanitizer_platform_limits_freebsd.cpp     |   3 +
  .../sanitizer_platform_limits_linux.cpp       |   7 +-
  .../sanitizer_platform_limits_posix.cpp       |  85 ++--
  .../sanitizer_platform_limits_posix.h         |   4 +-
  .../sanitizer_common/sanitizer_posix.cpp      |   4 +-
  .../sanitizer_common/sanitizer_posix.h        |   4 +
  .../sanitizer_posix_libcdep.cpp               |   2 +-
  .../sanitizer_common/sanitizer_printf.cpp     |  57 ++-
  .../sanitizer_procmaps_common.cpp             |   2 +-
  .../sanitizer_procmaps_mac.cpp                |   4 +-
  .../sanitizer_procmaps_solaris.cpp            |   4 +-
  .../sanitizer_common/sanitizer_ptrauth.h      |  20 +-
  .../sanitizer_common/sanitizer_stackdepot.cpp |   3 +-
  .../sanitizer_common/sanitizer_stacktrace.cpp |  20 +-
  .../sanitizer_common/sanitizer_stacktrace.h   |   2 -
  .../sanitizer_stacktrace_libcdep.cpp          |   8 +-
  .../sanitizer_stoptheworld_linux_libcdep.cpp  |   5 +
  .../sanitizer_suppressions.cpp                |   4 +-
  .../sanitizer_symbolizer_libcdep.cpp          |   2 +-
  .../sanitizer_symbolizer_markup.cpp           |   4 +
  .../sanitizer_symbolizer_posix_libcdep.cpp    |  11 +-
  .../sanitizer_symbolizer_report.cpp           |   6 +-
  .../sanitizer_symbolizer_win.cpp              |  18 +-
  .../sanitizer_termination.cpp                 |  33 +-
  .../sanitizer_thread_registry.cpp             |  14 +-
  .../sanitizer_thread_registry.h               |   7 +-
  .../sanitizer_tls_get_addr.cpp                |  79 ++--
  .../sanitizer_common/sanitizer_tls_get_addr.h |  21 +-
  .../sanitizer_common/sanitizer_unwind_win.cpp |   7 +
  .../sanitizer_common/sanitizer_win.cpp        |  84 ++--
  libsanitizer/tsan/tsan_clock.cpp              |  37 +-
  libsanitizer/tsan/tsan_clock.h                |  16 +-
  libsanitizer/tsan/tsan_defs.h                 |   2 -
  libsanitizer/tsan/tsan_dense_alloc.h          |  32 +-
  libsanitizer/tsan/tsan_external.cpp           |   4 +-
  libsanitizer/tsan/tsan_interceptors_mac.cpp   |   1 +
  libsanitizer/tsan/tsan_interceptors_posix.cpp | 149 ++++--
  libsanitizer/tsan/tsan_interface.cpp          |   8 +-
  libsanitizer/tsan/tsan_interface.h            |   9 +-
  libsanitizer/tsan/tsan_interface_inl.h        |  22 +-
  libsanitizer/tsan/tsan_mman.cpp               |   2 +-
  libsanitizer/tsan/tsan_platform.h             | 121 ++++-
  libsanitizer/tsan/tsan_platform_linux.cpp     |  23 +-
  libsanitizer/tsan/tsan_platform_mac.cpp       |   9 +-
  libsanitizer/tsan/tsan_platform_posix.cpp     |   2 +-
  libsanitizer/tsan/tsan_report.cpp             |  14 +-
  libsanitizer/tsan/tsan_rtl.cpp                | 129 +++--
  libsanitizer/tsan/tsan_rtl.h                  |  11 +-
  libsanitizer/tsan/tsan_rtl_mutex.cpp          |  25 +-
  libsanitizer/tsan/tsan_rtl_ppc64.S            |   1 -
  libsanitizer/tsan/tsan_rtl_report.cpp         |  56 ++-
  libsanitizer/tsan/tsan_rtl_thread.cpp         |  13 +-
  libsanitizer/tsan/tsan_sync.cpp               |   4 +-
  libsanitizer/tsan/tsan_sync.h                 |   8 +-
  libsanitizer/ubsan/ubsan_diag.cpp             |   8 +-
  libsanitizer/ubsan/ubsan_flags.cpp            |   1 -
  libsanitizer/ubsan/ubsan_handlers.cpp         |  15 -
  libsanitizer/ubsan/ubsan_handlers.h           |   8 -
  libsanitizer/ubsan/ubsan_init.cpp             |   9 +
  libsanitizer/ubsan/ubsan_monitor.cpp          |   6 +-
  libsanitizer/ubsan/ubsan_platform.h           |   4 +-
  153 files changed, 2538 insertions(+), 1239 deletions(-)
  create mode 100644 libsanitizer/sanitizer_common/sanitizer_chained_origin_depot.cpp
  create mode 100644 libsanitizer/sanitizer_common/sanitizer_chained_origin_depot.h

diff --git a/libsanitizer/MERGE b/libsanitizer/MERGE
index 0fb64a9567c..c4731d0866c 100644
--- a/libsanitizer/MERGE
+++ b/libsanitizer/MERGE
@@ -1,4 +1,4 @@
-6e7dd1e3e1170080b76b5dcc5716bdd974343233
+f58e0513dd95944b81ce7a6e7b49ba656de7d75f
  
  The first line of this file holds the git revision number of the
  last merge done from the master library sources.
diff --git a/libsanitizer/asan/asan_allocator.cpp b/libsanitizer/asan/asan_allocator.cpp
index 58b496a3ca4..7c8bb504332 100644
--- a/libsanitizer/asan/asan_allocator.cpp
+++ b/libsanitizer/asan/asan_allocator.cpp
@@ -476,7 +476,7 @@ struct Allocator {
        return false;
      if (m->Beg() != addr) return false;
      AsanThread *t = GetCurrentThread();
-    m->SetAllocContext(t ? t->tid() : 0, StackDepotPut(*stack));
+    m->SetAllocContext(t ? t->tid() : kMainTid, StackDepotPut(*stack));
      return true;
    }
  
@@ -570,7 +570,7 @@ struct Allocator {
      m->SetUsedSize(size);
      m->user_requested_alignment_log = user_requested_alignment_log;
  
-    m->SetAllocContext(t ? t->tid() : 0, StackDepotPut(*stack));
+    m->SetAllocContext(t ? t->tid() : kMainTid, StackDepotPut(*stack));
  
      uptr size_rounded_down_to_granularity =
          RoundDownTo(size, SHADOW_GRANULARITY);
@@ -1183,6 +1183,34 @@ IgnoreObjectResult IgnoreObjectLocked(const void *p) {
    m->lsan_tag = __lsan::kIgnored;
    return kIgnoreObjectSuccess;
  }
+
+void GetAdditionalThreadContextPtrs(ThreadContextBase *tctx, void *ptrs) {
+  // Look for the arg pointer of threads that have been created or are running.
+  // This is necessary to prevent false positive leaks due to the AsanThread
+  // holding the only live reference to a heap object.  This can happen because
+  // the `pthread_create()` interceptor doesn't wait for the child thread to
+  // start before returning and thus loosing the the only live reference to the
+  // heap object on the stack.
+
+  __asan::AsanThreadContext *atctx =
+      reinterpret_cast<__asan::AsanThreadContext *>(tctx);
+  __asan::AsanThread *asan_thread = atctx->thread;
+
+  // Note ThreadStatusRunning is required because there is a small window where
+  // the thread status switches to `ThreadStatusRunning` but the `arg` pointer
+  // still isn't on the stack yet.
+  if (atctx->status != ThreadStatusCreated &&
+      atctx->status != ThreadStatusRunning)
+    return;
+
+  uptr thread_arg = reinterpret_cast<uptr>(asan_thread->get_arg());
+  if (!thread_arg)
+    return;
+
+  auto ptrsVec = reinterpret_cast<InternalMmapVector<uptr> *>(ptrs);
+  ptrsVec->push_back(thread_arg);
+}
+
  }  // namespace __lsan
  
  // ---------------------- Interface ---------------- {{{1
diff --git a/libsanitizer/asan/asan_descriptions.cpp b/libsanitizer/asan/asan_descriptions.cpp
index 153c874a4e7..2ba8a02f841 100644
--- a/libsanitizer/asan/asan_descriptions.cpp
+++ b/libsanitizer/asan/asan_descriptions.cpp
@@ -44,11 +44,11 @@ void DescribeThread(AsanThreadContext *context) {
    CHECK(context);
    asanThreadRegistry().CheckLocked();
    // No need to announce the main thread.
-  if (context->tid == 0 || context->announced) {
+  if (context->tid == kMainTid || context->announced) {
      return;
    }
    context->announced = true;
-  InternalScopedString str(1024);
+  InternalScopedString str;
    str.append("Thread %s", AsanThreadIdAndName(context).c_str());
    if (context->parent_tid == kInvalidTid) {
      str.append(" created by unknown thread\n");
@@ -77,7 +77,6 @@ static bool GetShadowKind(uptr addr, ShadowKind *shadow_kind) {
    } else if (AddrIsInLowShadow(addr)) {
      *shadow_kind = kShadowKindLow;
    } else {
-    CHECK(0 && "Address is not in memory and not in shadow?");
      return false;
    }
    return true;
@@ -126,7 +125,7 @@ static void GetAccessToHeapChunkInformation(ChunkAccess *descr,
  
  static void PrintHeapChunkAccess(uptr addr, const ChunkAccess &descr) {
    Decorator d;
-  InternalScopedString str(4096);
+  InternalScopedString str;
    str.append("%s", d.Location());
    switch (descr.access_type) {
      case kAccessTypeLeft:
@@ -243,7 +242,7 @@ static void PrintAccessAndVarIntersection(const StackVarDescr &var, uptr addr,
      else if (addr >= prev_var_end && addr - prev_var_end >= var.beg - addr_end)
        pos_descr = "underflows";
    }
-  InternalScopedString str(1024);
+  InternalScopedString str;
    str.append("    [%zd, %zd)", var.beg, var_end);
    // Render variable name.
    str.append(" '");
@@ -276,7 +275,7 @@ bool DescribeAddressIfStack(uptr addr, uptr access_size) {
  // Global descriptions
  static void DescribeAddressRelativeToGlobal(uptr addr, uptr access_size,
                                              const __asan_global &g) {
-  InternalScopedString str(4096);
+  InternalScopedString str;
    Decorator d;
    str.append("%s", d.Location());
    if (addr < g.beg) {
@@ -464,7 +463,13 @@ AddressDescription::AddressDescription(uptr addr, uptr access_size,
      return;
    }
    data.kind = kAddressKindWild;
-  addr = 0;
+  data.wild.addr = addr;
+  data.wild.access_size = access_size;
+}
+
+void WildAddressDescription::Print() const {
+  Printf("Address %p is a wild pointer inside of access range of size %p.\n",
+         addr, access_size);
  }
  
  void PrintAddressDescription(uptr addr, uptr access_size,
diff --git a/libsanitizer/asan/asan_descriptions.h b/libsanitizer/asan/asan_descriptions.h
index ee0e2061559..650e2eb9173 100644
--- a/libsanitizer/asan/asan_descriptions.h
+++ b/libsanitizer/asan/asan_descriptions.h
@@ -146,6 +146,13 @@ struct StackAddressDescription {
  bool GetStackAddressInformation(uptr addr, uptr access_size,
                                  StackAddressDescription *descr);
  
+struct WildAddressDescription {
+  uptr addr;
+  uptr access_size;
+
+  void Print() const;
+};
+
  struct GlobalAddressDescription {
    uptr addr;
    // Assume address is close to at most four globals.
@@ -193,7 +200,7 @@ class AddressDescription {
        HeapAddressDescription heap;
        StackAddressDescription stack;
        GlobalAddressDescription global;
-      uptr addr;
+      WildAddressDescription wild;
      };
    };
  
@@ -211,7 +218,7 @@ class AddressDescription {
    uptr Address() const {
      switch (data.kind) {
        case kAddressKindWild:
-        return data.addr;
+        return data.wild.addr;
        case kAddressKindShadow:
          return data.shadow.addr;
        case kAddressKindHeap:
@@ -226,7 +233,7 @@ class AddressDescription {
    void Print(const char *bug_descr = nullptr) const {
      switch (data.kind) {
        case kAddressKindWild:
-        Printf("Address %p is a wild pointer.\n", data.addr);
+        data.wild.Print();
          return;
        case kAddressKindShadow:
          return data.shadow.Print();
diff --git a/libsanitizer/asan/asan_errors.cpp b/libsanitizer/asan/asan_errors.cpp
index 541c6e0353b..e68e6971f96 100644
--- a/libsanitizer/asan/asan_errors.cpp
+++ b/libsanitizer/asan/asan_errors.cpp
@@ -343,7 +343,8 @@ void ErrorODRViolation::Print() {
    Report("ERROR: AddressSanitizer: %s (%p):\n", scariness.GetDescription(),
           global1.beg);
    Printf("%s", d.Default());
-  InternalScopedString g1_loc(256), g2_loc(256);
+  InternalScopedString g1_loc;
+  InternalScopedString g2_loc;
    PrintGlobalLocation(&g1_loc, global1);
    PrintGlobalLocation(&g2_loc, global2);
    Printf("  [1] size=%zd '%s' %s\n", global1.size,
@@ -360,7 +361,7 @@ void ErrorODRViolation::Print() {
    Report(
        "HINT: if you don't care about these errors you may set "
        "ASAN_OPTIONS=detect_odr_violation=0\n");
-  InternalScopedString error_msg(256);
+  InternalScopedString error_msg;
    error_msg.append("%s: global '%s' at %s", scariness.GetDescription(),
                     MaybeDemangleGlobalName(global1.name), g1_loc.data());
    ReportErrorSummary(error_msg.data());
@@ -554,7 +555,7 @@ static void PrintShadowMemoryForAddress(uptr addr) {
    uptr shadow_addr = MemToShadow(addr);
    const uptr n_bytes_per_row = 16;
    uptr aligned_shadow = shadow_addr & ~(n_bytes_per_row - 1);
-  InternalScopedString str(4096 * 8);
+  InternalScopedString str;
    str.append("Shadow bytes around the buggy address:\n");
    for (int i = -5; i <= 5; i++) {
      uptr row_shadow_addr = aligned_shadow + i * n_bytes_per_row;
diff --git a/libsanitizer/asan/asan_fake_stack.cpp b/libsanitizer/asan/asan_fake_stack.cpp
index 295e6debc96..1f873fec7d7 100644
--- a/libsanitizer/asan/asan_fake_stack.cpp
+++ b/libsanitizer/asan/asan_fake_stack.cpp
@@ -65,7 +65,7 @@ FakeStack *FakeStack::Create(uptr stack_size_log) {
  void FakeStack::Destroy(int tid) {
    PoisonAll(0);
    if (Verbosity() >= 2) {
-    InternalScopedString str(kNumberOfSizeClasses * 50);
+    InternalScopedString str;
      for (uptr class_id = 0; class_id < kNumberOfSizeClasses; class_id++)
        str.append("%zd: %zd/%zd; ", class_id, hint_position_[class_id],
                   NumberOfFrames(stack_size_log(), class_id));
diff --git a/libsanitizer/asan/asan_fuchsia.cpp b/libsanitizer/asan/asan_fuchsia.cpp
index 6c61344f87c..b0c7255144a 100644
--- a/libsanitizer/asan/asan_fuchsia.cpp
+++ b/libsanitizer/asan/asan_fuchsia.cpp
@@ -81,7 +81,7 @@ void AsanTSDInit(void (*destructor)(void *tsd)) {
  void PlatformTSDDtor(void *tsd) { UNREACHABLE(__func__); }
  
  static inline size_t AsanThreadMmapSize() {
-  return RoundUpTo(sizeof(AsanThread), PAGE_SIZE);
+  return RoundUpTo(sizeof(AsanThread), _zx_system_get_page_size());
  }
  
  struct AsanThread::InitOptions {
diff --git a/libsanitizer/asan/asan_globals.cpp b/libsanitizer/asan/asan_globals.cpp
index e045c31cd1c..9d7dbc6f264 100644
--- a/libsanitizer/asan/asan_globals.cpp
+++ b/libsanitizer/asan/asan_globals.cpp
@@ -154,6 +154,23 @@ static void CheckODRViolationViaIndicator(const Global *g) {
    }
  }
  
+// Check ODR violation for given global G by checking if it's already poisoned.
+// We use this method in case compiler doesn't use private aliases for global
+// variables.
+static void CheckODRViolationViaPoisoning(const Global *g) {
+  if (__asan_region_is_poisoned(g->beg, g->size_with_redzone)) {
+    // This check may not be enough: if the first global is much larger
+    // the entire redzone of the second global may be within the first global.
+    for (ListOfGlobals *l = list_of_all_globals; l; l = l->next) {
+      if (g->beg == l->g->beg &&
+          (flags()->detect_odr_violation >= 2 || g->size != l->g->size) &&
+          !IsODRViolationSuppressed(g->name))
+        ReportODRViolation(g, FindRegistrationSite(g),
+                           l->g, FindRegistrationSite(l->g));
+    }
+  }
+}
+
  // Clang provides two different ways for global variables protection:
  // it can poison the global itself or its private alias. In former
  // case we may poison same symbol multiple times, that can help us to
@@ -199,6 +216,8 @@ static void RegisterGlobal(const Global *g) {
      // where two globals with the same name are defined in different modules.
      if (UseODRIndicator(g))
        CheckODRViolationViaIndicator(g);
+    else
+      CheckODRViolationViaPoisoning(g);
    }
    if (CanPoisonMemory())
      PoisonRedZones(*g);
diff --git a/libsanitizer/asan/asan_interceptors.cpp b/libsanitizer/asan/asan_interceptors.cpp
index 4e68b3b0b47..9db7db89fa1 100644
--- a/libsanitizer/asan/asan_interceptors.cpp
+++ b/libsanitizer/asan/asan_interceptors.cpp
@@ -191,20 +191,11 @@ DECLARE_REAL_AND_INTERCEPTOR(void, free, void *)
  #include "sanitizer_common/sanitizer_common_syscalls.inc"
  #include "sanitizer_common/sanitizer_syscalls_netbsd.inc"
  
-struct ThreadStartParam {
-  atomic_uintptr_t t;
-  atomic_uintptr_t is_registered;
-};
-
  #if ASAN_INTERCEPT_PTHREAD_CREATE
  static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
-  ThreadStartParam *param = reinterpret_cast<ThreadStartParam *>(arg);
-  AsanThread *t = nullptr;
-  while ((t = reinterpret_cast<AsanThread *>(
-              atomic_load(&param->t, memory_order_acquire))) == nullptr)
-    internal_sched_yield();
+  AsanThread *t = (AsanThread *)arg;
    SetCurrentThread(t);
-  return t->ThreadStart(GetTid(), &param->is_registered);
+  return t->ThreadStart(GetTid());
  }
  
  INTERCEPTOR(int, pthread_create, void *thread,
@@ -217,9 +208,11 @@ INTERCEPTOR(int, pthread_create, void *thread,
    int detached = 0;
    if (attr)
      REAL(pthread_attr_getdetachstate)(attr, &detached);
-  ThreadStartParam param;
-  atomic_store(&param.t, 0, memory_order_relaxed);
-  atomic_store(&param.is_registered, 0, memory_order_relaxed);
+
+  u32 current_tid = GetCurrentTidOrInvalid();
+  AsanThread *t =
+      AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
+
    int result;
    {
      // Ignore all allocations made by pthread_create: thread stack/TLS may be
@@ -229,21 +222,13 @@ INTERCEPTOR(int, pthread_create, void *thread,
  #if CAN_SANITIZE_LEAKS
      __lsan::ScopedInterceptorDisabler disabler;
  #endif
-    result = REAL(pthread_create)(thread, attr, asan_thread_start, &param);
+    result = REAL(pthread_create)(thread, attr, asan_thread_start, t);
    }
-  if (result == 0) {
-    u32 current_tid = GetCurrentTidOrInvalid();
-    AsanThread *t =
-        AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
-    atomic_store(&param.t, reinterpret_cast<uptr>(t), memory_order_release);
-    // Wait until the AsanThread object is initialized and the ThreadRegistry
-    // entry is in "started" state. One reason for this is that after this
-    // interceptor exits, the child thread's stack may be the only thing holding
-    // the |arg| pointer. This may cause LSan to report a leak if leak checking
-    // happens at a point when the interceptor has already exited, but the stack
-    // range for the child thread is not yet known.
-    while (atomic_load(&param.is_registered, memory_order_acquire) == 0)
-      internal_sched_yield();
+  if (result != 0) {
+    // If the thread didn't start delete the AsanThread to avoid leaking it.
+    // Note AsanThreadContexts never get destroyed so the AsanThreadContext
+    // that was just created for the AsanThread is wasted.
+    t->Destroy();
    }
    return result;
  }
diff --git a/libsanitizer/asan/asan_interceptors.h b/libsanitizer/asan/asan_interceptors.h
index 56dc34b7d93..e8c58c2dc6b 100644
--- a/libsanitizer/asan/asan_interceptors.h
+++ b/libsanitizer/asan/asan_interceptors.h
@@ -60,7 +60,7 @@ void InitializePlatformInterceptors();
  # define ASAN_USE_ALIAS_ATTRIBUTE_FOR_INDEX 0
  #endif
  
-#if (SANITIZER_LINUX && !SANITIZER_ANDROID) || SANITIZER_SOLARIS
+#if SANITIZER_GLIBC || SANITIZER_SOLARIS
  # define ASAN_INTERCEPT_SWAPCONTEXT 1
  #else
  # define ASAN_INTERCEPT_SWAPCONTEXT 0
@@ -72,7 +72,7 @@ void InitializePlatformInterceptors();
  # define ASAN_INTERCEPT_SIGLONGJMP 0
  #endif
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
+#if SANITIZER_GLIBC
  # define ASAN_INTERCEPT___LONGJMP_CHK 1
  #else
  # define ASAN_INTERCEPT___LONGJMP_CHK 0
@@ -81,12 +81,7 @@ void InitializePlatformInterceptors();
  #if ASAN_HAS_EXCEPTIONS && !SANITIZER_WINDOWS && !SANITIZER_SOLARIS && \
      !SANITIZER_NETBSD
  # define ASAN_INTERCEPT___CXA_THROW 1
-# if ! defined(ASAN_HAS_CXA_RETHROW_PRIMARY_EXCEPTION) \
-     || ASAN_HAS_CXA_RETHROW_PRIMARY_EXCEPTION
-#   define ASAN_INTERCEPT___CXA_RETHROW_PRIMARY_EXCEPTION 1
-# else
-#   define ASAN_INTERCEPT___CXA_RETHROW_PRIMARY_EXCEPTION 0
-# endif
+# define ASAN_INTERCEPT___CXA_RETHROW_PRIMARY_EXCEPTION 1
  # if defined(_GLIBCXX_SJLJ_EXCEPTIONS) || (SANITIZER_IOS && defined(__arm__))
  #  define ASAN_INTERCEPT__UNWIND_SJLJ_RAISEEXCEPTION 1
  # else
@@ -111,7 +106,7 @@ void InitializePlatformInterceptors();
  # define ASAN_INTERCEPT_ATEXIT 0
  #endif
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
+#if SANITIZER_GLIBC
  # define ASAN_INTERCEPT___STRDUP 1
  #else
  # define ASAN_INTERCEPT___STRDUP 0
@@ -139,10 +134,10 @@ DECLARE_REAL(uptr, strnlen, const char *s, uptr maxlen)
  DECLARE_REAL(char*, strstr, const char *s1, const char *s2)
  
  #if !SANITIZER_MAC
-#define ASAN_INTERCEPT_FUNC(name)                                         \
-  do {                                                                    \
-    if (!INTERCEPT_FUNCTION(name))                                        \
-      VReport(1, "AddressSanitizer: failed to intercept '%s'\n'", #name); \
+#define ASAN_INTERCEPT_FUNC(name)                                        \
+  do {                                                                   \
+    if (!INTERCEPT_FUNCTION(name))                                       \
+      VReport(1, "AddressSanitizer: failed to intercept '%s'\n", #name); \
    } while (0)
  #define ASAN_INTERCEPT_FUNC_VER(name, ver)                                  \
    do {                                                                      \
diff --git a/libsanitizer/asan/asan_linux.cpp b/libsanitizer/asan/asan_linux.cpp
index fb1a442b3d4..4bcbe5d02e3 100644
--- a/libsanitizer/asan/asan_linux.cpp
+++ b/libsanitizer/asan/asan_linux.cpp
@@ -55,6 +55,7 @@ extern Elf_Dyn _DYNAMIC;
  #else
  #include <sys/ucontext.h>
  #include <link.h>
+extern ElfW(Dyn) _DYNAMIC[];
  #endif
  
  // x86-64 FreeBSD 9.2 and older define 'ucontext_t' incorrectly in
@@ -84,7 +85,7 @@ bool IsSystemHeapAddress (uptr addr) { return false; }
  
  void *AsanDoesNotSupportStaticLinkage() {
    // This will fail to link with -static.
-  return &_DYNAMIC;  // defined in link.h
+  return &_DYNAMIC;
  }
  
  #if ASAN_PREMAP_SHADOW
diff --git a/libsanitizer/asan/asan_mapping.h b/libsanitizer/asan/asan_mapping.h
index a7136de60d2..455e2364cd0 100644
--- a/libsanitizer/asan/asan_mapping.h
+++ b/libsanitizer/asan/asan_mapping.h
@@ -72,6 +72,13 @@
  // || `[0x2000000000, 0x23ffffffff]` || LowShadow  ||
  // || `[0x0000000000, 0x1fffffffff]` || LowMem     ||
  //
+// Default Linux/RISCV64 Sv39 mapping:
+// || `[0x1555550000, 0x3fffffffff]` || HighMem    ||
+// || `[0x0fffffa000, 0x1555555fff]` || HighShadow ||
+// || `[0x0effffa000, 0x0fffff9fff]` || ShadowGap  ||
+// || `[0x0d55550000, 0x0effff9fff]` || LowShadow  ||
+// || `[0x0000000000, 0x0d5554ffff]` || LowMem     ||
+//
  // Default Linux/AArch64 (39-bit VMA) mapping:
  // || `[0x2000000000, 0x7fffffffff]` || highmem    ||
  // || `[0x1400000000, 0x1fffffffff]` || highshadow ||
@@ -79,20 +86,6 @@
  // || `[0x1000000000, 0x11ffffffff]` || lowshadow  ||
  // || `[0x0000000000, 0x0fffffffff]` || lowmem     ||
  //
-// RISC-V has only 38 bits for task size
-// Low mem size is set with kRiscv64_ShadowOffset64 in
-// compiler-rt/lib/asan/asan_allocator.h and in
-// llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp with
-// kRiscv64_ShadowOffset64, High mem top border is set with
-// GetMaxVirtualAddress() in
-// compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
-// Default Linux/RISCV64 Sv39/Sv48 mapping:
-// || `[0x000820000000, 0x003fffffffff]` || HighMem    ||
-// || `[0x000124000000, 0x00081fffffff]` || HighShadow ||
-// || `[0x000024000000, 0x000123ffffff]` || ShadowGap  ||
-// || `[0x000020000000, 0x000023ffffff]` || LowShadow  ||
-// || `[0x000000000000, 0x00001fffffff]` || LowMem     ||
-//
  // Default Linux/AArch64 (42-bit VMA) mapping:
  // || `[0x10000000000, 0x3ffffffffff]` || highmem    ||
  // || `[0x0a000000000, 0x0ffffffffff]` || highshadow ||
@@ -175,10 +168,10 @@ static const u64 kDefaultShadowOffset64 = 1ULL << 44;
  static const u64 kDefaultShort64bitShadowOffset =
      0x7FFFFFFF & (~0xFFFULL << kDefaultShadowScale);  // < 2G.
  static const u64 kAArch64_ShadowOffset64 = 1ULL << 36;
-static const u64 kRiscv64_ShadowOffset64 = 0x20000000;
+static const u64 kRiscv64_ShadowOffset64 = 0xd55550000;
  static const u64 kMIPS32_ShadowOffset32 = 0x0aaa0000;
  static const u64 kMIPS64_ShadowOffset64 = 1ULL << 37;
-static const u64 kPPC64_ShadowOffset64 = 1ULL << 41;
+static const u64 kPPC64_ShadowOffset64 = 1ULL << 44;
  static const u64 kSystemZ_ShadowOffset64 = 1ULL << 52;
  static const u64 kSPARC64_ShadowOffset64 = 1ULL << 43;  // 0x80000000000
  static const u64 kFreeBSD_ShadowOffset32 = 1ULL << 30;  // 0x40000000
diff --git a/libsanitizer/asan/asan_new_delete.cpp b/libsanitizer/asan/asan_new_delete.cpp
index 5dfcc00fd5d..92a8648452b 100644
--- a/libsanitizer/asan/asan_new_delete.cpp
+++ b/libsanitizer/asan/asan_new_delete.cpp
@@ -45,7 +45,7 @@ COMMENT_EXPORT("??_V@YAXPAX@Z")                   // operator delete[]
  #endif
  #undef COMMENT_EXPORT
  #else
-#define CXX_OPERATOR_ATTRIBUTE INTERCEPTOR_ATTRIBUTE
+#define CXX_OPERATOR_ATTRIBUTE INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
  #endif
  
  using namespace __asan;
diff --git a/libsanitizer/asan/asan_poisoning.cpp b/libsanitizer/asan/asan_poisoning.cpp
index 44f872ef619..fa149ecfde6 100644
--- a/libsanitizer/asan/asan_poisoning.cpp
+++ b/libsanitizer/asan/asan_poisoning.cpp
@@ -364,7 +364,7 @@ void __sanitizer_annotate_contiguous_container(const void *beg_p,
                                                   &stack);
    }
    CHECK_LE(end - beg,
-           FIRST_32_SECOND_64(1UL << 30, 1ULL << 34)); // Sanity check.
+           FIRST_32_SECOND_64(1UL << 30, 1ULL << 40)); // Sanity check.
  
    uptr a = RoundDownTo(Min(old_mid, new_mid), granularity);
    uptr c = RoundUpTo(Max(old_mid, new_mid), granularity);
diff --git a/libsanitizer/asan/asan_posix.cpp b/libsanitizer/asan/asan_posix.cpp
index d7f19d84654..63ad735f8bb 100644
--- a/libsanitizer/asan/asan_posix.cpp
+++ b/libsanitizer/asan/asan_posix.cpp
@@ -56,7 +56,7 @@ bool PlatformUnpoisonStacks() {
    if (signal_stack.ss_flags != SS_ONSTACK)
      return false;
  
-  // Since we're on the signal altnerate stack, we cannot find the DEFAULT
+  // Since we're on the signal alternate stack, we cannot find the DEFAULT
    // stack bottom using a local variable.
    uptr default_bottom, tls_addr, tls_size, stack_size;
    GetThreadStackAndTls(/*main=*/false, &default_bottom, &stack_size, &tls_addr,
diff --git a/libsanitizer/asan/asan_rtl.cpp b/libsanitizer/asan/asan_rtl.cpp
index 7b5a929963c..e715d774228 100644
--- a/libsanitizer/asan/asan_rtl.cpp
+++ b/libsanitizer/asan/asan_rtl.cpp
@@ -62,19 +62,9 @@ static void AsanDie() {
    }
  }
  
-static void AsanCheckFailed(const char *file, int line, const char *cond,
-                            u64 v1, u64 v2) {
-  Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
-         line, cond, (uptr)v1, (uptr)v2);
-
-  // Print a stack trace the first time we come here. Otherwise, we probably
-  // failed a CHECK during symbolization.
-  static atomic_uint32_t num_calls;
-  if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) == 0) {
-    PRINT_CURRENT_STACK_CHECK();
-  }
-
-  Die();
+static void CheckUnwind() {
+  GET_STACK_TRACE(kStackTraceMax, common_flags()->fast_unwind_on_check);
+  stack.Print();
  }
  
  // -------------------------- Globals --------------------- {{{1
@@ -432,7 +422,7 @@ static void AsanInitInternal() {
  
    // Install tool-specific callbacks in sanitizer_common.
    AddDieCallback(AsanDie);
-  SetCheckFailedCallback(AsanCheckFailed);
+  SetCheckUnwindCallback(CheckUnwind);
    SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
  
    __sanitizer_set_report_path(common_flags()->log_path);
@@ -568,7 +558,7 @@ void UnpoisonStack(uptr bottom, uptr top, const char *type) {
          type, top, bottom, top - bottom, top - bottom);
      return;
    }
-  PoisonShadow(bottom, top - bottom, 0);
+  PoisonShadow(bottom, RoundUpTo(top - bottom, SHADOW_GRANULARITY), 0);
  }
  
  static void UnpoisonDefaultStack() {
diff --git a/libsanitizer/asan/asan_stack.h b/libsanitizer/asan/asan_stack.h
index 47ca85a1644..b9575d2f427 100644
--- a/libsanitizer/asan/asan_stack.h
+++ b/libsanitizer/asan/asan_stack.h
@@ -54,9 +54,6 @@ u32 GetMallocContextSize();
  #define GET_STACK_TRACE_FATAL_HERE                                \
    GET_STACK_TRACE(kStackTraceMax, common_flags()->fast_unwind_on_fatal)
  
-#define GET_STACK_TRACE_CHECK_HERE                                \
-  GET_STACK_TRACE(kStackTraceMax, common_flags()->fast_unwind_on_check)
-
  #define GET_STACK_TRACE_THREAD                                    \
    GET_STACK_TRACE(kStackTraceMax, true)
  
@@ -71,10 +68,4 @@ u32 GetMallocContextSize();
      stack.Print();              \
    }
  
-#define PRINT_CURRENT_STACK_CHECK() \
-  {                                 \
-    GET_STACK_TRACE_CHECK_HERE;     \
-    stack.Print();                  \
-  }
-
  #endif // ASAN_STACK_H
diff --git a/libsanitizer/asan/asan_thread.cpp b/libsanitizer/asan/asan_thread.cpp
index fb09af0ecca..9c3c86f5735 100644
--- a/libsanitizer/asan/asan_thread.cpp
+++ b/libsanitizer/asan/asan_thread.cpp
@@ -100,18 +100,27 @@ void AsanThread::Destroy() {
    int tid = this->tid();
    VReport(1, "T%d exited\n", tid);
  
-  malloc_storage().CommitBack();
-  if (common_flags()->use_sigaltstack) UnsetAlternateSignalStack();
-  asanThreadRegistry().FinishThread(tid);
-  FlushToDeadThreadStats(&stats_);
-  // We also clear the shadow on thread destruction because
-  // some code may still be executing in later TSD destructors
-  // and we don't want it to have any poisoned stack.
-  ClearShadowForThreadStackAndTLS();
-  DeleteFakeStack(tid);
+  bool was_running =
+      (asanThreadRegistry().FinishThread(tid) == ThreadStatusRunning);
+  if (was_running) {
+    if (AsanThread *thread = GetCurrentThread())
+      CHECK_EQ(this, thread);
+    malloc_storage().CommitBack();
+    if (common_flags()->use_sigaltstack)
+      UnsetAlternateSignalStack();
+    FlushToDeadThreadStats(&stats_);
+    // We also clear the shadow on thread destruction because
+    // some code may still be executing in later TSD destructors
+    // and we don't want it to have any poisoned stack.
+    ClearShadowForThreadStackAndTLS();
+    DeleteFakeStack(tid);
+  } else {
+    CHECK_NE(this, GetCurrentThread());
+  }
    uptr size = RoundUpTo(sizeof(AsanThread), GetPageSizeCached());
    UnmapOrDie(this, size);
-  DTLS_Destroy();
+  if (was_running)
+    DTLS_Destroy();
  }
  
  void AsanThread::StartSwitchFiber(FakeStack **fake_stack_save, uptr bottom,
@@ -219,7 +228,7 @@ FakeStack *AsanThread::AsyncSignalSafeLazyInitFakeStack() {
  }
  
  void AsanThread::Init(const InitOptions *options) {
-  DCHECK_NE(tid(), ThreadRegistry::kUnknownTid);
+  DCHECK_NE(tid(), kInvalidTid);
    next_stack_top_ = next_stack_bottom_ = 0;
    atomic_store(&stack_switching_, false, memory_order_release);
    CHECK_EQ(this->stack_size(), 0U);
@@ -253,12 +262,9 @@ void AsanThread::Init(const InitOptions *options) {
  // SetThreadStackAndTls.
  #if !SANITIZER_FUCHSIA && !SANITIZER_RTEMS
  
-thread_return_t AsanThread::ThreadStart(
-    tid_t os_id, atomic_uintptr_t *signal_thread_is_registered) {
+thread_return_t AsanThread::ThreadStart(tid_t os_id) {
    Init();
    asanThreadRegistry().StartThread(tid(), os_id, ThreadType::Regular, nullptr);
-  if (signal_thread_is_registered)
-    atomic_store(signal_thread_is_registered, 1, memory_order_release);
  
    if (common_flags()->use_sigaltstack) SetAlternateSignalStack();
  
@@ -285,11 +291,10 @@ thread_return_t AsanThread::ThreadStart(
  
  AsanThread *CreateMainThread() {
    AsanThread *main_thread = AsanThread::Create(
-      /* start_routine */ nullptr, /* arg */ nullptr, /* parent_tid */ 0,
+      /* start_routine */ nullptr, /* arg */ nullptr, /* parent_tid */ kMainTid,
        /* stack */ nullptr, /* detached */ true);
    SetCurrentThread(main_thread);
-  main_thread->ThreadStart(internal_getpid(),
-                           /* signal_thread_is_registered */ nullptr);
+  main_thread->ThreadStart(internal_getpid());
    return main_thread;
  }
  
@@ -300,9 +305,9 @@ void AsanThread::SetThreadStackAndTls(const InitOptions *options) {
    DCHECK_EQ(options, nullptr);
    uptr tls_size = 0;
    uptr stack_size = 0;
-  GetThreadStackAndTls(tid() == 0, &stack_bottom_, &stack_size, &tls_begin_,
-                       &tls_size);
-  stack_top_ = stack_bottom_ + stack_size;
+  GetThreadStackAndTls(tid() == kMainTid, &stack_bottom_, &stack_size,
+                       &tls_begin_, &tls_size);
+  stack_top_ = RoundDownTo(stack_bottom_ + stack_size, SHADOW_GRANULARITY);
    tls_end_ = tls_begin_ + tls_size;
    dtls_ = DTLS_Get();
  
@@ -426,7 +431,7 @@ AsanThread *GetCurrentThread() {
        // address. We are not entirely sure that we have correct main thread
        // limits, so only do this magic on Android, and only if the found thread
        // is the main thread.
-      AsanThreadContext *tctx = GetThreadContextByTidLocked(0);
+      AsanThreadContext *tctx = GetThreadContextByTidLocked(kMainTid);
        if (tctx && ThreadStackContainsAddress(tctx, &context)) {
          SetCurrentThread(tctx->thread);
          return tctx->thread;
@@ -463,7 +468,7 @@ AsanThread *FindThreadByStackAddress(uptr addr) {
  void EnsureMainThreadIDIsCorrect() {
    AsanThreadContext *context =
        reinterpret_cast<AsanThreadContext *>(AsanTSDGet());
-  if (context && (context->tid == 0))
+  if (context && (context->tid == kMainTid))
      context->os_id = GetTid();
  }
  
diff --git a/libsanitizer/asan/asan_thread.h b/libsanitizer/asan/asan_thread.h
index ea58de4216a..200069ce0dd 100644
--- a/libsanitizer/asan/asan_thread.h
+++ b/libsanitizer/asan/asan_thread.h
@@ -28,7 +28,6 @@ struct DTLS;
  
  namespace __asan {
  
-const u32 kInvalidTid = 0xffffff;  // Must fit into 24 bits.
  const u32 kMaxNumberOfThreads = (1 << 22);  // 4M
  
  class AsanThread;
@@ -69,8 +68,7 @@ class AsanThread {
    struct InitOptions;
    void Init(const InitOptions *options = nullptr);
  
-  thread_return_t ThreadStart(tid_t os_id,
-                              atomic_uintptr_t *signal_thread_is_registered);
+  thread_return_t ThreadStart(tid_t os_id);
  
    uptr stack_top();
    uptr stack_bottom();
@@ -132,6 +130,8 @@ class AsanThread {
  
    void *extra_spill_area() { return &extra_spill_area_; }
  
+  void *get_arg() { return arg_; }
+
   private:
    // NOTE: There is no AsanThread constructor. It is allocated
    // via mmap() and *must* be valid in zero-initialized state.
diff --git a/libsanitizer/asan/asan_win.cpp b/libsanitizer/asan/asan_win.cpp
index 8044ae16ff9..1577c83cf99 100644
--- a/libsanitizer/asan/asan_win.cpp
+++ b/libsanitizer/asan/asan_win.cpp
@@ -134,7 +134,7 @@ INTERCEPTOR(int, _except_handler4, void *a, void *b, void *c, void *d) {
  static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
    AsanThread *t = (AsanThread *)arg;
    SetCurrentThread(t);
-  return t->ThreadStart(GetTid(), /* signal_thread_is_registered */ nullptr);
+  return t->ThreadStart(GetTid());
  }
  
  INTERCEPTOR_WINAPI(HANDLE, CreateThread, LPSECURITY_ATTRIBUTES security,
diff --git a/libsanitizer/builtins/assembly.h b/libsanitizer/builtins/assembly.h
index f437cb87f60..9c015059af5 100644
--- a/libsanitizer/builtins/assembly.h
+++ b/libsanitizer/builtins/assembly.h
@@ -14,8 +14,8 @@
  #ifndef COMPILERRT_ASSEMBLY_H
  #define COMPILERRT_ASSEMBLY_H
  
-#if defined(__POWERPC__) || defined(__powerpc__) || defined(__ppc__)
-#define SEPARATOR @
+#if defined(__APPLE__) && defined(__aarch64__)
+#define SEPARATOR %%
  #else
  #define SEPARATOR ;
  #endif
@@ -35,14 +35,14 @@
  #define HIDDEN(name) .hidden name
  #define LOCAL_LABEL(name) .L_##name
  #define FILE_LEVEL_DIRECTIVE
-#if defined(__arm__)
+#if defined(__arm__) || defined(__aarch64__)
  #define SYMBOL_IS_FUNC(name) .type name,%function
  #else
  #define SYMBOL_IS_FUNC(name) .type name,@function
  #endif
  #define CONST_SECTION .section .rodata
  
-#if defined(__GNU__) || defined(__FreeBSD__) || defined(__Fuchsia__) || \
+#if defined(__GNU__) || defined(__FreeBSD__) || defined(__Fuchsia__) ||        \
      defined(__linux__)
  #define NO_EXEC_STACK_DIRECTIVE .section .note.GNU-stack,"",%progbits
  #else
@@ -65,6 +65,68 @@
  
  #endif
  
+#if defined(__arm__) || defined(__aarch64__)
+#define FUNC_ALIGN                                                             \
+  .text SEPARATOR                                                              \
+  .balign 16 SEPARATOR
+#else
+#define FUNC_ALIGN
+#endif
+
+// BTI and PAC gnu property note
+#define NT_GNU_PROPERTY_TYPE_0 5
+#define GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000
+#define GNU_PROPERTY_AARCH64_FEATURE_1_BTI 1
+#define GNU_PROPERTY_AARCH64_FEATURE_1_PAC 2
+
+#if defined(__ARM_FEATURE_BTI_DEFAULT)
+#define BTI_FLAG GNU_PROPERTY_AARCH64_FEATURE_1_BTI
+#else
+#define BTI_FLAG 0
+#endif
+
+#if __ARM_FEATURE_PAC_DEFAULT & 3
+#define PAC_FLAG GNU_PROPERTY_AARCH64_FEATURE_1_PAC
+#else
+#define PAC_FLAG 0
+#endif
+
+#define GNU_PROPERTY(type, value)                                              \
+  .pushsection .note.gnu.property, "a" SEPARATOR                               \
+  .p2align 3 SEPARATOR                                                         \
+  .word 4 SEPARATOR                                                            \
+  .word 16 SEPARATOR                                                           \
+  .word NT_GNU_PROPERTY_TYPE_0 SEPARATOR                                       \
+  .asciz "GNU" SEPARATOR                                                       \
+  .word type SEPARATOR                                                         \
+  .word 4 SEPARATOR                                                            \
+  .word value SEPARATOR                                                        \
+  .word 0 SEPARATOR                                                            \
+  .popsection
+
+#if BTI_FLAG != 0
+#define BTI_C hint #34
+#define BTI_J hint #36
+#else
+#define BTI_C
+#define BTI_J
+#endif
+
+#if (BTI_FLAG | PAC_FLAG) != 0
+#define GNU_PROPERTY_BTI_PAC                                                   \
+  GNU_PROPERTY(GNU_PROPERTY_AARCH64_FEATURE_1_AND, BTI_FLAG | PAC_FLAG)
+#else
+#define GNU_PROPERTY_BTI_PAC
+#endif
+
+#if defined(__clang__) || defined(__GCC_HAVE_DWARF2_CFI_ASM)
+#define CFI_START .cfi_startproc
+#define CFI_END .cfi_endproc
+#else
+#define CFI_START
+#define CFI_END
+#endif
+
  #if defined(__arm__)
  
  // Determine actual [ARM][THUMB[1][2]] ISA using compiler predefined macros:
@@ -131,15 +193,24 @@
  #define DEFINE_CODE_STATE
  #endif
  
-#define GLUE2(a, b) a##b
-#define GLUE(a, b) GLUE2(a, b)
+#define GLUE2_(a, b) a##b
+#define GLUE(a, b) GLUE2_(a, b)
+#define GLUE2(a, b) GLUE2_(a, b)
+#define GLUE3_(a, b, c) a##b##c
+#define GLUE3(a, b, c) GLUE3_(a, b, c)
+#define GLUE4_(a, b, c, d) a##b##c##d
+#define GLUE4(a, b, c, d) GLUE4_(a, b, c, d)
+
  #define SYMBOL_NAME(name) GLUE(__USER_LABEL_PREFIX__, name)
  
  #ifdef VISIBILITY_HIDDEN
  #define DECLARE_SYMBOL_VISIBILITY(name)                                        \
    HIDDEN(SYMBOL_NAME(name)) SEPARATOR
+#define DECLARE_SYMBOL_VISIBILITY_UNMANGLED(name) \
+  HIDDEN(name) SEPARATOR
  #else
  #define DECLARE_SYMBOL_VISIBILITY(name)
+#define DECLARE_SYMBOL_VISIBILITY_UNMANGLED(name)
  #endif
  
  #define DEFINE_COMPILERRT_FUNCTION(name)                                       \
@@ -177,6 +248,16 @@
    DECLARE_FUNC_ENCODING                                                        \
    name:
  
+#define DEFINE_COMPILERRT_OUTLINE_FUNCTION_UNMANGLED(name)                     \
+  DEFINE_CODE_STATE                                                            \
+  FUNC_ALIGN                                                                   \
+  .globl name SEPARATOR                                                        \
+  SYMBOL_IS_FUNC(name) SEPARATOR                                               \
+  DECLARE_SYMBOL_VISIBILITY_UNMANGLED(name) SEPARATOR                          \
+  CFI_START SEPARATOR                                                          \
+  DECLARE_FUNC_ENCODING                                                        \
+  name: SEPARATOR BTI_C
+
  #define DEFINE_COMPILERRT_FUNCTION_ALIAS(name, target)                         \
    .globl SYMBOL_NAME(name) SEPARATOR                                           \
    SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR                                  \
@@ -193,8 +274,13 @@
  #ifdef __ELF__
  #define END_COMPILERRT_FUNCTION(name)                                          \
    .size SYMBOL_NAME(name), . - SYMBOL_NAME(name)
+#define END_COMPILERRT_OUTLINE_FUNCTION(name)                                  \
+  CFI_END SEPARATOR                                                            \
+  .size SYMBOL_NAME(name), . - SYMBOL_NAME(name)
  #else
  #define END_COMPILERRT_FUNCTION(name)
+#define END_COMPILERRT_OUTLINE_FUNCTION(name)                                  \
+  CFI_END
  #endif
  
  #endif // COMPILERRT_ASSEMBLY_H
diff --git a/libsanitizer/hwasan/hwasan.cpp b/libsanitizer/hwasan/hwasan.cpp
index c5322110cb6..8d6c25261b8 100644
--- a/libsanitizer/hwasan/hwasan.cpp
+++ b/libsanitizer/hwasan/hwasan.cpp
@@ -128,16 +128,11 @@ static void InitializeFlags() {
    if (common_flags()->help) parser.PrintFlagDescriptions();
  }
  
-static void HWAsanCheckFailed(const char *file, int line, const char *cond,
-                              u64 v1, u64 v2) {
-  Report("HWAddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
-         line, cond, (uptr)v1, (uptr)v2);
-  PRINT_CURRENT_STACK_CHECK();
-  Die();
+static void CheckUnwind() {
+  GET_FATAL_STACK_TRACE_PC_BP(StackTrace::GetCurrentPc(), GET_CURRENT_FRAME());
+  stack.Print();
  }
  
-static constexpr uptr kMemoryUsageBufferSize = 4096;
-
  static void HwasanFormatMemoryUsage(InternalScopedString &s) {
    HwasanThreadList &thread_list = hwasanThreadList();
    auto thread_stats = thread_list.GetThreadStats();
@@ -155,6 +150,8 @@ static void HwasanFormatMemoryUsage(InternalScopedString &s) {
  }
  
  #if SANITIZER_ANDROID
+static constexpr uptr kMemoryUsageBufferSize = 4096;
+
  static char *memory_usage_buffer = nullptr;
  
  static void InitMemoryUsage() {
@@ -171,7 +168,7 @@ void UpdateMemoryUsage() {
      return;
    if (!memory_usage_buffer)
      InitMemoryUsage();
-  InternalScopedString s(kMemoryUsageBufferSize);
+  InternalScopedString s;
    HwasanFormatMemoryUsage(s);
    internal_strncpy(memory_usage_buffer, s.data(), kMemoryUsageBufferSize - 1);
    memory_usage_buffer[kMemoryUsageBufferSize - 1] = '\0';
@@ -271,7 +268,7 @@ void __hwasan_init() {
    InitializeFlags();
  
    // Install tool-specific callbacks in sanitizer_common.
-  SetCheckFailedCallback(HWAsanCheckFailed);
+  SetCheckUnwindCallback(CheckUnwind);
  
    __sanitizer_set_report_path(common_flags()->log_path);
  
@@ -493,7 +490,7 @@ extern "C" void *__hwasan_extra_spill_area() {
  }
  
  void __hwasan_print_memory_usage() {
-  InternalScopedString s(kMemoryUsageBufferSize);
+  InternalScopedString s;
    HwasanFormatMemoryUsage(s);
    Printf("%s\n", s.data());
  }
diff --git a/libsanitizer/hwasan/hwasan.h b/libsanitizer/hwasan/hwasan.h
index d4521efd089..8515df559f3 100644
--- a/libsanitizer/hwasan/hwasan.h
+++ b/libsanitizer/hwasan/hwasan.h
@@ -14,11 +14,12 @@
  #ifndef HWASAN_H
  #define HWASAN_H
  
+#include "hwasan_flags.h"
+#include "hwasan_interface_internal.h"
+#include "sanitizer_common/sanitizer_common.h"
  #include "sanitizer_common/sanitizer_flags.h"
  #include "sanitizer_common/sanitizer_internal_defs.h"
  #include "sanitizer_common/sanitizer_stacktrace.h"
-#include "hwasan_interface_internal.h"
-#include "hwasan_flags.h"
  #include "ubsan/ubsan_platform.h"
  
  #ifndef HWASAN_CONTAINS_UBSAN
@@ -35,10 +36,31 @@
  
  typedef u8 tag_t;
  
+#if defined(__x86_64__)
+// Tags are done in middle bits using userspace aliasing.
+constexpr unsigned kAddressTagShift = 39;
+constexpr unsigned kTagBits = 3;
+
+// The alias region is placed next to the shadow so the upper bits of all
+// taggable addresses matches the upper bits of the shadow base.  This shift
+// value determines which upper bits must match.  It has a floor of 44 since the
+// shadow is always 8TB.
+// TODO(morehouse): In alias mode we can shrink the shadow and use a
+// simpler/faster shadow calculation.
+constexpr unsigned kTaggableRegionCheckShift =
+    __sanitizer::Max(kAddressTagShift + kTagBits + 1U, 44U);
+#else
  // TBI (Top Byte Ignore) feature of AArch64: bits [63:56] are ignored in address
  // translation and can be used to store a tag.
-const unsigned kAddressTagShift = 56;
-const uptr kAddressTagMask = 0xFFUL << kAddressTagShift;
+constexpr unsigned kAddressTagShift = 56;
+constexpr unsigned kTagBits = 8;
+#endif  // defined(__x86_64__)
+
+// Mask for extracting tag bits from the lower 8 bits.
+constexpr uptr kTagMask = (1UL << kTagBits) - 1;
+
+// Mask for extracting tag bits from full pointers.
+constexpr uptr kAddressTagMask = kTagMask << kAddressTagShift;
  
  // Minimal alignment of the shadow base address. Determines the space available
  // for threads and stack histories. This is an ABI constant.
@@ -50,7 +72,7 @@ const unsigned kRecordFPLShift = 4;
  const unsigned kRecordFPModulus = 1 << (64 - kRecordFPShift + kRecordFPLShift);
  
  static inline tag_t GetTagFromPointer(uptr p) {
-  return p >> kAddressTagShift;
+  return (p >> kAddressTagShift) & kTagMask;
  }
  
  static inline uptr UntagAddr(uptr tagged_addr) {
@@ -105,15 +127,6 @@ void InstallAtExitHandler();
    if (hwasan_inited)                                     \
      stack.Unwind(pc, bp, nullptr, common_flags()->fast_unwind_on_fatal)
  
-#define GET_FATAL_STACK_TRACE_HERE \
-  GET_FATAL_STACK_TRACE_PC_BP(StackTrace::GetCurrentPc(), GET_CURRENT_FRAME())
-
-#define PRINT_CURRENT_STACK_CHECK() \
-  {                                 \
-    GET_FATAL_STACK_TRACE_HERE;     \
-    stack.Print();                  \
-  }
-
  void HwasanTSDInit();
  void HwasanTSDThreadInit();
  
diff --git a/libsanitizer/hwasan/hwasan_allocator.cpp b/libsanitizer/hwasan/hwasan_allocator.cpp
index 0b6b7347892..a6fc794082a 100644
--- a/libsanitizer/hwasan/hwasan_allocator.cpp
+++ b/libsanitizer/hwasan/hwasan_allocator.cpp
@@ -29,8 +29,8 @@ static AllocatorCache fallback_allocator_cache;
  static SpinMutex fallback_mutex;
  static atomic_uint8_t hwasan_allocator_tagging_enabled;
  
-static const tag_t kFallbackAllocTag = 0xBB;
-static const tag_t kFallbackFreeTag = 0xBC;
+static constexpr tag_t kFallbackAllocTag = 0xBB & kTagMask;
+static constexpr tag_t kFallbackFreeTag = 0xBC;
  
  enum RightAlignMode {
    kRightAlignNever,
@@ -84,7 +84,8 @@ void HwasanAllocatorInit() {
    atomic_store_relaxed(&hwasan_allocator_tagging_enabled,
                         !flags()->disable_allocator_tagging);
    SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
-  allocator.Init(common_flags()->allocator_release_to_os_interval_ms);
+  allocator.Init(common_flags()->allocator_release_to_os_interval_ms,
+                 kAliasRegionStart);
    for (uptr i = 0; i < sizeof(tail_magic); i++)
      tail_magic[i] = GetCurrentThread()->GenerateRandomTag();
  }
@@ -148,7 +149,8 @@ static void *HwasanAllocate(StackTrace *stack, uptr orig_size, uptr alignment,
    // Tagging can only be skipped when both tag_in_malloc and tag_in_free are
    // false. When tag_in_malloc = false and tag_in_free = true malloc needs to
    // retag to 0.
-  if ((flags()->tag_in_malloc || flags()->tag_in_free) &&
+  if (InTaggableRegion(reinterpret_cast<uptr>(user_ptr)) &&
+      (flags()->tag_in_malloc || flags()->tag_in_free) &&
        atomic_load_relaxed(&hwasan_allocator_tagging_enabled)) {
      if (flags()->tag_in_malloc && malloc_bisect(stack, orig_size)) {
        tag_t tag = t ? t->GenerateRandomTag() : kFallbackAllocTag;
@@ -175,6 +177,8 @@ static void *HwasanAllocate(StackTrace *stack, uptr orig_size, uptr alignment,
  static bool PointerAndMemoryTagsMatch(void *tagged_ptr) {
    CHECK(tagged_ptr);
    uptr tagged_uptr = reinterpret_cast<uptr>(tagged_ptr);
+  if (!InTaggableRegion(tagged_uptr))
+    return true;
    tag_t mem_tag = *reinterpret_cast<tag_t *>(
        MemToShadow(reinterpret_cast<uptr>(UntagPtr(tagged_ptr))));
    return PossiblyShortTagMatches(mem_tag, tagged_uptr, 1);
@@ -187,7 +191,9 @@ static void HwasanDeallocate(StackTrace *stack, void *tagged_ptr) {
    if (!PointerAndMemoryTagsMatch(tagged_ptr))
      ReportInvalidFree(stack, reinterpret_cast<uptr>(tagged_ptr));
  
-  void *untagged_ptr = UntagPtr(tagged_ptr);
+  void *untagged_ptr = InTaggableRegion(reinterpret_cast<uptr>(tagged_ptr))
+                           ? UntagPtr(tagged_ptr)
+                           : tagged_ptr;
    void *aligned_ptr = reinterpret_cast<void *>(
        RoundDownTo(reinterpret_cast<uptr>(untagged_ptr), kShadowAlignment));
    Metadata *meta =
@@ -219,10 +225,14 @@ static void HwasanDeallocate(StackTrace *stack, void *tagged_ptr) {
          Min(TaggedSize(orig_size), (uptr)flags()->max_free_fill_size);
      internal_memset(aligned_ptr, flags()->free_fill_byte, fill_size);
    }
-  if (flags()->tag_in_free && malloc_bisect(stack, 0) &&
-      atomic_load_relaxed(&hwasan_allocator_tagging_enabled))
+  if (InTaggableRegion(reinterpret_cast<uptr>(tagged_ptr)) &&
+      flags()->tag_in_free && malloc_bisect(stack, 0) &&
+      atomic_load_relaxed(&hwasan_allocator_tagging_enabled)) {
+    // Always store full 8-bit tags on free to maximize UAF detection.
+    tag_t tag = t ? t->GenerateRandomTag(/*num_bits=*/8) : kFallbackFreeTag;
      TagMemoryAligned(reinterpret_cast<uptr>(aligned_ptr), TaggedSize(orig_size),
-                     t ? t->GenerateRandomTag() : kFallbackFreeTag);
+                     tag);
+  }
    if (t) {
      allocator.Deallocate(t->allocator_cache(), aligned_ptr);
      if (auto *ha = t->heap_allocations())
@@ -365,7 +375,7 @@ int hwasan_posix_memalign(void **memptr, uptr alignment, uptr size,
      // OOM error is already taken care of by HwasanAllocate.
      return errno_ENOMEM;
    CHECK(IsAligned((uptr)ptr, alignment));
-  *(void **)UntagPtr(memptr) = ptr;
+  *memptr = ptr;
    return 0;
  }
  
diff --git a/libsanitizer/hwasan/hwasan_allocator.h b/libsanitizer/hwasan/hwasan_allocator.h
index 43670a6a3fb..03bbcff3f0f 100644
--- a/libsanitizer/hwasan/hwasan_allocator.h
+++ b/libsanitizer/hwasan/hwasan_allocator.h
@@ -13,13 +13,15 @@
  #ifndef HWASAN_ALLOCATOR_H
  #define HWASAN_ALLOCATOR_H
  
+#include "hwasan.h"
+#include "hwasan_interface_internal.h"
+#include "hwasan_poisoning.h"
  #include "sanitizer_common/sanitizer_allocator.h"
  #include "sanitizer_common/sanitizer_allocator_checks.h"
  #include "sanitizer_common/sanitizer_allocator_interface.h"
  #include "sanitizer_common/sanitizer_allocator_report.h"
  #include "sanitizer_common/sanitizer_common.h"
  #include "sanitizer_common/sanitizer_ring_buffer.h"
-#include "hwasan_poisoning.h"
  
  #if !defined(__aarch64__) && !defined(__x86_64__)
  #error Unsupported platform
@@ -55,7 +57,12 @@ static const uptr kMaxAllowedMallocSize = 1UL << 40;  // 1T
  
  struct AP64 {
    static const uptr kSpaceBeg = ~0ULL;
+
+#if defined(__x86_64__)
+  static const uptr kSpaceSize = 1ULL << kAddressTagShift;
+#else
    static const uptr kSpaceSize = 0x2000000000ULL;
+#endif
    static const uptr kMetadataSize = sizeof(Metadata);
    typedef __sanitizer::VeryDenseSizeClassMap SizeClassMap;
    using AddressSpaceView = LocalAddressSpaceView;
@@ -102,6 +109,16 @@ typedef RingBuffer<HeapAllocationRecord> HeapAllocationsRingBuffer;
  
  void GetAllocatorStats(AllocatorStatCounters s);
  
+inline bool InTaggableRegion(uptr addr) {
+#if defined(__x86_64__)
+  // Aliases are mapped next to shadow so that the upper bits match the shadow
+  // base.
+  return (addr >> kTaggableRegionCheckShift) ==
+         (__hwasan_shadow_memory_dynamic_address >> kTaggableRegionCheckShift);
+#endif
+  return true;
+}
+
  } // namespace __hwasan
  
  #endif // HWASAN_ALLOCATOR_H
diff --git a/libsanitizer/hwasan/hwasan_checks.h b/libsanitizer/hwasan/hwasan_checks.h
index a8de0fef20f..ab543ea88be 100644
--- a/libsanitizer/hwasan/hwasan_checks.h
+++ b/libsanitizer/hwasan/hwasan_checks.h
@@ -13,6 +13,7 @@
  #ifndef HWASAN_CHECKS_H
  #define HWASAN_CHECKS_H
  
+#include "hwasan_allocator.h"
  #include "hwasan_mapping.h"
  #include "sanitizer_common/sanitizer_common.h"
  
@@ -81,6 +82,8 @@ enum class AccessType { Load, Store };
  
  template <ErrorAction EA, AccessType AT, unsigned LogSize>
  __attribute__((always_inline, nodebug)) static void CheckAddress(uptr p) {
+  if (!InTaggableRegion(p))
+    return;
    uptr ptr_raw = p & ~kAddressTagMask;
    tag_t mem_tag = *(tag_t *)MemToShadow(ptr_raw);
    if (UNLIKELY(!PossiblyShortTagMatches(mem_tag, p, 1 << LogSize))) {
@@ -94,7 +97,7 @@ __attribute__((always_inline, nodebug)) static void CheckAddress(uptr p) {
  template <ErrorAction EA, AccessType AT>
  __attribute__((always_inline, nodebug)) static void CheckAddressSized(uptr p,
                                                                        uptr sz) {
-  if (sz == 0)
+  if (sz == 0 || !InTaggableRegion(p))
      return;
    tag_t ptr_tag = GetTagFromPointer(p);
    uptr ptr_raw = p & ~kAddressTagMask;
diff --git a/libsanitizer/hwasan/hwasan_dynamic_shadow.cpp b/libsanitizer/hwasan/hwasan_dynamic_shadow.cpp
index 12730b29bae..f53276e330d 100644
--- a/libsanitizer/hwasan/hwasan_dynamic_shadow.cpp
+++ b/libsanitizer/hwasan/hwasan_dynamic_shadow.cpp
@@ -12,15 +12,17 @@
  ///
  //===----------------------------------------------------------------------===//
  
-#include "hwasan.h"
  #include "hwasan_dynamic_shadow.h"
-#include "hwasan_mapping.h"
-#include "sanitizer_common/sanitizer_common.h"
-#include "sanitizer_common/sanitizer_posix.h"
  
  #include <elf.h>
  #include <link.h>
  
+#include "hwasan.h"
+#include "hwasan_mapping.h"
+#include "hwasan_thread_list.h"
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_posix.h"
+
  // The code in this file needs to run in an unrelocated binary. It should not
  // access any external symbol, including its own non-hidden globals.
  
@@ -117,6 +119,12 @@ namespace __hwasan {
  void InitShadowGOT() {}
  
  uptr FindDynamicShadowStart(uptr shadow_size_bytes) {
+#if defined(__x86_64__)
+  constexpr uptr kAliasSize = 1ULL << kAddressTagShift;
+  constexpr uptr kNumAliases = 1ULL << kTagBits;
+  return MapDynamicShadowAndAliases(shadow_size_bytes, kAliasSize, kNumAliases,
+                                    RingBufferSize());
+#endif
    return MapDynamicShadow(shadow_size_bytes, kShadowScale, kShadowBaseAlignment,
                            kHighMemEnd);
  }
diff --git a/libsanitizer/hwasan/hwasan_flags.h b/libsanitizer/hwasan/hwasan_flags.h
index 0a6998f675d..b17750158d0 100644
--- a/libsanitizer/hwasan/hwasan_flags.h
+++ b/libsanitizer/hwasan/hwasan_flags.h
@@ -12,6 +12,8 @@
  #ifndef HWASAN_FLAGS_H
  #define HWASAN_FLAGS_H
  
+#include "sanitizer_common/sanitizer_internal_defs.h"
+
  namespace __hwasan {
  
  struct Flags {
diff --git a/libsanitizer/hwasan/hwasan_flags.inc b/libsanitizer/hwasan/hwasan_flags.inc
index 8e431d9c4ff..18ea47f981b 100644
--- a/libsanitizer/hwasan/hwasan_flags.inc
+++ b/libsanitizer/hwasan/hwasan_flags.inc
@@ -72,3 +72,12 @@ HWASAN_FLAG(uptr, malloc_bisect_right, 0,
  HWASAN_FLAG(bool, malloc_bisect_dump, false,
              "Print all allocations within [malloc_bisect_left, "
              "malloc_bisect_right] range ")
+
+
+// Exit if we fail to enable the AArch64 kernel ABI relaxation which allows
+// tagged pointers in syscalls.  This is the default, but being able to disable
+// that behaviour is useful for running the testsuite on more platforms (the
+// testsuite can run since we manually ensure any pointer arguments to syscalls
+// are untagged before the call.
+HWASAN_FLAG(bool, fail_without_syscall_abi, true,
+            "Exit if fail to request relaxed syscall ABI.")
diff --git a/libsanitizer/hwasan/hwasan_interceptors.cpp b/libsanitizer/hwasan/hwasan_interceptors.cpp
index 44e569ee6d7..ad67e2787d3 100644
--- a/libsanitizer/hwasan/hwasan_interceptors.cpp
+++ b/libsanitizer/hwasan/hwasan_interceptors.cpp
@@ -221,8 +221,7 @@ INTERCEPTOR(int, pthread_create, void *th, void *attr, void *(*callback)(void*),
    ThreadStartArg *A = reinterpret_cast<ThreadStartArg *> (MmapOrDie(
        GetPageSizeCached(), "pthread_create"));
    *A = {callback, param};
-  int res = REAL(pthread_create)(UntagPtr(th), UntagPtr(attr),
-                                 &HwasanThreadStartFunc, A);
+  int res = REAL(pthread_create)(th, attr, &HwasanThreadStartFunc, A);
    return res;
  }
  
diff --git a/libsanitizer/hwasan/hwasan_interceptors_vfork.S b/libsanitizer/hwasan/hwasan_interceptors_vfork.S
index 23d565936d8..fd20825e3da 100644
--- a/libsanitizer/hwasan/hwasan_interceptors_vfork.S
+++ b/libsanitizer/hwasan/hwasan_interceptors_vfork.S
@@ -1,4 +1,5 @@
  #include "sanitizer_common/sanitizer_asm.h"
+#include "builtins/assembly.h"
  
  #if defined(__linux__) && HWASAN_WITH_INTERCEPTORS
  #define COMMON_INTERCEPTOR_SPILL_AREA __hwasan_extra_spill_area
@@ -9,3 +10,5 @@
  #endif
  
  NO_EXEC_STACK_DIRECTIVE
+
+GNU_PROPERTY_BTI_PAC
diff --git a/libsanitizer/hwasan/hwasan_interface_internal.h b/libsanitizer/hwasan/hwasan_interface_internal.h
index aedda317497..25c0f94fe51 100644
--- a/libsanitizer/hwasan/hwasan_interface_internal.h
+++ b/libsanitizer/hwasan/hwasan_interface_internal.h
@@ -222,6 +222,9 @@ SANITIZER_INTERFACE_ATTRIBUTE
  void *__hwasan_memset(void *s, int c, uptr n);
  SANITIZER_INTERFACE_ATTRIBUTE
  void *__hwasan_memmove(void *dest, const void *src, uptr n);
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __hwasan_set_error_report_callback(void (*callback)(const char *));
  }  // extern "C"
  
  #endif  // HWASAN_INTERFACE_INTERNAL_H
diff --git a/libsanitizer/hwasan/hwasan_linux.cpp b/libsanitizer/hwasan/hwasan_linux.cpp
index e99926d355c..8ce0ff7da95 100644
--- a/libsanitizer/hwasan/hwasan_linux.cpp
+++ b/libsanitizer/hwasan/hwasan_linux.cpp
@@ -76,6 +76,8 @@ uptr kHighShadowEnd;
  uptr kHighMemStart;
  uptr kHighMemEnd;
  
+uptr kAliasRegionStart;  // Always 0 on non-x86.
+
  static void PrintRange(uptr start, uptr end, const char *name) {
    Printf("|| [%p, %p] || %.*s ||\n", (void *)start, (void *)end, 10, name);
  }
@@ -119,9 +121,11 @@ void InitPrctl() {
  #define PR_GET_TAGGED_ADDR_CTRL 56
  #define PR_TAGGED_ADDR_ENABLE (1UL << 0)
    // Check we're running on a kernel that can use the tagged address ABI.
-  if (internal_prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0) == (uptr)-1 &&
-      errno == EINVAL) {
-#if SANITIZER_ANDROID
+  int local_errno = 0;
+  if (internal_iserror(internal_prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0),
+                       &local_errno) &&
+      local_errno == EINVAL) {
+#if SANITIZER_ANDROID || defined(__x86_64__)
      // Some older Android kernels have the tagged pointer ABI on
      // unconditionally, and hence don't have the tagged-addr prctl while still
      // allow the ABI.
@@ -129,17 +133,20 @@ void InitPrctl() {
      // case.
      return;
  #else
-    Printf(
-        "FATAL: "
-        "HWAddressSanitizer requires a kernel with tagged address ABI.\n");
-    Die();
+    if (flags()->fail_without_syscall_abi) {
+      Printf(
+          "FATAL: "
+          "HWAddressSanitizer requires a kernel with tagged address ABI.\n");
+      Die();
+    }
  #endif
    }
  
    // Turn on the tagged address ABI.
-  if (internal_prctl(PR_SET_TAGGED_ADDR_CTRL, PR_TAGGED_ADDR_ENABLE, 0, 0, 0) ==
-          (uptr)-1 ||
-      !internal_prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0)) {
+  if ((internal_iserror(internal_prctl(PR_SET_TAGGED_ADDR_CTRL,
+                                       PR_TAGGED_ADDR_ENABLE, 0, 0, 0)) ||
+       !internal_prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0)) &&
+      flags()->fail_without_syscall_abi) {
      Printf(
          "FATAL: HWAddressSanitizer failed to enable tagged address syscall "
          "ABI.\nSuggest check `sysctl abi.tagged_addr_disabled` "
@@ -174,6 +181,18 @@ bool InitShadow() {
    // High memory starts where allocated shadow allows.
    kHighMemStart = ShadowToMem(kHighShadowStart);
  
+#if defined(__x86_64__)
+  constexpr uptr kAliasRegionOffset = 1ULL << (kTaggableRegionCheckShift - 1);
+  kAliasRegionStart =
+      __hwasan_shadow_memory_dynamic_address + kAliasRegionOffset;
+
+  CHECK_EQ(kAliasRegionStart >> kTaggableRegionCheckShift,
+           __hwasan_shadow_memory_dynamic_address >> kTaggableRegionCheckShift);
+  CHECK_EQ(
+      (kAliasRegionStart + kAliasRegionOffset - 1) >> kTaggableRegionCheckShift,
+      __hwasan_shadow_memory_dynamic_address >> kTaggableRegionCheckShift);
+#endif
+
    // Check the sanity of the defined memory ranges (there might be gaps).
    CHECK_EQ(kHighMemStart % GetMmapGranularity(), 0);
    CHECK_GT(kHighMemStart, kHighShadowEnd);
@@ -217,7 +236,9 @@ void InitThreads() {
  }
  
  bool MemIsApp(uptr p) {
+#if !defined(__x86_64__)  // Memory outside the alias range has non-zero tags.
    CHECK(GetTagFromPointer(p) == 0);
+#endif
    return p >= kHighMemStart || (p >= kLowMemStart && p <= kLowMemEnd);
  }
  
diff --git a/libsanitizer/hwasan/hwasan_mapping.h b/libsanitizer/hwasan/hwasan_mapping.h
index c149687bdfa..8243d1ec7ed 100644
--- a/libsanitizer/hwasan/hwasan_mapping.h
+++ b/libsanitizer/hwasan/hwasan_mapping.h
@@ -48,6 +48,8 @@ extern uptr kHighShadowEnd;
  extern uptr kHighMemStart;
  extern uptr kHighMemEnd;
  
+extern uptr kAliasRegionStart;
+
  inline uptr MemToShadow(uptr untagged_addr) {
    return (untagged_addr >> kShadowScale) +
           __hwasan_shadow_memory_dynamic_address;
diff --git a/libsanitizer/hwasan/hwasan_memintrinsics.cpp b/libsanitizer/hwasan/hwasan_memintrinsics.cpp
index e82d77a1bc1..fab017aae60 100644
--- a/libsanitizer/hwasan/hwasan_memintrinsics.cpp
+++ b/libsanitizer/hwasan/hwasan_memintrinsics.cpp
@@ -24,7 +24,7 @@ using namespace __hwasan;
  void *__hwasan_memset(void *block, int c, uptr size) {
    CheckAddressSized<ErrorAction::Recover, AccessType::Store>(
        reinterpret_cast<uptr>(block), size);
-  return memset(UntagPtr(block), c, size);
+  return memset(block, c, size);
  }
  
  void *__hwasan_memcpy(void *to, const void *from, uptr size) {
@@ -32,7 +32,7 @@ void *__hwasan_memcpy(void *to, const void *from, uptr size) {
        reinterpret_cast<uptr>(to), size);
    CheckAddressSized<ErrorAction::Recover, AccessType::Load>(
        reinterpret_cast<uptr>(from), size);
-  return memcpy(UntagPtr(to), UntagPtr(from), size);
+  return memcpy(to, from, size);
  }
  
  void *__hwasan_memmove(void *to, const void *from, uptr size) {
diff --git a/libsanitizer/hwasan/hwasan_new_delete.cpp b/libsanitizer/hwasan/hwasan_new_delete.cpp
index 8d01d3944f2..69cddda736e 100644
--- a/libsanitizer/hwasan/hwasan_new_delete.cpp
+++ b/libsanitizer/hwasan/hwasan_new_delete.cpp
@@ -27,6 +27,12 @@
    void *res = hwasan_malloc(size, &stack);\
    if (!nothrow && UNLIKELY(!res)) ReportOutOfMemory(size, &stack);\
    return res
+#define OPERATOR_NEW_ALIGN_BODY(nothrow)                                    \
+  GET_MALLOC_STACK_TRACE;                                                   \
+  void *res = hwasan_aligned_alloc(static_cast<uptr>(align), size, &stack); \
+  if (!nothrow && UNLIKELY(!res))                                           \
+    ReportOutOfMemory(size, &stack);                                        \
+  return res
  
  #define OPERATOR_DELETE_BODY \
    GET_MALLOC_STACK_TRACE; \
@@ -50,6 +56,7 @@ using namespace __hwasan;
  // Fake std::nothrow_t to avoid including <new>.
  namespace std {
    struct nothrow_t {};
+  enum class align_val_t : size_t {};
  }  // namespace std
  
  
@@ -66,6 +73,22 @@ INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
  void *operator new[](size_t size, std::nothrow_t const&) {
    OPERATOR_NEW_BODY(true /*nothrow*/);
  }
+INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void *operator new(
+    size_t size, std::align_val_t align) {
+  OPERATOR_NEW_ALIGN_BODY(false /*nothrow*/);
+}
+INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void *operator new[](
+    size_t size, std::align_val_t align) {
+  OPERATOR_NEW_ALIGN_BODY(false /*nothrow*/);
+}
+INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void *operator new(
+    size_t size, std::align_val_t align, std::nothrow_t const &) {
+  OPERATOR_NEW_ALIGN_BODY(true /*nothrow*/);
+}
+INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void *operator new[](
+    size_t size, std::align_val_t align, std::nothrow_t const &) {
+  OPERATOR_NEW_ALIGN_BODY(true /*nothrow*/);
+}
  
  INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
  void operator delete(void *ptr) NOEXCEPT { OPERATOR_DELETE_BODY; }
@@ -77,5 +100,21 @@ INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
  void operator delete[](void *ptr, std::nothrow_t const&) {
    OPERATOR_DELETE_BODY;
  }
+INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void operator delete(
+    void *ptr, std::align_val_t align) NOEXCEPT {
+  OPERATOR_DELETE_BODY;
+}
+INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void operator delete[](
+    void *ptr, std::align_val_t) NOEXCEPT {
+  OPERATOR_DELETE_BODY;
+}
+INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void operator delete(
+    void *ptr, std::align_val_t, std::nothrow_t const &) NOEXCEPT {
+  OPERATOR_DELETE_BODY;
+}
+INTERCEPTOR_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void operator delete[](
+    void *ptr, std::align_val_t, std::nothrow_t const &) NOEXCEPT {
+  OPERATOR_DELETE_BODY;
+}
  
  #endif // OPERATOR_NEW_BODY
diff --git a/libsanitizer/hwasan/hwasan_report.cpp b/libsanitizer/hwasan/hwasan_report.cpp
index 894a149775f..c0217799391 100644
--- a/libsanitizer/hwasan/hwasan_report.cpp
+++ b/libsanitizer/hwasan/hwasan_report.cpp
@@ -43,12 +43,16 @@ class ScopedReport {
    }
  
    ~ScopedReport() {
+    void (*report_cb)(const char *);
      {
        BlockingMutexLock lock(&error_message_lock_);
-      if (fatal)
-        SetAbortMessage(error_message_.data());
+      report_cb = error_report_callback_;
        error_message_ptr_ = nullptr;
      }
+    if (report_cb)
+      report_cb(error_message_.data());
+    if (fatal)
+      SetAbortMessage(error_message_.data());
      if (common_flags()->print_module_map >= 2 ||
          (fatal && common_flags()->print_module_map))
        DumpProcessMap();
@@ -66,6 +70,12 @@ class ScopedReport {
      // overwrite old trailing '\0', keep new trailing '\0' untouched.
      internal_memcpy(&(*error_message_ptr_)[old_size - 1], msg, len);
    }
+
+  static void SetErrorReportCallback(void (*callback)(const char *)) {
+    BlockingMutexLock lock(&error_message_lock_);
+    error_report_callback_ = callback;
+  }
+
   private:
    ScopedErrorReportLock error_report_lock_;
    InternalMmapVector<char> error_message_;
@@ -73,10 +83,12 @@ class ScopedReport {
  
    static InternalMmapVector<char> *error_message_ptr_;
    static BlockingMutex error_message_lock_;
+  static void (*error_report_callback_)(const char *);
  };
  
  InternalMmapVector<char> *ScopedReport::error_message_ptr_;
  BlockingMutex ScopedReport::error_message_lock_;
+void (*ScopedReport::error_report_callback_)(const char *);
  
  // If there is an active ScopedReport, append to its error message.
  void AppendToErrorMessageBuffer(const char *buffer) {
@@ -212,7 +224,7 @@ static void PrintStackAllocations(StackAllocationsRingBuffer *sa,
  
    // We didn't find any locals. Most likely we don't have symbols, so dump
    // the information that we have for offline analysis.
-  InternalScopedString frame_desc(GetPageSizeCached() * 2);
+  InternalScopedString frame_desc;
    Printf("Previously allocated frames:\n");
    for (uptr i = 0; i < frames; i++) {
      const uptr *record_addr = &(*sa)[i];
@@ -447,7 +459,7 @@ static void PrintTagInfoAroundAddr(tag_t *tag_ptr, uptr num_rows,
        RoundDownTo(reinterpret_cast<uptr>(tag_ptr), row_len));
    tag_t *beg_row = center_row_beg - row_len * (num_rows / 2);
    tag_t *end_row = center_row_beg + row_len * ((num_rows + 1) / 2);
-  InternalScopedString s(GetPageSizeCached() * 8);
+  InternalScopedString s;
    for (tag_t *row = beg_row; row < end_row; row += row_len) {
      s.append("%s", row == center_row_beg ? "=>" : "  ");
      s.append("%p:", row);
@@ -535,7 +547,7 @@ void ReportTailOverwritten(StackTrace *stack, uptr tagged_addr, uptr orig_size,
      GetStackTraceFromId(chunk.GetAllocStackId()).Print();
    }
  
-  InternalScopedString s(GetPageSizeCached() * 8);
+  InternalScopedString s;
    CHECK_GT(tail_size, 0U);
    CHECK_LT(tail_size, kShadowAlignment);
    u8 *tail = reinterpret_cast<u8*>(untagged_addr + orig_size);
@@ -650,3 +662,7 @@ void ReportRegisters(uptr *frame, uptr pc) {
  }
  
  }  // namespace __hwasan
+
+void __hwasan_set_error_report_callback(void (*callback)(const char *)) {
+  __hwasan::ScopedReport::SetErrorReportCallback(callback);
+}
diff --git a/libsanitizer/hwasan/hwasan_setjmp.S b/libsanitizer/hwasan/hwasan_setjmp.S
index 0c135433194..381af63363c 100644
--- a/libsanitizer/hwasan/hwasan_setjmp.S
+++ b/libsanitizer/hwasan/hwasan_setjmp.S
@@ -12,6 +12,7 @@
  //===----------------------------------------------------------------------===//
  
  #include "sanitizer_common/sanitizer_asm.h"
+#include "builtins/assembly.h"
  
  #if HWASAN_WITH_INTERCEPTORS && defined(__aarch64__)
  #include "sanitizer_common/sanitizer_platform.h"
@@ -34,6 +35,7 @@
  ASM_TYPE_FUNCTION(__interceptor_setjmp)
  __interceptor_setjmp:
    CFI_STARTPROC
+  BTI_C
    mov	x1, #0
    b	__interceptor_sigsetjmp
    CFI_ENDPROC
@@ -46,6 +48,7 @@ ASM_SIZE(__interceptor_setjmp)
  ASM_TYPE_FUNCTION(__interceptor_setjmp_bionic)
  __interceptor_setjmp_bionic:
    CFI_STARTPROC
+  BTI_C
    mov	x1, #1
    b	__interceptor_sigsetjmp
    CFI_ENDPROC
@@ -56,6 +59,7 @@ ASM_SIZE(__interceptor_setjmp_bionic)
  ASM_TYPE_FUNCTION(__interceptor_sigsetjmp)
  __interceptor_sigsetjmp:
    CFI_STARTPROC
+  BTI_C
    stp	x19, x20, [x0, #0<<3]
    stp	x21, x22, [x0, #2<<3]
    stp	x23, x24, [x0, #4<<3]
@@ -98,3 +102,5 @@ ALIAS __interceptor_setjmp, _setjmp
  
  // We do not need executable stack.
  NO_EXEC_STACK_DIRECTIVE
+
+GNU_PROPERTY_BTI_PAC
diff --git a/libsanitizer/hwasan/hwasan_tag_mismatch_aarch64.S b/libsanitizer/hwasan/hwasan_tag_mismatch_aarch64.S
index 08df12736bb..bcb0df42019 100644
--- a/libsanitizer/hwasan/hwasan_tag_mismatch_aarch64.S
+++ b/libsanitizer/hwasan/hwasan_tag_mismatch_aarch64.S
@@ -1,4 +1,5 @@
  #include "sanitizer_common/sanitizer_asm.h"
+#include "builtins/assembly.h"
  
  // The content of this file is AArch64-only:
  #if defined(__aarch64__)
@@ -74,6 +75,8 @@
  .global __hwasan_tag_mismatch
  .type __hwasan_tag_mismatch, %function
  __hwasan_tag_mismatch:
+  BTI_J
+
    // Compute the granule position one past the end of the access.
    mov x16, #1
    and x17, x1, #0xf
@@ -106,6 +109,7 @@ __hwasan_tag_mismatch:
  .type __hwasan_tag_mismatch_v2, %function
  __hwasan_tag_mismatch_v2:
    CFI_STARTPROC
+  BTI_J
  
    // Set the CFA to be the return address for caller of __hwasan_check_*. Note
    // that we do not emit CFI predicates to describe the contents of this stack
@@ -150,3 +154,5 @@ __hwasan_tag_mismatch_v2:
  
  // We do not need executable stack.
  NO_EXEC_STACK_DIRECTIVE
+
+GNU_PROPERTY_BTI_PAC
diff --git a/libsanitizer/hwasan/hwasan_thread.cpp b/libsanitizer/hwasan/hwasan_thread.cpp
index b81a6350c05..bb4d56abed0 100644
--- a/libsanitizer/hwasan/hwasan_thread.cpp
+++ b/libsanitizer/hwasan/hwasan_thread.cpp
@@ -35,6 +35,10 @@ void Thread::InitRandomState() {
  }
  
  void Thread::Init(uptr stack_buffer_start, uptr stack_buffer_size) {
+  CHECK_EQ(0, unique_id_);  // try to catch bad stack reuse
+  CHECK_EQ(0, stack_top_);
+  CHECK_EQ(0, stack_bottom_);
+
    static u64 unique_id;
    unique_id_ = unique_id++;
    if (auto sz = flags()->heap_history_size)
@@ -113,18 +117,21 @@ static u32 xorshift(u32 state) {
  }
  
  // Generate a (pseudo-)random non-zero tag.
-tag_t Thread::GenerateRandomTag() {
+tag_t Thread::GenerateRandomTag(uptr num_bits) {
+  DCHECK_GT(num_bits, 0);
    if (tagging_disabled_) return 0;
    tag_t tag;
+  const uptr tag_mask = (1ULL << num_bits) - 1;
    do {
      if (flags()->random_tags) {
        if (!random_buffer_)
          random_buffer_ = random_state_ = xorshift(random_state_);
        CHECK(random_buffer_);
-      tag = random_buffer_ & 0xFF;
-      random_buffer_ >>= 8;
+      tag = random_buffer_ & tag_mask;
+      random_buffer_ >>= num_bits;
      } else {
-      tag = random_state_ = (random_state_ + 1) & 0xFF;
+      random_state_ += 1;
+      tag = random_state_ & tag_mask;
      }
    } while (!tag);
    return tag;
diff --git a/libsanitizer/hwasan/hwasan_thread.h b/libsanitizer/hwasan/hwasan_thread.h
index ebcdb791fb3..1c71cab41c4 100644
--- a/libsanitizer/hwasan/hwasan_thread.h
+++ b/libsanitizer/hwasan/hwasan_thread.h
@@ -42,7 +42,7 @@ class Thread {
    HeapAllocationsRingBuffer *heap_allocations() { return heap_allocations_; }
    StackAllocationsRingBuffer *stack_allocations() { return stack_allocations_; }
  
-  tag_t GenerateRandomTag();
+  tag_t GenerateRandomTag(uptr num_bits = kTagBits);
  
    void DisableTagging() { tagging_disabled_++; }
    void EnableTagging() { tagging_disabled_--; }
@@ -74,8 +74,6 @@ class Thread {
    HeapAllocationsRingBuffer *heap_allocations_;
    StackAllocationsRingBuffer *stack_allocations_;
  
-  Thread *next_;  // All live threads form a linked list.
-
    u64 unique_id_;  // counting from zero.
  
    u32 tagging_disabled_;  // if non-zero, malloc uses zero tag in this thread.
diff --git a/libsanitizer/hwasan/hwasan_thread_list.h b/libsanitizer/hwasan/hwasan_thread_list.h
index 914b632d977..11c586314ce 100644
--- a/libsanitizer/hwasan/hwasan_thread_list.h
+++ b/libsanitizer/hwasan/hwasan_thread_list.h
@@ -66,40 +66,6 @@ static uptr RingBufferSize() {
    return 0;
  }
  
-struct ThreadListHead {
-  Thread *list_;
-
-  ThreadListHead() : list_(nullptr) {}
-
-  void Push(Thread *t) {
-    t->next_ = list_;
-    list_ = t;
-  }
-
-  Thread *Pop() {
-    Thread *t = list_;
-    if (t)
-      list_ = t->next_;
-    return t;
-  }
-
-  void Remove(Thread *t) {
-    Thread **cur = &list_;
-    while (*cur != t) cur = &(*cur)->next_;
-    CHECK(*cur && "thread not found");
-    *cur = (*cur)->next_;
-  }
-
-  template <class CB>
-  void ForEach(CB cb) {
-    Thread *t = list_;
-    while (t) {
-      cb(t);
-      t = t->next_;
-    }
-  }
-};
-
  struct ThreadStats {
    uptr n_live_threads;
    uptr total_stack_size;
@@ -120,17 +86,23 @@ class HwasanThreadList {
    }
  
    Thread *CreateCurrentThread() {
-    Thread *t;
+    Thread *t = nullptr;
      {
-      SpinMutexLock l(&list_mutex_);
-      t = free_list_.Pop();
-      if (t) {
-        uptr start = (uptr)t - ring_buffer_size_;
-        internal_memset((void *)start, 0, ring_buffer_size_ + sizeof(Thread));
-      } else {
-        t = AllocThread();
+      SpinMutexLock l(&free_list_mutex_);
+      if (!free_list_.empty()) {
+        t = free_list_.back();
+        free_list_.pop_back();
        }
-      live_list_.Push(t);
+    }
+    if (t) {
+      uptr start = (uptr)t - ring_buffer_size_;
+      internal_memset((void *)start, 0, ring_buffer_size_ + sizeof(Thread));
+    } else {
+      t = AllocThread();
+    }
+    {
+      SpinMutexLock l(&live_list_mutex_);
+      live_list_.push_back(t);
      }
      t->Init((uptr)t - ring_buffer_size_, ring_buffer_size_);
      AddThreadStats(t);
@@ -142,13 +114,26 @@ class HwasanThreadList {
      ReleaseMemoryPagesToOS(start, start + thread_alloc_size_);
    }
  
+  void RemoveThreadFromLiveList(Thread *t) {
+    SpinMutexLock l(&live_list_mutex_);
+    for (Thread *&t2 : live_list_)
+      if (t2 == t) {
+        // To remove t2, copy the last element of the list in t2's position, and
+        // pop_back(). This works even if t2 is itself the last element.
+        t2 = live_list_.back();
+        live_list_.pop_back();
+        return;
+      }
+    CHECK(0 && "thread not found in live list");
+  }
+
    void ReleaseThread(Thread *t) {
      RemoveThreadStats(t);
      t->Destroy();
-    SpinMutexLock l(&list_mutex_);
-    live_list_.Remove(t);
-    free_list_.Push(t);
      DontNeedThread(t);
+    RemoveThreadFromLiveList(t);
+    SpinMutexLock l(&free_list_mutex_);
+    free_list_.push_back(t);
    }
  
    Thread *GetThreadByBufferAddress(uptr p) {
@@ -165,8 +150,8 @@ class HwasanThreadList {
  
    template <class CB>
    void VisitAllLiveThreads(CB cb) {
-    SpinMutexLock l(&list_mutex_);
-    live_list_.ForEach(cb);
+    SpinMutexLock l(&live_list_mutex_);
+    for (Thread *t : live_list_) cb(t);
    }
  
    void AddThreadStats(Thread *t) {
@@ -188,6 +173,7 @@ class HwasanThreadList {
  
   private:
    Thread *AllocThread() {
+    SpinMutexLock l(&free_space_mutex_);
      uptr align = ring_buffer_size_ * 2;
      CHECK(IsAligned(free_space_, align));
      Thread *t = (Thread *)(free_space_ + ring_buffer_size_);
@@ -196,14 +182,16 @@ class HwasanThreadList {
      return t;
    }
  
+  SpinMutex free_space_mutex_;
    uptr free_space_;
    uptr free_space_end_;
    uptr ring_buffer_size_;
    uptr thread_alloc_size_;
  
-  ThreadListHead free_list_;
-  ThreadListHead live_list_;
-  SpinMutex list_mutex_;
+  SpinMutex free_list_mutex_;
+  InternalMmapVector<Thread *> free_list_;
+  SpinMutex live_list_mutex_;
+  InternalMmapVector<Thread *> live_list_;
  
    ThreadStats stats_;
    SpinMutex stats_mutex_;
diff --git a/libsanitizer/include/sanitizer/common_interface_defs.h b/libsanitizer/include/sanitizer/common_interface_defs.h
index b4f977bf557..cd69285b8d4 100644
--- a/libsanitizer/include/sanitizer/common_interface_defs.h
+++ b/libsanitizer/include/sanitizer/common_interface_defs.h
@@ -43,6 +43,9 @@ void __sanitizer_set_report_path(const char *path);
  // Tell the tools to write their reports to the provided file descriptor
  // (casted to void *).
  void __sanitizer_set_report_fd(void *fd);
+// Get the current full report file path, if a path was specified by
+// an earlier call to __sanitizer_set_report_path. Returns null otherwise.
+const char *__sanitizer_get_report_path();
  
  // Notify the tools that the sandbox is going to be turned on. The reserved
  // parameter will be used in the future to hold a structure with functions
diff --git a/libsanitizer/include/sanitizer/dfsan_interface.h b/libsanitizer/include/sanitizer/dfsan_interface.h
index 18b2c81a602..40f9379b557 100644
--- a/libsanitizer/include/sanitizer/dfsan_interface.h
+++ b/libsanitizer/include/sanitizer/dfsan_interface.h
@@ -22,6 +22,7 @@ extern "C" {
  #endif
  
  typedef uint16_t dfsan_label;
+typedef uint32_t dfsan_origin;
  
  /// Stores information associated with a specific label identifier.  A label
  /// may be a base label created using dfsan_create_label, with associated
@@ -63,6 +64,12 @@ void dfsan_add_label(dfsan_label label, void *addr, size_t size);
  /// value.
  dfsan_label dfsan_get_label(long data);
  
+/// Retrieves the immediate origin associated with the given data. The returned
+/// origin may point to another origin.
+///
+/// The type of 'data' is arbitrary.
+dfsan_origin dfsan_get_origin(long data);
+
  /// Retrieves the label associated with the data at the given address.
  dfsan_label dfsan_read_label(const void *addr, size_t size);
  
@@ -110,6 +117,15 @@ void dfsan_weak_hook_memcmp(void *caller_pc, const void *s1, const void *s2,
  void dfsan_weak_hook_strncmp(void *caller_pc, const char *s1, const char *s2,
                               size_t n, dfsan_label s1_label,
                               dfsan_label s2_label, dfsan_label n_label);
+
+/// Prints the origin trace of the label at the address addr to stderr. It also
+/// prints description at the beginning of the trace. If origin tracking is not
+/// on, or the address is not labeled, it prints nothing.
+void dfsan_print_origin_trace(const void *addr, const char *description);
+
+/// Retrieves the very first origin associated with the data at the given
+/// address.
+dfsan_origin dfsan_get_init_origin(const void *addr);
  #ifdef __cplusplus
  }  // extern "C"
  
diff --git a/libsanitizer/include/sanitizer/hwasan_interface.h b/libsanitizer/include/sanitizer/hwasan_interface.h
index 4c9ad13aa0c..14035c05c63 100644
--- a/libsanitizer/include/sanitizer/hwasan_interface.h
+++ b/libsanitizer/include/sanitizer/hwasan_interface.h
@@ -73,6 +73,9 @@ extern "C" {
     * accessed through the pointer in x, or -1 if the whole range is good. */
    intptr_t __hwasan_test_shadow(const volatile void *x, size_t size);
  
+  /* Sets the callback function to be called during HWASan error reporting. */
+  void __hwasan_set_error_report_callback(void (*callback)(const char *));
+
    int __sanitizer_posix_memalign(void **memptr, size_t alignment, size_t size);
    void * __sanitizer_memalign(size_t alignment, size_t size);
    void * __sanitizer_aligned_alloc(size_t alignment, size_t size);
diff --git a/libsanitizer/include/sanitizer/memprof_interface.h b/libsanitizer/include/sanitizer/memprof_interface.h
index a7212605100..76031de4014 100644
--- a/libsanitizer/include/sanitizer/memprof_interface.h
+++ b/libsanitizer/include/sanitizer/memprof_interface.h
@@ -53,6 +53,11 @@ void __memprof_print_accumulated_stats(void);
  /// \returns Default options string.
  const char *__memprof_default_options(void);
  
+/// Prints the memory profile to the current profile file.
+///
+/// \returns 0 on success.
+int __memprof_profile_dump(void);
+
  #ifdef __cplusplus
  } // extern "C"
  #endif
diff --git a/libsanitizer/include/sanitizer/tsan_interface.h b/libsanitizer/include/sanitizer/tsan_interface.h
index 96b8ad58541..565aa391a9f 100644
--- a/libsanitizer/include/sanitizer/tsan_interface.h
+++ b/libsanitizer/include/sanitizer/tsan_interface.h
@@ -67,6 +67,12 @@ static const unsigned __tsan_mutex_recursive_lock   = 1 << 6;
  // the corresponding __tsan_mutex_post_lock annotation.
  static const unsigned __tsan_mutex_recursive_unlock = 1 << 7;
  
+// Convenient composed constants.
+static const unsigned __tsan_mutex_try_read_lock =
+    __tsan_mutex_read_lock | __tsan_mutex_try_lock;
+static const unsigned __tsan_mutex_try_read_lock_failed =
+    __tsan_mutex_try_read_lock | __tsan_mutex_try_lock_failed;
+
  // Annotate creation of a mutex.
  // Supported flags: mutex creation flags.
  void __tsan_mutex_create(void *addr, unsigned flags);
@@ -141,7 +147,7 @@ void __tsan_external_write(void *addr, void *caller_pc, void *tag);
  //     and freed by __tsan_destroy_fiber.
  //   - TSAN context of current fiber or thread can be obtained
  //     by calling __tsan_get_current_fiber.
-//   - __tsan_switch_to_fiber should be called immediatly before switch
+//   - __tsan_switch_to_fiber should be called immediately before switch
  //     to fiber, such as call of swapcontext.
  //   - Fiber name can be set by __tsan_set_fiber_name.
  void *__tsan_get_current_fiber(void);
@@ -154,6 +160,15 @@ void __tsan_set_fiber_name(void *fiber, const char *name);
  // Do not establish a happens-before relation between fibers
  static const unsigned __tsan_switch_to_fiber_no_sync = 1 << 0;
  
+// User-provided callback invoked on TSan initialization.
+void __tsan_on_initialize();
+
+// User-provided callback invoked on TSan shutdown.
+// `failed` - Nonzero if TSan did detect issues, zero otherwise.
+// Return `0` if TSan should exit as if no issues were detected.  Return nonzero
+// if TSan should exit as if issues were detected.
+int __tsan_on_finalize(int failed);
+
  #ifdef __cplusplus
  }  // extern "C"
  #endif
diff --git a/libsanitizer/include/sanitizer/tsan_interface_atomic.h b/libsanitizer/include/sanitizer/tsan_interface_atomic.h
index 8052bc1d56b..5e41e2256c3 100644
--- a/libsanitizer/include/sanitizer/tsan_interface_atomic.h
+++ b/libsanitizer/include/sanitizer/tsan_interface_atomic.h
@@ -30,7 +30,7 @@ __extension__ typedef __int128 __tsan_atomic128;
  #endif
  
  // Part of ABI, do not change.
-// https://github.com/llvm/llvm-project/blob/master/libcxx/include/atomic
+// https://github.com/llvm/llvm-project/blob/main/libcxx/include/atomic
  typedef enum {
    __tsan_memory_order_relaxed,
    __tsan_memory_order_consume,
diff --git a/libsanitizer/interception/interception_linux.cpp b/libsanitizer/interception/interception_linux.cpp
index 6883608d44f..5111a87f0a6 100644
--- a/libsanitizer/interception/interception_linux.cpp
+++ b/libsanitizer/interception/interception_linux.cpp
@@ -63,8 +63,8 @@ bool InterceptFunction(const char *name, uptr *ptr_to_real, uptr func,
    return addr && (func == wrapper);
  }
  
-// Android and Solaris do not have dlvsym
-#if !SANITIZER_ANDROID && !SANITIZER_SOLARIS
+// dlvsym is a GNU extension supported by some other platforms.
+#if SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
  static void *GetFuncAddr(const char *name, const char *ver) {
    return dlvsym(RTLD_NEXT, name, ver);
  }
@@ -75,7 +75,7 @@ bool InterceptFunction(const char *name, const char *ver, uptr *ptr_to_real,
    *ptr_to_real = (uptr)addr;
    return addr && (func == wrapper);
  }
-#endif  // !SANITIZER_ANDROID
+#endif  // SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
  
  }  // namespace __interception
  
diff --git a/libsanitizer/interception/interception_linux.h b/libsanitizer/interception/interception_linux.h
index 097375fd1c1..a08f8cb98c4 100644
--- a/libsanitizer/interception/interception_linux.h
+++ b/libsanitizer/interception/interception_linux.h
@@ -35,8 +35,8 @@ bool InterceptFunction(const char *name, const char *ver, uptr *ptr_to_real,
        (::__interception::uptr) & (func),          \
        (::__interception::uptr) & WRAP(func))
  
-// Android and Solaris do not have dlvsym
-#if !SANITIZER_ANDROID && !SANITIZER_SOLARIS
+// dlvsym is a GNU extension supported by some other platforms.
+#if SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
  #define INTERCEPT_FUNCTION_VER_LINUX_OR_FREEBSD(func, symver) \
    ::__interception::InterceptFunction(                        \
        #func, symver,                                          \
@@ -46,7 +46,7 @@ bool InterceptFunction(const char *name, const char *ver, uptr *ptr_to_real,
  #else
  #define INTERCEPT_FUNCTION_VER_LINUX_OR_FREEBSD(func, symver) \
    INTERCEPT_FUNCTION_LINUX_OR_FREEBSD(func)
-#endif  // !SANITIZER_ANDROID && !SANITIZER_SOLARIS
+#endif  // SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
  
  #endif  // INTERCEPTION_LINUX_H
  #endif  // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD ||
diff --git a/libsanitizer/interception/interception_win.cpp b/libsanitizer/interception/interception_win.cpp
index 1a1c327e612..98bc756ae53 100644
--- a/libsanitizer/interception/interception_win.cpp
+++ b/libsanitizer/interception/interception_win.cpp
@@ -136,7 +136,7 @@ namespace __interception {
  static const int kAddressLength = FIRST_32_SECOND_64(4, 8);
  static const int kJumpInstructionLength = 5;
  static const int kShortJumpInstructionLength = 2;
-static const int kIndirectJumpInstructionLength = 6;
+UNUSED static const int kIndirectJumpInstructionLength = 6;
  static const int kBranchLength =
      FIRST_32_SECOND_64(kJumpInstructionLength, kIndirectJumpInstructionLength);
  static const int kDirectBranchLength = kBranchLength + kAddressLength;
@@ -165,7 +165,7 @@ static uptr GetMmapGranularity() {
    return si.dwAllocationGranularity;
  }
  
-static uptr RoundUpTo(uptr size, uptr boundary) {
+UNUSED static uptr RoundUpTo(uptr size, uptr boundary) {
    return (size + boundary - 1) & ~(boundary - 1);
  }
  
@@ -309,7 +309,7 @@ struct TrampolineMemoryRegion {
    uptr max_size;
  };
  
-static const uptr kTrampolineScanLimitRange = 1 << 31;  // 2 gig
+UNUSED static const uptr kTrampolineScanLimitRange = 1 << 31;  // 2 gig
  static const int kMaxTrampolineRegion = 1024;
  static TrampolineMemoryRegion TrampolineRegions[kMaxTrampolineRegion];
  
diff --git a/libsanitizer/lsan/lsan_allocator.cpp b/libsanitizer/lsan/lsan_allocator.cpp
index d86c3921395..91e34ebb321 100644
--- a/libsanitizer/lsan/lsan_allocator.cpp
+++ b/libsanitizer/lsan/lsan_allocator.cpp
@@ -123,14 +123,18 @@ void Deallocate(void *p) {
  
  void *Reallocate(const StackTrace &stack, void *p, uptr new_size,
                   uptr alignment) {
-  RegisterDeallocation(p);
    if (new_size > max_malloc_size) {
-    allocator.Deallocate(GetAllocatorCache(), p);
-    return ReportAllocationSizeTooBig(new_size, stack);
+    ReportAllocationSizeTooBig(new_size, stack);
+    return nullptr;
    }
-  p = allocator.Reallocate(GetAllocatorCache(), p, new_size, alignment);
-  RegisterAllocation(stack, p, new_size);
-  return p;
+  RegisterDeallocation(p);
+  void *new_p =
+      allocator.Reallocate(GetAllocatorCache(), p, new_size, alignment);
+  if (new_p)
+    RegisterAllocation(stack, new_p, new_size);
+  else if (new_size != 0)
+    RegisterAllocation(stack, p, new_size);
+  return new_p;
  }
  
  void GetAllocatorCacheRange(uptr *begin, uptr *end) {
@@ -309,6 +313,16 @@ IgnoreObjectResult IgnoreObjectLocked(const void *p) {
      return kIgnoreObjectInvalid;
    }
  }
+
+void GetAdditionalThreadContextPtrs(ThreadContextBase *tctx, void *ptrs) {
+  // This function can be used to treat memory reachable from `tctx` as live.
+  // This is useful for threads that have been created but not yet started.
+
+  // This is currently a no-op because the LSan `pthread_create()` interceptor
+  // blocks until the child thread starts which keeps the thread's `arg` pointer
+  // live.
+}
+
  } // namespace __lsan
  
  using namespace __lsan;
diff --git a/libsanitizer/lsan/lsan_allocator.h b/libsanitizer/lsan/lsan_allocator.h
index 17e13cd014b..9d763789154 100644
--- a/libsanitizer/lsan/lsan_allocator.h
+++ b/libsanitizer/lsan/lsan_allocator.h
@@ -50,7 +50,7 @@ struct ChunkMetadata {
  };
  
  #if defined(__mips64) || defined(__aarch64__) || defined(__i386__) || \
-    defined(__arm__)
+    defined(__arm__) || SANITIZER_RISCV64
  template <typename AddressSpaceViewTy>
  struct AP32 {
    static const uptr kSpaceBeg = 0;
diff --git a/libsanitizer/lsan/lsan_common.cpp b/libsanitizer/lsan/lsan_common.cpp
index 9e23aa9997a..74400d2e842 100644
--- a/libsanitizer/lsan/lsan_common.cpp
+++ b/libsanitizer/lsan/lsan_common.cpp
@@ -65,8 +65,34 @@ void RegisterLsanFlags(FlagParser *parser, Flags *f) {
      if (flags()->log_threads) Report(__VA_ARGS__); \
    } while (0)
  
-ALIGNED(64) static char suppression_placeholder[sizeof(SuppressionContext)];
-static SuppressionContext *suppression_ctx = nullptr;
+class LeakSuppressionContext {
+  bool parsed = false;
+  SuppressionContext context;
+  bool suppressed_stacks_sorted = true;
+  InternalMmapVector<u32> suppressed_stacks;
+
+  Suppression *GetSuppressionForAddr(uptr addr);
+  void LazyInit();
+
+ public:
+  LeakSuppressionContext(const char *supprression_types[],
+                         int suppression_types_num)
+      : context(supprression_types, suppression_types_num) {}
+
+  Suppression *GetSuppressionForStack(u32 stack_trace_id);
+
+  const InternalMmapVector<u32> &GetSortedSuppressedStacks() {
+    if (!suppressed_stacks_sorted) {
+      suppressed_stacks_sorted = true;
+      SortAndDedup(suppressed_stacks);
+    }
+    return suppressed_stacks;
+  }
+  void PrintMatchedSuppressions();
+};
+
+ALIGNED(64) static char suppression_placeholder[sizeof(LeakSuppressionContext)];
+static LeakSuppressionContext *suppression_ctx = nullptr;
  static const char kSuppressionLeak[] = "leak";
  static const char *kSuppressionTypes[] = { kSuppressionLeak };
  static const char kStdSuppressions[] =
@@ -86,14 +112,20 @@ static const char kStdSuppressions[] =
  void InitializeSuppressions() {
    CHECK_EQ(nullptr, suppression_ctx);
    suppression_ctx = new (suppression_placeholder)
-      SuppressionContext(kSuppressionTypes, ARRAY_SIZE(kSuppressionTypes));
-  suppression_ctx->ParseFromFile(flags()->suppressions);
-  if (&__lsan_default_suppressions)
-    suppression_ctx->Parse(__lsan_default_suppressions());
-  suppression_ctx->Parse(kStdSuppressions);
+      LeakSuppressionContext(kSuppressionTypes, ARRAY_SIZE(kSuppressionTypes));
+}
+
+void LeakSuppressionContext::LazyInit() {
+  if (!parsed) {
+    parsed = true;
+    context.ParseFromFile(flags()->suppressions);
+    if (&__lsan_default_suppressions)
+      context.Parse(__lsan_default_suppressions());
+    context.Parse(kStdSuppressions);
+  }
  }
  
-static SuppressionContext *GetSuppressionContext() {
+static LeakSuppressionContext *GetSuppressionContext() {
    CHECK(suppression_ctx);
    return suppression_ctx;
  }
@@ -221,6 +253,27 @@ extern "C" SANITIZER_WEAK_ATTRIBUTE void __libc_iterate_dynamic_tls(
      pid_t, void (*cb)(void *, void *, uptr, void *), void *);
  #endif
  
+static void ProcessThreadRegistry(Frontier *frontier) {
+  InternalMmapVector<uptr> ptrs;
+  GetThreadRegistryLocked()->RunCallbackForEachThreadLocked(
+      GetAdditionalThreadContextPtrs, &ptrs);
+
+  for (uptr i = 0; i < ptrs.size(); ++i) {
+    void *ptr = reinterpret_cast<void *>(ptrs[i]);
+    uptr chunk = PointsIntoChunk(ptr);
+    if (!chunk)
+      continue;
+    LsanMetadata m(chunk);
+    if (!m.allocated())
+      continue;
+
+    // Mark as reachable and add to frontier.
+    LOG_POINTERS("Treating pointer %p from ThreadContext as reachable\n", ptr);
+    m.set_tag(kReachable);
+    frontier->push_back(chunk);
+  }
+}
+
  // Scans thread data (stacks and TLS) for heap pointers.
  static void ProcessThreads(SuspendedThreadsList const &suspended_threads,
                             Frontier *frontier) {
@@ -315,15 +368,15 @@ static void ProcessThreads(SuspendedThreadsList const &suspended_threads,
        __libc_iterate_dynamic_tls(os_id, cb, frontier);
  #else
        if (dtls && !DTLSInDestruction(dtls)) {
-        for (uptr j = 0; j < dtls->dtv_size; ++j) {
-          uptr dtls_beg = dtls->dtv[j].beg;
-          uptr dtls_end = dtls_beg + dtls->dtv[j].size;
+        ForEachDVT(dtls, [&](const DTLS::DTV &dtv, int id) {
+          uptr dtls_beg = dtv.beg;
+          uptr dtls_end = dtls_beg + dtv.size;
            if (dtls_beg < dtls_end) {
-            LOG_THREADS("DTLS %zu at %p-%p.\n", j, dtls_beg, dtls_end);
+            LOG_THREADS("DTLS %zu at %p-%p.\n", id, dtls_beg, dtls_end);
              ScanRangeForPointers(dtls_beg, dtls_end, frontier, "DTLS",
                                   kReachable);
            }
-        }
+        });
        } else {
          // We are handling a thread with DTLS under destruction. Log about
          // this and continue.
@@ -332,6 +385,9 @@ static void ProcessThreads(SuspendedThreadsList const &suspended_threads,
  #endif
      }
    }
+
+  // Add pointers reachable from ThreadContexts
+  ProcessThreadRegistry(frontier);
  }
  
  #endif  // SANITIZER_FUCHSIA
@@ -390,6 +446,24 @@ static void MarkIndirectlyLeakedCb(uptr chunk, void *arg) {
    }
  }
  
+static void IgnoredSuppressedCb(uptr chunk, void *arg) {
+  CHECK(arg);
+  chunk = GetUserBegin(chunk);
+  LsanMetadata m(chunk);
+  if (!m.allocated() || m.tag() == kIgnored)
+    return;
+
+  const InternalMmapVector<u32> &suppressed =
+      *static_cast<const InternalMmapVector<u32> *>(arg);
+  uptr idx = InternalLowerBound(suppressed, m.stack_trace_id());
+  if (idx >= suppressed.size() || m.stack_trace_id() != suppressed[idx])
+    return;
+
+  LOG_POINTERS("Suppressed: chunk %p-%p of size %zu.\n", chunk,
+               chunk + m.requested_size(), m.requested_size());
+  m.set_tag(kIgnored);
+}
+
  // ForEachChunk callback. If chunk is marked as ignored, adds its address to
  // frontier.
  static void CollectIgnoredCb(uptr chunk, void *arg) {
@@ -473,6 +547,12 @@ void ProcessPC(Frontier *frontier) {
  // Sets the appropriate tag on each chunk.
  static void ClassifyAllChunks(SuspendedThreadsList const &suspended_threads,
                                Frontier *frontier) {
+  const InternalMmapVector<u32> &suppressed_stacks =
+      GetSuppressionContext()->GetSortedSuppressedStacks();
+  if (!suppressed_stacks.empty()) {
+    ForEachChunk(IgnoredSuppressedCb,
+                 const_cast<InternalMmapVector<u32> *>(&suppressed_stacks));
+  }
    ForEachChunk(CollectIgnoredCb, frontier);
    ProcessGlobalRegions(frontier);
    ProcessThreads(suspended_threads, frontier);
@@ -532,18 +612,20 @@ static void CollectLeaksCb(uptr chunk, void *arg) {
    }
  }
  
-static void PrintMatchedSuppressions() {
+void LeakSuppressionContext::PrintMatchedSuppressions() {
    InternalMmapVector<Suppression *> matched;
-  GetSuppressionContext()->GetMatched(&matched);
+  context.GetMatched(&matched);
    if (!matched.size())
      return;
    const char *line = "-----------------------------------------------------";
    Printf("%s\n", line);
    Printf("Suppressions used:\n");
    Printf("  count      bytes template\n");
-  for (uptr i = 0; i < matched.size(); i++)
-    Printf("%7zu %10zu %s\n", static_cast<uptr>(atomic_load_relaxed(
-        &matched[i]->hit_count)), matched[i]->weight, matched[i]->templ);
+  for (uptr i = 0; i < matched.size(); i++) {
+    Printf("%7zu %10zu %s\n",
+           static_cast<uptr>(atomic_load_relaxed(&matched[i]->hit_count)),
+           matched[i]->weight, matched[i]->templ);
+  }
    Printf("%s\n\n", line);
  }
  
@@ -551,8 +633,7 @@ static void ReportIfNotSuspended(ThreadContextBase *tctx, void *arg) {
    const InternalMmapVector<tid_t> &suspended_threads =
        *(const InternalMmapVector<tid_t> *)arg;
    if (tctx->status == ThreadStatusRunning) {
-    uptr i = InternalLowerBound(suspended_threads, 0, suspended_threads.size(),
-                                tctx->os_id, CompareLess<int>());
+    uptr i = InternalLowerBound(suspended_threads, tctx->os_id);
      if (i >= suspended_threads.size() || suspended_threads[i] != tctx->os_id)
        Report("Running thread %d was not suspended. False leaks are possible.\n",
               tctx->os_id);
@@ -595,43 +676,68 @@ static void CheckForLeaksCallback(const SuspendedThreadsList &suspended_threads,
    param->success = true;
  }
  
-static bool CheckForLeaks() {
-  if (&__lsan_is_turned_off && __lsan_is_turned_off())
-    return false;
-  EnsureMainThreadIDIsCorrect();
-  CheckForLeaksParam param;
-  LockStuffAndStopTheWorld(CheckForLeaksCallback, &param);
-
-  if (!param.success) {
-    Report("LeakSanitizer has encountered a fatal error.\n");
-    Report(
-        "HINT: For debugging, try setting environment variable "
-        "LSAN_OPTIONS=verbosity=1:log_threads=1\n");
-    Report(
-        "HINT: LeakSanitizer does not work under ptrace (strace, gdb, etc)\n");
-    Die();
-  }
-  param.leak_report.ApplySuppressions();
-  uptr unsuppressed_count = param.leak_report.UnsuppressedLeakCount();
-  if (unsuppressed_count > 0) {
+static bool PrintResults(LeakReport &report) {
+  uptr unsuppressed_count = report.UnsuppressedLeakCount();
+  if (unsuppressed_count) {
      Decorator d;
-    Printf("\n"
-           "================================================================="
-           "\n");
+    Printf(
+        "\n"
+        "================================================================="
+        "\n");
      Printf("%s", d.Error());
      Report("ERROR: LeakSanitizer: detected memory leaks\n");
      Printf("%s", d.Default());
-    param.leak_report.ReportTopLeaks(flags()->max_leaks);
+    report.ReportTopLeaks(flags()->max_leaks);
    }
    if (common_flags()->print_suppressions)
-    PrintMatchedSuppressions();
+    GetSuppressionContext()->PrintMatchedSuppressions();
    if (unsuppressed_count > 0) {
-    param.leak_report.PrintSummary();
+    report.PrintSummary();
      return true;
    }
    return false;
  }
  
+static bool CheckForLeaks() {
+  if (&__lsan_is_turned_off && __lsan_is_turned_off())
+    return false;
+  // Inside LockStuffAndStopTheWorld we can't run symbolizer, so we can't match
+  // suppressions. However if a stack id was previously suppressed, it should be
+  // suppressed in future checks as well.
+  for (int i = 0;; ++i) {
+    EnsureMainThreadIDIsCorrect();
+    CheckForLeaksParam param;
+    LockStuffAndStopTheWorld(CheckForLeaksCallback, &param);
+    if (!param.success) {
+      Report("LeakSanitizer has encountered a fatal error.\n");
+      Report(
+          "HINT: For debugging, try setting environment variable "
+          "LSAN_OPTIONS=verbosity=1:log_threads=1\n");
+      Report(
+          "HINT: LeakSanitizer does not work under ptrace (strace, gdb, "
+          "etc)\n");
+      Die();
+    }
+    // No new suppressions stacks, so rerun will not help and we can report.
+    if (!param.leak_report.ApplySuppressions())
+      return PrintResults(param.leak_report);
+
+    // No indirect leaks to report, so we are done here.
+    if (!param.leak_report.IndirectUnsuppressedLeakCount())
+      return PrintResults(param.leak_report);
+
+    if (i >= 8) {
+      Report("WARNING: LeakSanitizer gave up on indirect leaks suppression.\n");
+      return PrintResults(param.leak_report);
+    }
+
+    // We found a new previously unseen suppressed call stack. Rerun to make
+    // sure it does not hold indirect leaks.
+    VReport(1, "Rerun with %zu suppressed stacks.",
+            GetSuppressionContext()->GetSortedSuppressedStacks().size());
+  }
+}
+
  static bool has_reported_leaks = false;
  bool HasReportedLeaks() { return has_reported_leaks; }
  
@@ -652,21 +758,20 @@ static int DoRecoverableLeakCheck() {
  
  void DoRecoverableLeakCheckVoid() { DoRecoverableLeakCheck(); }
  
-static Suppression *GetSuppressionForAddr(uptr addr) {
+Suppression *LeakSuppressionContext::GetSuppressionForAddr(uptr addr) {
    Suppression *s = nullptr;
  
    // Suppress by module name.
-  SuppressionContext *suppressions = GetSuppressionContext();
    if (const char *module_name =
            Symbolizer::GetOrInit()->GetModuleNameForPc(addr))
-    if (suppressions->Match(module_name, kSuppressionLeak, &s))
+    if (context.Match(module_name, kSuppressionLeak, &s))
        return s;
  
    // Suppress by file or function name.
    SymbolizedStack *frames = Symbolizer::GetOrInit()->SymbolizePC(addr);
    for (SymbolizedStack *cur = frames; cur; cur = cur->next) {
-    if (suppressions->Match(cur->info.function, kSuppressionLeak, &s) ||
-        suppressions->Match(cur->info.file, kSuppressionLeak, &s)) {
+    if (context.Match(cur->info.function, kSuppressionLeak, &s) ||
+        context.Match(cur->info.file, kSuppressionLeak, &s)) {
        break;
      }
    }
@@ -674,12 +779,18 @@ static Suppression *GetSuppressionForAddr(uptr addr) {
    return s;
  }
  
-static Suppression *GetSuppressionForStack(u32 stack_trace_id) {
+Suppression *LeakSuppressionContext::GetSuppressionForStack(
+    u32 stack_trace_id) {
+  LazyInit();
    StackTrace stack = StackDepotGet(stack_trace_id);
    for (uptr i = 0; i < stack.size; i++) {
      Suppression *s = GetSuppressionForAddr(
          StackTrace::GetPreviousInstructionPc(stack.trace[i]));
-    if (s) return s;
+    if (s) {
+      suppressed_stacks_sorted = false;
+      suppressed_stacks.push_back(stack_trace_id);
+      return s;
+    }
    }
    return nullptr;
  }
@@ -784,22 +895,27 @@ void LeakReport::PrintSummary() {
        bytes += leaks_[i].total_size;
        allocations += leaks_[i].hit_count;
    }
-  InternalScopedString summary(kMaxSummaryLength);
+  InternalScopedString summary;
    summary.append("%zu byte(s) leaked in %zu allocation(s).", bytes,
                   allocations);
    ReportErrorSummary(summary.data());
  }
  
-void LeakReport::ApplySuppressions() {
+uptr LeakReport::ApplySuppressions() {
+  LeakSuppressionContext *suppressions = GetSuppressionContext();
+  uptr new_suppressions = false;
    for (uptr i = 0; i < leaks_.size(); i++) {
-    Suppression *s = GetSuppressionForStack(leaks_[i].stack_trace_id);
+    Suppression *s =
+        suppressions->GetSuppressionForStack(leaks_[i].stack_trace_id);
      if (s) {
        s->weight += leaks_[i].total_size;
        atomic_store_relaxed(&s->hit_count, atomic_load_relaxed(&s->hit_count) +
            leaks_[i].hit_count);
        leaks_[i].is_suppressed = true;
+      ++new_suppressions;
      }
    }
+  return new_suppressions;
  }
  
  uptr LeakReport::UnsuppressedLeakCount() {
@@ -809,6 +925,14 @@ uptr LeakReport::UnsuppressedLeakCount() {
    return result;
  }
  
+uptr LeakReport::IndirectUnsuppressedLeakCount() {
+  uptr result = 0;
+  for (uptr i = 0; i < leaks_.size(); i++)
+    if (!leaks_[i].is_suppressed && !leaks_[i].is_directly_leaked)
+      result++;
+  return result;
+}
+
  } // namespace __lsan
  #else // CAN_SANITIZE_LEAKS
  namespace __lsan {
diff --git a/libsanitizer/lsan/lsan_common.h b/libsanitizer/lsan/lsan_common.h
index 1fdce087b3a..fe855cf3754 100644
--- a/libsanitizer/lsan/lsan_common.h
+++ b/libsanitizer/lsan/lsan_common.h
@@ -41,6 +41,8 @@
  #define CAN_SANITIZE_LEAKS 1
  #elif defined(__arm__) && SANITIZER_LINUX
  #define CAN_SANITIZE_LEAKS 1
+#elif SANITIZER_RISCV64 && SANITIZER_LINUX
+#define CAN_SANITIZE_LEAKS 1
  #elif SANITIZER_NETBSD || SANITIZER_FUCHSIA
  #define CAN_SANITIZE_LEAKS 1
  #else
@@ -50,6 +52,7 @@
  namespace __sanitizer {
  class FlagParser;
  class ThreadRegistry;
+class ThreadContextBase;
  struct DTLS;
  }
  
@@ -63,8 +66,6 @@ enum ChunkTag {
    kIgnored = 3
  };
  
-const u32 kInvalidTid = (u32) -1;
-
  struct Flags {
  #define LSAN_FLAG(Type, Name, DefaultValue, Description) Type Name;
  #include "lsan_flags.inc"
@@ -103,8 +104,9 @@ class LeakReport {
                        ChunkTag tag);
    void ReportTopLeaks(uptr max_leaks);
    void PrintSummary();
-  void ApplySuppressions();
+  uptr ApplySuppressions();
    uptr UnsuppressedLeakCount();
+  uptr IndirectUnsuppressedLeakCount();
  
   private:
    void PrintReportForLeak(uptr index);
@@ -141,6 +143,7 @@ InternalMmapVector<RootRegion> const *GetRootRegions();
  void ScanRootRegion(Frontier *frontier, RootRegion const &region,
                      uptr region_begin, uptr region_end, bool is_readable);
  void ForEachExtraStackRangeCb(uptr begin, uptr end, void* arg);
+void GetAdditionalThreadContextPtrs(ThreadContextBase *tctx, void *ptrs);
  // Run stoptheworld while holding any platform-specific locks, as well as the
  // allocator and thread registry locks.
  void LockStuffAndStopTheWorld(StopTheWorldCallback callback,
diff --git a/libsanitizer/lsan/lsan_common_fuchsia.cpp b/libsanitizer/lsan/lsan_common_fuchsia.cpp
index 3c62c9433d3..2d35fa5b1cf 100644
--- a/libsanitizer/lsan/lsan_common_fuchsia.cpp
+++ b/libsanitizer/lsan/lsan_common_fuchsia.cpp
@@ -107,9 +107,7 @@ void LockStuffAndStopTheWorld(StopTheWorldCallback callback,
      auto params = static_cast<const Params *>(data);
      uptr begin = reinterpret_cast<uptr>(chunk);
      uptr end = begin + size;
-    auto i = __sanitizer::InternalLowerBound(params->allocator_caches, 0,
-                                             params->allocator_caches.size(),
-                                             begin, CompareLess<uptr>());
+    auto i = __sanitizer::InternalLowerBound(params->allocator_caches, begin);
      if (i < params->allocator_caches.size() &&
          params->allocator_caches[i] >= begin &&
          end - params->allocator_caches[i] <= sizeof(AllocatorCache)) {
diff --git a/libsanitizer/lsan/lsan_fuchsia.h b/libsanitizer/lsan/lsan_fuchsia.h
index 65d20ea2114..e730d8f25f2 100644
--- a/libsanitizer/lsan/lsan_fuchsia.h
+++ b/libsanitizer/lsan/lsan_fuchsia.h
@@ -23,7 +23,7 @@
  
  namespace __lsan {
  
-class ThreadContext : public ThreadContextLsanBase {
+class ThreadContext final : public ThreadContextLsanBase {
   public:
    explicit ThreadContext(int tid);
    void OnCreated(void *arg) override;
diff --git a/libsanitizer/lsan/lsan_interceptors.cpp b/libsanitizer/lsan/lsan_interceptors.cpp
index bf8d316770e..90a90a56c54 100644
--- a/libsanitizer/lsan/lsan_interceptors.cpp
+++ b/libsanitizer/lsan/lsan_interceptors.cpp
@@ -460,7 +460,7 @@ INTERCEPTOR(int, pthread_create, void *th, void *attr,
    if (res == 0) {
      int tid = ThreadCreate(GetCurrentThread(), *(uptr *)th,
                             IsStateDetached(detached));
-    CHECK_NE(tid, 0);
+    CHECK_NE(tid, kMainTid);
      atomic_store(&p.tid, tid, memory_order_release);
      while (atomic_load(&p.tid, memory_order_acquire) != 0)
        internal_sched_yield();
diff --git a/libsanitizer/lsan/lsan_posix.cpp b/libsanitizer/lsan/lsan_posix.cpp
index 8e05915dd1b..5d1c3f6260d 100644
--- a/libsanitizer/lsan/lsan_posix.cpp
+++ b/libsanitizer/lsan/lsan_posix.cpp
@@ -48,7 +48,7 @@ void ThreadStart(u32 tid, tid_t os_id, ThreadType thread_type) {
    OnStartedArgs args;
    uptr stack_size = 0;
    uptr tls_size = 0;
-  GetThreadStackAndTls(tid == 0, &args.stack_begin, &stack_size,
+  GetThreadStackAndTls(tid == kMainTid, &args.stack_begin, &stack_size,
                         &args.tls_begin, &tls_size);
    args.stack_end = args.stack_begin + stack_size;
    args.tls_end = args.tls_begin + tls_size;
@@ -75,8 +75,8 @@ bool GetThreadRangesLocked(tid_t os_id, uptr *stack_begin, uptr *stack_end,
  }
  
  void InitializeMainThread() {
-  u32 tid = ThreadCreate(0, 0, true);
-  CHECK_EQ(tid, 0);
+  u32 tid = ThreadCreate(kMainTid, 0, true);
+  CHECK_EQ(tid, kMainTid);
    ThreadStart(tid, GetTid());
  }
  
diff --git a/libsanitizer/lsan/lsan_thread.cpp b/libsanitizer/lsan/lsan_thread.cpp
index 371a1f29dfe..8efb54a6fb7 100644
--- a/libsanitizer/lsan/lsan_thread.cpp
+++ b/libsanitizer/lsan/lsan_thread.cpp
@@ -94,7 +94,7 @@ void ThreadJoin(u32 tid) {
  }
  
  void EnsureMainThreadIDIsCorrect() {
-  if (GetCurrentThread() == 0)
+  if (GetCurrentThread() == kMainTid)
      CurrentThreadContext()->os_id = GetTid();
  }
  
diff --git a/libsanitizer/sanitizer_common/sanitizer_allocator_combined.h b/libsanitizer/sanitizer_common/sanitizer_allocator_combined.h
index 33f89d6d499..eb836bc4787 100644
--- a/libsanitizer/sanitizer_common/sanitizer_allocator_combined.h
+++ b/libsanitizer/sanitizer_common/sanitizer_allocator_combined.h
@@ -35,9 +35,9 @@ class CombinedAllocator {
      secondary_.InitLinkerInitialized();
    }
  
-  void Init(s32 release_to_os_interval_ms) {
+  void Init(s32 release_to_os_interval_ms, uptr heap_start = 0) {
      stats_.Init();
-    primary_.Init(release_to_os_interval_ms);
+    primary_.Init(release_to_os_interval_ms, heap_start);
      secondary_.Init();
    }
  
diff --git a/libsanitizer/sanitizer_common/sanitizer_allocator_primary32.h b/libsanitizer/sanitizer_common/sanitizer_allocator_primary32.h
index b90dabbf776..fb5394cd39c 100644
--- a/libsanitizer/sanitizer_common/sanitizer_allocator_primary32.h
+++ b/libsanitizer/sanitizer_common/sanitizer_allocator_primary32.h
@@ -119,7 +119,8 @@ class SizeClassAllocator32 {
    typedef SizeClassAllocator32<Params> ThisT;
    typedef SizeClassAllocator32LocalCache<ThisT> AllocatorCache;
  
-  void Init(s32 release_to_os_interval_ms) {
+  void Init(s32 release_to_os_interval_ms, uptr heap_start = 0) {
+    CHECK(!heap_start);
      possible_regions.Init();
      internal_memset(size_class_info_array, 0, sizeof(size_class_info_array));
    }
diff --git a/libsanitizer/sanitizer_common/sanitizer_allocator_primary64.h b/libsanitizer/sanitizer_common/sanitizer_allocator_primary64.h
index 0a18b0c58ef..db30e138154 100644
--- a/libsanitizer/sanitizer_common/sanitizer_allocator_primary64.h
+++ b/libsanitizer/sanitizer_common/sanitizer_allocator_primary64.h
@@ -19,7 +19,7 @@ template<class SizeClassAllocator> struct SizeClassAllocator64LocalCache;
  // The template parameter Params is a class containing the actual parameters.
  //
  // Space: a portion of address space of kSpaceSize bytes starting at SpaceBeg.
-// If kSpaceBeg is ~0 then SpaceBeg is chosen dynamically my mmap.
+// If kSpaceBeg is ~0 then SpaceBeg is chosen dynamically by mmap.
  // Otherwise SpaceBeg=kSpaceBeg (fixed address).
  // kSpaceSize is a power of two.
  // At the beginning the entire space is mprotect-ed, then small parts of it
@@ -69,25 +69,45 @@ class SizeClassAllocator64 {
      return base + (static_cast<uptr>(ptr32) << kCompactPtrScale);
    }
  
-  void Init(s32 release_to_os_interval_ms) {
+  // If heap_start is nonzero, assumes kSpaceSize bytes are already mapped R/W
+  // at heap_start and places the heap there.  This mode requires kSpaceBeg ==
+  // ~(uptr)0.
+  void Init(s32 release_to_os_interval_ms, uptr heap_start = 0) {
      uptr TotalSpaceSize = kSpaceSize + AdditionalSize();
-    if (kUsingConstantSpaceBeg) {
-      CHECK(IsAligned(kSpaceBeg, SizeClassMap::kMaxSize));
-      CHECK_EQ(kSpaceBeg, address_range.Init(TotalSpaceSize,
-                                             PrimaryAllocatorName, kSpaceBeg));
+    PremappedHeap = heap_start != 0;
+    if (PremappedHeap) {
+      CHECK(!kUsingConstantSpaceBeg);
+      NonConstSpaceBeg = heap_start;
+      uptr RegionInfoSize = AdditionalSize();
+      RegionInfoSpace =
+          address_range.Init(RegionInfoSize, PrimaryAllocatorName);
+      CHECK_NE(RegionInfoSpace, ~(uptr)0);
+      CHECK_EQ(RegionInfoSpace,
+               address_range.MapOrDie(RegionInfoSpace, RegionInfoSize,
+                                      "SizeClassAllocator: region info"));
+      MapUnmapCallback().OnMap(RegionInfoSpace, RegionInfoSize);
      } else {
-      // Combined allocator expects that an 2^N allocation is always aligned to
-      // 2^N. For this to work, the start of the space needs to be aligned as
-      // high as the largest size class (which also needs to be a power of 2).
-      NonConstSpaceBeg = address_range.InitAligned(
-          TotalSpaceSize, SizeClassMap::kMaxSize, PrimaryAllocatorName);
-      CHECK_NE(NonConstSpaceBeg, ~(uptr)0);
+      if (kUsingConstantSpaceBeg) {
+        CHECK(IsAligned(kSpaceBeg, SizeClassMap::kMaxSize));
+        CHECK_EQ(kSpaceBeg,
+                 address_range.Init(TotalSpaceSize, PrimaryAllocatorName,
+                                    kSpaceBeg));
+      } else {
+        // Combined allocator expects that an 2^N allocation is always aligned
+        // to 2^N. For this to work, the start of the space needs to be aligned
+        // as high as the largest size class (which also needs to be a power of
+        // 2).
+        NonConstSpaceBeg = address_range.InitAligned(
+            TotalSpaceSize, SizeClassMap::kMaxSize, PrimaryAllocatorName);
+        CHECK_NE(NonConstSpaceBeg, ~(uptr)0);
+      }
+      RegionInfoSpace = SpaceEnd();
+      MapWithCallbackOrDie(RegionInfoSpace, AdditionalSize(),
+                           "SizeClassAllocator: region info");
      }
      SetReleaseToOSIntervalMs(release_to_os_interval_ms);
-    MapWithCallbackOrDie(SpaceEnd(), AdditionalSize(),
-                         "SizeClassAllocator: region info");
      // Check that the RegionInfo array is aligned on the CacheLine size.
-    DCHECK_EQ(SpaceEnd() % kCacheLineSize, 0);
+    DCHECK_EQ(RegionInfoSpace % kCacheLineSize, 0);
    }
  
    s32 ReleaseToOSIntervalMs() const {
@@ -144,6 +164,17 @@ class SizeClassAllocator64 {
      CompactPtrT *free_array = GetFreeArray(region_beg);
  
      BlockingMutexLock l(&region->mutex);
+#if SANITIZER_WINDOWS
+    /* On Windows unmapping of memory during __sanitizer_purge_allocator is
+    explicit and immediate, so unmapped regions must be explicitly mapped back
+    in when they are accessed again. */
+    if (region->rtoi.last_released_bytes > 0) {
+      MmapFixedOrDie(region_beg, region->mapped_user,
+                                      "SizeClassAllocator: region data");
+      region->rtoi.n_freed_at_last_release = 0;
+      region->rtoi.last_released_bytes = 0;
+    }
+#endif
      if (UNLIKELY(region->num_freed_chunks < n_chunks)) {
        if (UNLIKELY(!PopulateFreeArray(stat, class_id, region,
                                        n_chunks - region->num_freed_chunks)))
@@ -360,8 +391,7 @@ class SizeClassAllocator64 {
      }
      ~PackedCounterArray() {
        if (buffer) {
-        memory_mapper->UnmapPackedCounterArrayBuffer(
-            reinterpret_cast<uptr>(buffer), buffer_size);
+        memory_mapper->UnmapPackedCounterArrayBuffer(buffer, buffer_size);
        }
      }
  
@@ -586,6 +616,11 @@ class SizeClassAllocator64 {
  
    atomic_sint32_t release_to_os_interval_ms_;
  
+  uptr RegionInfoSpace;
+
+  // True if the user has already mapped the entire heap R/W.
+  bool PremappedHeap;
+
    struct Stats {
      uptr n_allocated;
      uptr n_freed;
@@ -615,7 +650,7 @@ class SizeClassAllocator64 {
  
    RegionInfo *GetRegionInfo(uptr class_id) const {
      DCHECK_LT(class_id, kNumClasses);
-    RegionInfo *regions = reinterpret_cast<RegionInfo *>(SpaceEnd());
+    RegionInfo *regions = reinterpret_cast<RegionInfo *>(RegionInfoSpace);
      return &regions[class_id];
    }
  
@@ -640,6 +675,9 @@ class SizeClassAllocator64 {
    }
  
    bool MapWithCallback(uptr beg, uptr size, const char *name) {
+    if (PremappedHeap)
+      return beg >= NonConstSpaceBeg &&
+             beg + size <= NonConstSpaceBeg + kSpaceSize;
      uptr mapped = address_range.Map(beg, size, name);
      if (UNLIKELY(!mapped))
        return false;
@@ -649,11 +687,18 @@ class SizeClassAllocator64 {
    }
  
    void MapWithCallbackOrDie(uptr beg, uptr size, const char *name) {
+    if (PremappedHeap) {
+      CHECK_GE(beg, NonConstSpaceBeg);
+      CHECK_LE(beg + size, NonConstSpaceBeg + kSpaceSize);
+      return;
+    }
      CHECK_EQ(beg, address_range.MapOrDie(beg, size, name));
      MapUnmapCallback().OnMap(beg, size);
    }
  
    void UnmapWithCallbackOrDie(uptr beg, uptr size) {
+    if (PremappedHeap)
+      return;
      MapUnmapCallback().OnUnmap(beg, size);
      address_range.Unmap(beg, size);
    }
@@ -792,17 +837,16 @@ class SizeClassAllocator64 {
        return released_bytes;
      }
  
-    uptr MapPackedCounterArrayBuffer(uptr buffer_size) {
+    void *MapPackedCounterArrayBuffer(uptr buffer_size) {
        // TODO(alekseyshl): The idea to explore is to check if we have enough
        // space between num_freed_chunks*sizeof(CompactPtrT) and
        // mapped_free_array to fit buffer_size bytes and use that space instead
        // of mapping a temporary one.
-      return reinterpret_cast<uptr>(
-          MmapOrDieOnFatalError(buffer_size, "ReleaseToOSPageCounters"));
+      return MmapOrDieOnFatalError(buffer_size, "ReleaseToOSPageCounters");
      }
  
-    void UnmapPackedCounterArrayBuffer(uptr buffer, uptr buffer_size) {
-      UnmapOrDie(reinterpret_cast<void *>(buffer), buffer_size);
+    void UnmapPackedCounterArrayBuffer(void *buffer, uptr buffer_size) {
+      UnmapOrDie(buffer, buffer_size);
      }
  
      // Releases [from, to) range of pages back to OS.
@@ -823,6 +867,9 @@ class SizeClassAllocator64 {
  
    // Attempts to release RAM occupied by freed chunks back to OS. The region is
    // expected to be locked.
+  //
+  // TODO(morehouse): Support a callback on memory release so HWASan can release
+  // aliases as well.
    void MaybeReleaseToOS(uptr class_id, bool force) {
      RegionInfo *region = GetRegionInfo(class_id);
      const uptr chunk_size = ClassIdToSize(class_id);
diff --git a/libsanitizer/sanitizer_common/sanitizer_allocator_size_class_map.h b/libsanitizer/sanitizer_common/sanitizer_allocator_size_class_map.h
index 12d8c892307..c50d13303ed 100644
--- a/libsanitizer/sanitizer_common/sanitizer_allocator_size_class_map.h
+++ b/libsanitizer/sanitizer_common/sanitizer_allocator_size_class_map.h
@@ -24,7 +24,7 @@
  //             E.g. with kNumBits==3 all size classes after 2^kMidSizeLog
  //             look like 0b1xx0..0, where x is either 0 or 1.
  //
-// Example: kNumBits=3, kMidSizeLog=4, kMidSizeLog=8, kMaxSizeLog=17:
+// Example: kNumBits=3, kMinSizeLog=4, kMidSizeLog=8, kMaxSizeLog=17:
  //
  // Classes 1 - 16 correspond to sizes 16 to 256 (size = class_id * 16).
  // Next 4 classes: 256 + i * 64  (i = 1 to 4).
diff --git a/libsanitizer/sanitizer_common/sanitizer_atomic_clang_mips.h b/libsanitizer/sanitizer_common/sanitizer_atomic_clang_mips.h
index 59155e9883e..2b39097112d 100644
--- a/libsanitizer/sanitizer_common/sanitizer_atomic_clang_mips.h
+++ b/libsanitizer/sanitizer_common/sanitizer_atomic_clang_mips.h
@@ -41,7 +41,7 @@ inline atomic_uint64_t::Type atomic_fetch_add(volatile atomic_uint64_t *ptr,
                                                atomic_uint64_t::Type val,
                                                memory_order mo) {
    DCHECK(mo &
-         (memory_order_relaxed | memory_order_releasae | memory_order_seq_cst));
+         (memory_order_relaxed | memory_order_release | memory_order_seq_cst));
    DCHECK(!((uptr)ptr % sizeof(*ptr)));
  
    atomic_uint64_t::Type ret;
@@ -67,7 +67,7 @@ inline bool atomic_compare_exchange_strong(volatile atomic_uint64_t *ptr,
                                             atomic_uint64_t::Type xchg,
                                             memory_order mo) {
    DCHECK(mo &
-         (memory_order_relaxed | memory_order_releasae | memory_order_seq_cst));
+         (memory_order_relaxed | memory_order_release | memory_order_seq_cst));
    DCHECK(!((uptr)ptr % sizeof(*ptr)));
  
    typedef atomic_uint64_t::Type Type;
@@ -90,7 +90,7 @@ template <>
  inline atomic_uint64_t::Type atomic_load(const volatile atomic_uint64_t *ptr,
                                           memory_order mo) {
    DCHECK(mo &
-         (memory_order_relaxed | memory_order_releasae | memory_order_seq_cst));
+         (memory_order_relaxed | memory_order_release | memory_order_seq_cst));
    DCHECK(!((uptr)ptr % sizeof(*ptr)));
  
    atomic_uint64_t::Type zero = 0;
@@ -103,7 +103,7 @@ template <>
  inline void atomic_store(volatile atomic_uint64_t *ptr, atomic_uint64_t::Type v,
                           memory_order mo) {
    DCHECK(mo &
-         (memory_order_relaxed | memory_order_releasae | memory_order_seq_cst));
+         (memory_order_relaxed | memory_order_release | memory_order_seq_cst));
    DCHECK(!((uptr)ptr % sizeof(*ptr)));
  
    __spin_lock(&lock.lock);
diff --git a/libsanitizer/sanitizer_common/sanitizer_chained_origin_depot.cpp b/libsanitizer/sanitizer_common/sanitizer_chained_origin_depot.cpp
new file mode 100644
index 00000000000..250ac39e130
--- /dev/null
+++ b/libsanitizer/sanitizer_common/sanitizer_chained_origin_depot.cpp
@@ -0,0 +1,108 @@
+//===-- sanitizer_chained_origin_depot.cpp --------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// A storage for chained origins.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_chained_origin_depot.h"
+
+namespace __sanitizer {
+
+bool ChainedOriginDepot::ChainedOriginDepotNode::eq(
+    u32 hash, const args_type &args) const {
+  return here_id == args.here_id && prev_id == args.prev_id;
+}
+
+uptr ChainedOriginDepot::ChainedOriginDepotNode::storage_size(
+    const args_type &args) {
+  return sizeof(ChainedOriginDepotNode);
+}
+
+/* This is murmur2 hash for the 64->32 bit case.
+   It does not behave all that well because the keys have a very biased
+   distribution (I've seen 7-element buckets with the table only 14% full).
+
+   here_id is built of
+   * (1 bits) Reserved, zero.
+   * (8 bits) Part id = bits 13..20 of the hash value of here_id's key.
+   * (23 bits) Sequential number (each part has each own sequence).
+
+   prev_id has either the same distribution as here_id (but with 3:8:21)
+   split, or one of two reserved values (-1) or (-2). Either case can
+   dominate depending on the workload.
+*/
+u32 ChainedOriginDepot::ChainedOriginDepotNode::hash(const args_type &args) {
+  const u32 m = 0x5bd1e995;
+  const u32 seed = 0x9747b28c;
+  const u32 r = 24;
+  u32 h = seed;
+  u32 k = args.here_id;
+  k *= m;
+  k ^= k >> r;
+  k *= m;
+  h *= m;
+  h ^= k;
+
+  k = args.prev_id;
+  k *= m;
+  k ^= k >> r;
+  k *= m;
+  h *= m;
+  h ^= k;
+
+  h ^= h >> 13;
+  h *= m;
+  h ^= h >> 15;
+  return h;
+}
+
+bool ChainedOriginDepot::ChainedOriginDepotNode::is_valid(
+    const args_type &args) {
+  return true;
+}
+
+void ChainedOriginDepot::ChainedOriginDepotNode::store(const args_type &args,
+                                                       u32 other_hash) {
+  here_id = args.here_id;
+  prev_id = args.prev_id;
+}
+
+ChainedOriginDepot::ChainedOriginDepotNode::args_type
+ChainedOriginDepot::ChainedOriginDepotNode::load() const {
+  args_type ret = {here_id, prev_id};
+  return ret;
+}
+
+ChainedOriginDepot::ChainedOriginDepotNode::Handle
+ChainedOriginDepot::ChainedOriginDepotNode::get_handle() {
+  return Handle(this);
+}
+
+ChainedOriginDepot::ChainedOriginDepot() {}
+
+StackDepotStats *ChainedOriginDepot::GetStats() { return depot.GetStats(); }
+
+bool ChainedOriginDepot::Put(u32 here_id, u32 prev_id, u32 *new_id) {
+  ChainedOriginDepotDesc desc = {here_id, prev_id};
+  bool inserted;
+  ChainedOriginDepotNode::Handle h = depot.Put(desc, &inserted);
+  *new_id = h.valid() ? h.id() : 0;
+  return inserted;
+}
+
+u32 ChainedOriginDepot::Get(u32 id, u32 *other) {
+  ChainedOriginDepotDesc desc = depot.Get(id);
+  *other = desc.prev_id;
+  return desc.here_id;
+}
+
+void ChainedOriginDepot::LockAll() { depot.LockAll(); }
+
+void ChainedOriginDepot::UnlockAll() { depot.UnlockAll(); }
+
+}  // namespace __sanitizer
diff --git a/libsanitizer/sanitizer_common/sanitizer_chained_origin_depot.h b/libsanitizer/sanitizer_common/sanitizer_chained_origin_depot.h
new file mode 100644
index 00000000000..453cdf6b544
--- /dev/null
+++ b/libsanitizer/sanitizer_common/sanitizer_chained_origin_depot.h
@@ -0,0 +1,88 @@
+//===-- sanitizer_chained_origin_depot.h ------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// A storage for chained origins.
+//===----------------------------------------------------------------------===//
+
+#ifndef SANITIZER_CHAINED_ORIGIN_DEPOT_H
+#define SANITIZER_CHAINED_ORIGIN_DEPOT_H
+
+#include "sanitizer_common.h"
+#include "sanitizer_stackdepotbase.h"
+
+namespace __sanitizer {
+
+class ChainedOriginDepot {
+ public:
+  ChainedOriginDepot();
+
+  // Gets the statistic of the origin chain storage.
+  StackDepotStats *GetStats();
+
+  // Stores a chain with StackDepot ID here_id and previous chain ID prev_id.
+  // If successful, returns true and the new chain id new_id.
+  // If the same element already exists, returns false and sets new_id to the
+  // existing ID.
+  bool Put(u32 here_id, u32 prev_id, u32 *new_id);
+
+  // Retrieves the stored StackDepot ID for the given origin ID.
+  u32 Get(u32 id, u32 *other);
+
+  void LockAll();
+  void UnlockAll();
+
+ private:
+  struct ChainedOriginDepotDesc {
+    u32 here_id;
+    u32 prev_id;
+  };
+
+  struct ChainedOriginDepotNode {
+    ChainedOriginDepotNode *link;
+    u32 id;
+    u32 here_id;
+    u32 prev_id;
+
+    typedef ChainedOriginDepotDesc args_type;
+
+    bool eq(u32 hash, const args_type &args) const;
+
+    static uptr storage_size(const args_type &args);
+
+    static u32 hash(const args_type &args);
+
+    static bool is_valid(const args_type &args);
+
+    void store(const args_type &args, u32 other_hash);
+
+    args_type load() const;
+
+    struct Handle {
+      ChainedOriginDepotNode *node_;
+      Handle() : node_(nullptr) {}
+      explicit Handle(ChainedOriginDepotNode *node) : node_(node) {}
+      bool valid() { return node_; }
+      u32 id() { return node_->id; }
+      int here_id() { return node_->here_id; }
+      int prev_id() { return node_->prev_id; }
+    };
+
+    Handle get_handle();
+
+    typedef Handle handle_type;
+  };
+
+  StackDepotBase<ChainedOriginDepotNode, 4, 20> depot;
+
+  ChainedOriginDepot(const ChainedOriginDepot &) = delete;
+  void operator=(const ChainedOriginDepot &) = delete;
+};
+
+}  // namespace __sanitizer
+
+#endif  // SANITIZER_CHAINED_ORIGIN_DEPOT_H
diff --git a/libsanitizer/sanitizer_common/sanitizer_common.cpp b/libsanitizer/sanitizer_common/sanitizer_common.cpp
index 87efda5bd37..33960d94a2f 100644
--- a/libsanitizer/sanitizer_common/sanitizer_common.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_common.cpp
@@ -87,7 +87,7 @@ const char *StripModuleName(const char *module) {
  void ReportErrorSummary(const char *error_message, const char *alt_tool_name) {
    if (!common_flags()->print_summary)
      return;
-  InternalScopedString buff(kMaxSummaryLength);
+  InternalScopedString buff;
    buff.append("SUMMARY: %s: %s",
                alt_tool_name ? alt_tool_name : SanitizerToolName, error_message);
    __sanitizer_report_error_summary(buff.data());
@@ -274,6 +274,14 @@ uptr ReadBinaryNameCached(/*out*/char *buf, uptr buf_len) {
    return name_len;
  }
  
+uptr ReadBinaryDir(/*out*/ char *buf, uptr buf_len) {
+  ReadBinaryNameCached(buf, buf_len);
+  const char *exec_name_pos = StripModuleName(buf);
+  uptr name_len = exec_name_pos - buf;
+  buf[name_len] = '\0';
+  return name_len;
+}
+
  #if !SANITIZER_GO
  void PrintCmdline() {
    char **argv = GetArgv();
diff --git a/libsanitizer/sanitizer_common/sanitizer_common.h b/libsanitizer/sanitizer_common/sanitizer_common.h
index bce24d68045..7b65dd7dfb8 100644
--- a/libsanitizer/sanitizer_common/sanitizer_common.h
+++ b/libsanitizer/sanitizer_common/sanitizer_common.h
@@ -44,7 +44,7 @@ const uptr kMaxPathLength = 4096;
  
  const uptr kMaxThreadStackSize = 1 << 30;  // 1Gb
  
-static const uptr kErrorMessageBufferSize = 1 << 16;
+const uptr kErrorMessageBufferSize = 1 << 16;
  
  // Denotes fake PC values that come from JIT/JAVA/etc.
  // For such PC values __tsan_symbolize_external_ex() will be called.
@@ -135,6 +135,15 @@ void UnmapFromTo(uptr from, uptr to);
  uptr MapDynamicShadow(uptr shadow_size_bytes, uptr shadow_scale,
                        uptr min_shadow_base_alignment, uptr &high_mem_end);
  
+// Let S = max(shadow_size, num_aliases * alias_size, ring_buffer_size).
+// Reserves 2*S bytes of address space to the right of the returned address and
+// ring_buffer_size bytes to the left.  The returned address is aligned to 2*S.
+// Also creates num_aliases regions of accessible memory starting at offset S
+// from the returned address.  Each region has size alias_size and is backed by
+// the same physical memory.
+uptr MapDynamicShadowAndAliases(uptr shadow_size, uptr alias_size,
+                                uptr num_aliases, uptr ring_buffer_size);
+
  // Reserve memory range [beg, end]. If madvise_shadow is true then apply
  // madvise (e.g. hugepages, core dumping) requested by options.
  void ReserveShadowMemoryRange(uptr beg, uptr end, const char *name,
@@ -248,6 +257,7 @@ const char *StripModuleName(const char *module);
  // OS
  uptr ReadBinaryName(/*out*/char *buf, uptr buf_len);
  uptr ReadBinaryNameCached(/*out*/char *buf, uptr buf_len);
+uptr ReadBinaryDir(/*out*/ char *buf, uptr buf_len);
  uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len);
  const char *GetProcessName();
  void UpdateProcessName();
@@ -294,8 +304,8 @@ void NORETURN ReportMmapFailureAndDie(uptr size, const char *mem_type,
                                        const char *mmap_type, error_t err,
                                        bool raw_report = false);
  
-// Specific tools may override behavior of "Die" and "CheckFailed" functions
-// to do tool-specific job.
+// Specific tools may override behavior of "Die" function to do tool-specific
+// job.
  typedef void (*DieCallbackType)(void);
  
  // It's possible to add several callbacks that would be run when "Die" is
@@ -307,9 +317,7 @@ bool RemoveDieCallback(DieCallbackType callback);
  
  void SetUserDieCallback(DieCallbackType callback);
  
-typedef void (*CheckFailedCallbackType)(const char *, int, const char *,
-                                       u64, u64);
-void SetCheckFailedCallback(CheckFailedCallbackType callback);
+void SetCheckUnwindCallback(void (*callback)());
  
  // Callback will be called if soft_rss_limit_mb is given and the limit is
  // exceeded (exceeded==true) or if rss went down below the limit
@@ -343,8 +351,6 @@ void ReportDeadlySignal(const SignalContext &sig, u32 tid,
  void SetAlternateSignalStack();
  void UnsetAlternateSignalStack();
  
-// We don't want a summary too long.
-const int kMaxSummaryLength = 1024;
  // Construct a one-line string:
  //   SUMMARY: SanitizerToolName: error_message
  // and pass it to __sanitizer_report_error_summary.
@@ -441,8 +447,14 @@ inline uptr Log2(uptr x) {
  
  // Don't use std::min, std::max or std::swap, to minimize dependency
  // on libstdc++.
-template<class T> T Min(T a, T b) { return a < b ? a : b; }
-template<class T> T Max(T a, T b) { return a > b ? a : b; }
+template <class T>
+constexpr T Min(T a, T b) {
+  return a < b ? a : b;
+}
+template <class T>
+constexpr T Max(T a, T b) {
+  return a > b ? a : b;
+}
  template<class T> void Swap(T& a, T& b) {
    T tmp = a;
    a = b;
@@ -467,6 +479,7 @@ inline int ToLower(int c) {
  template<typename T>
  class InternalMmapVectorNoCtor {
   public:
+  using value_type = T;
    void Initialize(uptr initial_capacity) {
      capacity_bytes_ = 0;
      size_ = 0;
@@ -590,21 +603,21 @@ class InternalMmapVector : public InternalMmapVectorNoCtor<T> {
    InternalMmapVector &operator=(InternalMmapVector &&) = delete;
  };
  
-class InternalScopedString : public InternalMmapVector<char> {
+class InternalScopedString {
   public:
-  explicit InternalScopedString(uptr max_length)
-      : InternalMmapVector<char>(max_length), length_(0) {
-    (*this)[0] = '\0';
-  }
-  uptr length() { return length_; }
+  InternalScopedString() : buffer_(1) { buffer_[0] = '\0'; }
+
+  uptr length() const { return buffer_.size() - 1; }
    void clear() {
-    (*this)[0] = '\0';
-    length_ = 0;
+    buffer_.resize(1);
+    buffer_[0] = '\0';
    }
    void append(const char *format, ...);
+  const char *data() const { return buffer_.data(); }
+  char *data() { return buffer_.data(); }
  
   private:
-  uptr length_;
+  InternalMmapVector<char> buffer_;
  };
  
  template <class T>
@@ -651,9 +664,13 @@ void Sort(T *v, uptr size, Compare comp = {}) {
  
  // Works like std::lower_bound: finds the first element that is not less
  // than the val.
-template <class Container, class Value, class Compare>
-uptr InternalLowerBound(const Container &v, uptr first, uptr last,
-                        const Value &val, Compare comp) {
+template <class Container,
+          class Compare = CompareLess<typename Container::value_type>>
+uptr InternalLowerBound(const Container &v,
+                        const typename Container::value_type &val,
+                        Compare comp = {}) {
+  uptr first = 0;
+  uptr last = v.size();
    while (last > first) {
      uptr mid = (first + last) / 2;
      if (comp(v[mid], val))
@@ -677,6 +694,27 @@ enum ModuleArch {
    kModuleArchRISCV64
  };
  
+// Sorts and removes duplicates from the container.
+template <class Container,
+          class Compare = CompareLess<typename Container::value_type>>
+void SortAndDedup(Container &v, Compare comp = {}) {
+  Sort(v.data(), v.size(), comp);
+  uptr size = v.size();
+  if (size < 2)
+    return;
+  uptr last = 0;
+  for (uptr i = 1; i < size; ++i) {
+    if (comp(v[last], v[i])) {
+      ++last;
+      if (last != i)
+        v[last] = v[i];
+    } else {
+      CHECK(!comp(v[i], v[last]));
+    }
+  }
+  v.resize(last + 1);
+}
+
  // Opens the file 'file_name" and reads up to 'max_len' bytes.
  // The resulting buffer is mmaped and stored in '*buff'.
  // Returns true if file was successfully opened and read.
diff --git a/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc b/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc
index 2f2787e283a..7867fccde39 100644
--- a/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc
+++ b/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc
@@ -239,7 +239,7 @@ extern const short *_tolower_tab_;
      COMMON_INTERCEPT_FUNCTION(fn)
  #endif
  
-#ifdef __GLIBC__
+#if SANITIZER_GLIBC
  // If we could not find the versioned symbol, fall back to an unversioned
  // lookup. This is needed to work around a GLibc bug that causes dlsym
  // with RTLD_NEXT to return the oldest versioned symbol.
@@ -2195,6 +2195,7 @@ INTERCEPTOR(int, clock_gettime, u32 clk_id, void *tp) {
    }
    return res;
  }
+#if SANITIZER_GLIBC
  namespace __sanitizer {
  extern "C" {
  int real_clock_gettime(u32 clk_id, void *tp) {
@@ -2204,6 +2205,7 @@ int real_clock_gettime(u32 clk_id, void *tp) {
  }
  }  // extern "C"
  }  // namespace __sanitizer
+#endif
  INTERCEPTOR(int, clock_settime, u32 clk_id, const void *tp) {
    void *ctx;
    COMMON_INTERCEPTOR_ENTER(ctx, clock_settime, clk_id, tp);
@@ -3355,7 +3357,7 @@ INTERCEPTOR(char *, setlocale, int category, char *locale) {
      COMMON_INTERCEPTOR_READ_RANGE(ctx, locale, REAL(strlen)(locale) + 1);
    char *res = REAL(setlocale)(category, locale);
    if (res) {
-    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, res, REAL(strlen)(res) + 1);
+    COMMON_INTERCEPTOR_INITIALIZE_RANGE(res, REAL(strlen)(res) + 1);
      unpoison_ctype_arrays(ctx);
    }
    return res;
@@ -4030,7 +4032,7 @@ INTERCEPTOR(int, sigwait, __sanitizer_sigset_t *set, int *sig) {
    // FIXME: under ASan the call below may write to freed memory and corrupt
    // its metadata. See
    // https://github.com/google/sanitizers/issues/321.
-  int res = REAL(sigwait)(set, sig);
+  int res = COMMON_INTERCEPTOR_BLOCK_REAL(sigwait)(set, sig);
    if (!res && sig) COMMON_INTERCEPTOR_WRITE_RANGE(ctx, sig, sizeof(*sig));
    return res;
  }
@@ -4047,7 +4049,7 @@ INTERCEPTOR(int, sigwaitinfo, __sanitizer_sigset_t *set, void *info) {
    // FIXME: under ASan the call below may write to freed memory and corrupt
    // its metadata. See
    // https://github.com/google/sanitizers/issues/321.
-  int res = REAL(sigwaitinfo)(set, info);
+  int res = COMMON_INTERCEPTOR_BLOCK_REAL(sigwaitinfo)(set, info);
    if (res > 0 && info) COMMON_INTERCEPTOR_WRITE_RANGE(ctx, info, siginfo_t_sz);
    return res;
  }
@@ -4066,7 +4068,7 @@ INTERCEPTOR(int, sigtimedwait, __sanitizer_sigset_t *set, void *info,
    // FIXME: under ASan the call below may write to freed memory and corrupt
    // its metadata. See
    // https://github.com/google/sanitizers/issues/321.
-  int res = REAL(sigtimedwait)(set, info, timeout);
+  int res = COMMON_INTERCEPTOR_BLOCK_REAL(sigtimedwait)(set, info, timeout);
    if (res > 0 && info) COMMON_INTERCEPTOR_WRITE_RANGE(ctx, info, siginfo_t_sz);
    return res;
  }
@@ -5995,6 +5997,9 @@ void unpoison_file(__sanitizer_FILE *fp) {
    if (fp->_IO_read_base && fp->_IO_read_base < fp->_IO_read_end)
      COMMON_INTERCEPTOR_INITIALIZE_RANGE(fp->_IO_read_base,
                                          fp->_IO_read_end - fp->_IO_read_base);
+  if (fp->_IO_write_base && fp->_IO_write_base < fp->_IO_write_end)
+    COMMON_INTERCEPTOR_INITIALIZE_RANGE(fp->_IO_write_base,
+                                        fp->_IO_write_end - fp->_IO_write_base);
  #endif
  #endif  // SANITIZER_HAS_STRUCT_FILE
  }
@@ -6221,6 +6226,8 @@ INTERCEPTOR(void, _obstack_newchunk, __sanitizer_obstack *obstack, int length) {
  INTERCEPTOR(int, fflush, __sanitizer_FILE *fp) {
    void *ctx;
    COMMON_INTERCEPTOR_ENTER(ctx, fflush, fp);
+  if (fp)
+    unpoison_file(fp);
    int res = REAL(fflush)(fp);
    // FIXME: handle fp == NULL
    if (fp) {
@@ -6240,6 +6247,8 @@ INTERCEPTOR(int, fclose, __sanitizer_FILE *fp) {
    COMMON_INTERCEPTOR_ENTER(ctx, fclose, fp);
    COMMON_INTERCEPTOR_FILE_CLOSE(ctx, fp);
    const FileMetadata *m = GetInterceptorMetadata(fp);
+  if (fp)
+    unpoison_file(fp);
    int res = REAL(fclose)(fp);
    if (m) {
      COMMON_INTERCEPTOR_INITIALIZE_RANGE(*m->addr, *m->size);
diff --git a/libsanitizer/sanitizer_common/sanitizer_common_interceptors_ioctl.inc b/libsanitizer/sanitizer_common/sanitizer_common_interceptors_ioctl.inc
index 490a04b2181..7f181258eab 100644
--- a/libsanitizer/sanitizer_common/sanitizer_common_interceptors_ioctl.inc
+++ b/libsanitizer/sanitizer_common/sanitizer_common_interceptors_ioctl.inc
@@ -330,13 +330,17 @@ static void ioctl_table_fill() {
    _(SOUND_PCM_WRITE_CHANNELS, WRITE, sizeof(int));
    _(SOUND_PCM_WRITE_FILTER, WRITE, sizeof(int));
    _(TCFLSH, NONE, 0);
+#if SANITIZER_GLIBC
    _(TCGETA, WRITE, struct_termio_sz);
+#endif
    _(TCGETS, WRITE, struct_termios_sz);
    _(TCSBRK, NONE, 0);
    _(TCSBRKP, NONE, 0);
+#if SANITIZER_GLIBC
    _(TCSETA, READ, struct_termio_sz);
    _(TCSETAF, READ, struct_termio_sz);
    _(TCSETAW, READ, struct_termio_sz);
+#endif
    _(TCSETS, READ, struct_termios_sz);
    _(TCSETSF, READ, struct_termios_sz);
    _(TCSETSW, READ, struct_termios_sz);
@@ -364,7 +368,7 @@ static void ioctl_table_fill() {
    _(VT_WAITACTIVE, NONE, 0);
  #endif
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
+#if SANITIZER_GLIBC
    // _(SIOCDEVPLIP, WRITE, struct_ifreq_sz); // the same as EQL_ENSLAVE
    _(CYGETDEFTHRESH, WRITE, sizeof(int));
    _(CYGETDEFTIMEOUT, WRITE, sizeof(int));
diff --git a/libsanitizer/sanitizer_common/sanitizer_common_interceptors_vfork_aarch64.inc.S b/libsanitizer/sanitizer_common/sanitizer_common_interceptors_vfork_aarch64.inc.S
index 20f42f1ea94..72e482754b6 100644
--- a/libsanitizer/sanitizer_common/sanitizer_common_interceptors_vfork_aarch64.inc.S
+++ b/libsanitizer/sanitizer_common/sanitizer_common_interceptors_vfork_aarch64.inc.S
@@ -1,6 +1,7 @@
  #if defined(__aarch64__) && defined(__linux__)
  
  #include "sanitizer_common/sanitizer_asm.h"
+#include "builtins/assembly.h"
  
  ASM_HIDDEN(COMMON_INTERCEPTOR_SPILL_AREA)
  
@@ -9,6 +10,7 @@ ASM_HIDDEN(COMMON_INTERCEPTOR_SPILL_AREA)
  ASM_TYPE_FUNCTION(ASM_WRAPPER_NAME(vfork))
  ASM_WRAPPER_NAME(vfork):
          // Save x30 in the off-stack spill area.
+        hint    #25 // paciasp
          stp     xzr, x30, [sp, #-16]!
          bl      COMMON_INTERCEPTOR_SPILL_AREA
          ldp     xzr, x30, [sp], 16
@@ -33,6 +35,7 @@ ASM_WRAPPER_NAME(vfork):
          bl     COMMON_INTERCEPTOR_SPILL_AREA
          ldr    x30, [x0]
          ldp    x0, xzr, [sp], 16
+        hint   #29 // autiasp
  
          ret
  ASM_SIZE(vfork)
@@ -40,4 +43,6 @@ ASM_SIZE(vfork)
  .weak vfork
  .set vfork, ASM_WRAPPER_NAME(vfork)
  
+GNU_PROPERTY_BTI_PAC
+
  #endif
diff --git a/libsanitizer/sanitizer_common/sanitizer_common_interface.inc b/libsanitizer/sanitizer_common/sanitizer_common_interface.inc
index c78b6e10b68..932e5478616 100644
--- a/libsanitizer/sanitizer_common/sanitizer_common_interface.inc
+++ b/libsanitizer/sanitizer_common/sanitizer_common_interface.inc
@@ -13,6 +13,7 @@ INTERFACE_FUNCTION(__sanitizer_contiguous_container_find_bad_address)
  INTERFACE_FUNCTION(__sanitizer_set_death_callback)
  INTERFACE_FUNCTION(__sanitizer_set_report_path)
  INTERFACE_FUNCTION(__sanitizer_set_report_fd)
+INTERFACE_FUNCTION(__sanitizer_get_report_path)
  INTERFACE_FUNCTION(__sanitizer_verify_contiguous_container)
  INTERFACE_WEAK_FUNCTION(__sanitizer_on_print)
  INTERFACE_WEAK_FUNCTION(__sanitizer_report_error_summary)
diff --git a/libsanitizer/sanitizer_common/sanitizer_common_libcdep.cpp b/libsanitizer/sanitizer_common/sanitizer_common_libcdep.cpp
index 047c5a17ea6..1037938f3d3 100644
--- a/libsanitizer/sanitizer_common/sanitizer_common_libcdep.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_common_libcdep.cpp
@@ -92,14 +92,13 @@ void *BackgroundThread(void *arg) {
  #endif
  
  void WriteToSyslog(const char *msg) {
-  InternalScopedString msg_copy(kErrorMessageBufferSize);
+  InternalScopedString msg_copy;
    msg_copy.append("%s", msg);
-  char *p = msg_copy.data();
-  char *q;
+  const char *p = msg_copy.data();
  
    // Print one line at a time.
    // syslog, at least on Android, has an implicit message length limit.
-  while ((q = internal_strchr(p, '\n'))) {
+  while (char* q = internal_strchr(p, '\n')) {
      *q = '\0';
      WriteOneLineToSyslog(p);
      p = q + 1;
diff --git a/libsanitizer/sanitizer_common/sanitizer_file.cpp b/libsanitizer/sanitizer_common/sanitizer_file.cpp
index 7cce60906b7..0b92dccde4a 100644
--- a/libsanitizer/sanitizer_common/sanitizer_file.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_file.cpp
@@ -58,6 +58,9 @@ void ReportFile::ReopenIfNecessary() {
    } else {
      internal_snprintf(full_path, kMaxPathLength, "%s.%zu", path_prefix, pid);
    }
+  if (common_flags()->log_suffix) {
+    internal_strlcat(full_path, common_flags()->log_suffix, kMaxPathLength);
+  }
    error_t err;
    fd = OpenFile(full_path, WrOnly, &err);
    if (fd == kInvalidFd) {
@@ -95,6 +98,12 @@ void ReportFile::SetReportPath(const char *path) {
    }
  }
  
+const char *ReportFile::GetReportPath() {
+  SpinMutexLock l(mu);
+  ReopenIfNecessary();
+  return full_path;
+}
+
  bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size,
                        uptr *read_len, uptr max_len, error_t *errno_p) {
    *buff = nullptr;
@@ -213,6 +222,10 @@ void __sanitizer_set_report_fd(void *fd) {
    report_file.fd = (fd_t)reinterpret_cast<uptr>(fd);
    report_file.fd_pid = internal_getpid();
  }
+
+const char *__sanitizer_get_report_path() {
+  return report_file.GetReportPath();
+}
  } // extern "C"
  
  #endif  // !SANITIZER_FUCHSIA
diff --git a/libsanitizer/sanitizer_common/sanitizer_file.h b/libsanitizer/sanitizer_common/sanitizer_file.h
index 26681f0493d..08671ab67d0 100644
--- a/libsanitizer/sanitizer_common/sanitizer_file.h
+++ b/libsanitizer/sanitizer_common/sanitizer_file.h
@@ -26,6 +26,7 @@ struct ReportFile {
    void Write(const char *buffer, uptr length);
    bool SupportsColors();
    void SetReportPath(const char *path);
+  const char *GetReportPath();
  
    // Don't use fields directly. They are only declared public to allow
    // aggregate initialization.
diff --git a/libsanitizer/sanitizer_common/sanitizer_flags.cpp b/libsanitizer/sanitizer_common/sanitizer_flags.cpp
index 21048be7304..d52e96a7c38 100644
--- a/libsanitizer/sanitizer_common/sanitizer_flags.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_flags.cpp
@@ -35,6 +35,7 @@ void CommonFlags::CopyFrom(const CommonFlags &other) {
  // Copy the string from "s" to "out", making the following substitutions:
  // %b = binary basename
  // %p = pid
+// %d = binary directory
  void SubstituteForFlagValue(const char *s, char *out, uptr out_size) {
    char *out_end = out + out_size;
    while (*s && out < out_end - 1) {
@@ -64,6 +65,12 @@ void SubstituteForFlagValue(const char *s, char *out, uptr out_size) {
          s += 2; // skip "%p"
          break;
        }
+      case 'd': {
+        uptr len = ReadBinaryDir(out, out_end - out);
+        out += len;
+        s += 2;  // skip "%d"
+        break;
+      }
        default:
          *out++ = *s++;
          break;
diff --git a/libsanitizer/sanitizer_common/sanitizer_flags.inc b/libsanitizer/sanitizer_common/sanitizer_flags.inc
index cfb5822645f..3bc44c6b1eb 100644
--- a/libsanitizer/sanitizer_common/sanitizer_flags.inc
+++ b/libsanitizer/sanitizer_common/sanitizer_flags.inc
@@ -59,6 +59,8 @@ COMMON_FLAG(
      bool, log_exe_name, false,
      "Mention name of executable when reporting error and "
      "append executable name to logs (as in \"log_path.exe_name.pid\").")
+COMMON_FLAG(const char *, log_suffix, nullptr,
+            "String to append to log file name, e.g. \".txt\".")
  COMMON_FLAG(
      bool, log_to_syslog, (bool)SANITIZER_ANDROID || (bool)SANITIZER_MAC,
      "Write all sanitizer output to syslog in addition to other means of "
diff --git a/libsanitizer/sanitizer_common/sanitizer_fuchsia.cpp b/libsanitizer/sanitizer_common/sanitizer_fuchsia.cpp
index 7200ffdac0f..4f692f99c20 100644
--- a/libsanitizer/sanitizer_common/sanitizer_fuchsia.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_fuchsia.cpp
@@ -14,7 +14,6 @@
  #include "sanitizer_fuchsia.h"
  #if SANITIZER_FUCHSIA
  
-#include <limits.h>
  #include <pthread.h>
  #include <stdlib.h>
  #include <unistd.h>
@@ -69,9 +68,7 @@ uptr internal_getpid() {
    return pid;
  }
  
-int internal_dlinfo(void *handle, int request, void *p) {
-  UNIMPLEMENTED();
-}
+int internal_dlinfo(void *handle, int request, void *p) { UNIMPLEMENTED(); }
  
  uptr GetThreadSelf() { return reinterpret_cast<uptr>(thrd_current()); }
  
@@ -153,9 +150,9 @@ void BlockingMutex::CheckLocked() {
    CHECK_NE(MtxUnlocked, atomic_load(m, memory_order_relaxed));
  }
  
-uptr GetPageSize() { return PAGE_SIZE; }
+uptr GetPageSize() { return _zx_system_get_page_size(); }
  
-uptr GetMmapGranularity() { return PAGE_SIZE; }
+uptr GetMmapGranularity() { return _zx_system_get_page_size(); }
  
  sanitizer_shadow_bounds_t ShadowBounds;
  
@@ -168,7 +165,7 @@ uptr GetMaxVirtualAddress() { return GetMaxUserVirtualAddress(); }
  
  static void *DoAnonymousMmapOrDie(uptr size, const char *mem_type,
                                    bool raw_report, bool die_for_nomem) {
-  size = RoundUpTo(size, PAGE_SIZE);
+  size = RoundUpTo(size, GetPageSize());
  
    zx_handle_t vmo;
    zx_status_t status = _zx_vmo_create(size, 0, &vmo);
@@ -214,15 +211,14 @@ void *MmapOrDieOnFatalError(uptr size, const char *mem_type) {
  
  uptr ReservedAddressRange::Init(uptr init_size, const char *name,
                                  uptr fixed_addr) {
-  init_size = RoundUpTo(init_size, PAGE_SIZE);
+  init_size = RoundUpTo(init_size, GetPageSize());
    DCHECK_EQ(os_handle_, ZX_HANDLE_INVALID);
    uintptr_t base;
    zx_handle_t vmar;
-  zx_status_t status =
-      _zx_vmar_allocate(
-          _zx_vmar_root_self(),
-          ZX_VM_CAN_MAP_READ | ZX_VM_CAN_MAP_WRITE | ZX_VM_CAN_MAP_SPECIFIC,
-          0, init_size, &vmar, &base);
+  zx_status_t status = _zx_vmar_allocate(
+      _zx_vmar_root_self(),
+      ZX_VM_CAN_MAP_READ | ZX_VM_CAN_MAP_WRITE | ZX_VM_CAN_MAP_SPECIFIC, 0,
+      init_size, &vmar, &base);
    if (status != ZX_OK)
      ReportMmapFailureAndDie(init_size, name, "zx_vmar_allocate", status);
    base_ = reinterpret_cast<void *>(base);
@@ -236,7 +232,7 @@ uptr ReservedAddressRange::Init(uptr init_size, const char *name,
  static uptr DoMmapFixedOrDie(zx_handle_t vmar, uptr fixed_addr, uptr map_size,
                               void *base, const char *name, bool die_for_nomem) {
    uptr offset = fixed_addr - reinterpret_cast<uptr>(base);
-  map_size = RoundUpTo(map_size, PAGE_SIZE);
+  map_size = RoundUpTo(map_size, GetPageSize());
    zx_handle_t vmo;
    zx_status_t status = _zx_vmo_create(map_size, 0, &vmo);
    if (status != ZX_OK) {
@@ -264,19 +260,19 @@ static uptr DoMmapFixedOrDie(zx_handle_t vmar, uptr fixed_addr, uptr map_size,
  
  uptr ReservedAddressRange::Map(uptr fixed_addr, uptr map_size,
                                 const char *name) {
-  return DoMmapFixedOrDie(os_handle_, fixed_addr, map_size, base_,
-                          name_, false);
+  return DoMmapFixedOrDie(os_handle_, fixed_addr, map_size, base_, name_,
+                          false);
  }
  
  uptr ReservedAddressRange::MapOrDie(uptr fixed_addr, uptr map_size,
                                      const char *name) {
-  return DoMmapFixedOrDie(os_handle_, fixed_addr, map_size, base_,
-                          name_, true);
+  return DoMmapFixedOrDie(os_handle_, fixed_addr, map_size, base_, name_, true);
  }
  
  void UnmapOrDieVmar(void *addr, uptr size, zx_handle_t target_vmar) {
-  if (!addr || !size) return;
-  size = RoundUpTo(size, PAGE_SIZE);
+  if (!addr || !size)
+    return;
+  size = RoundUpTo(size, GetPageSize());
  
    zx_status_t status =
        _zx_vmar_unmap(target_vmar, reinterpret_cast<uintptr_t>(addr), size);
@@ -316,7 +312,7 @@ void *MmapFixedNoAccess(uptr fixed_addr, uptr size, const char *name) {
  
  void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
                                     const char *mem_type) {
-  CHECK_GE(size, PAGE_SIZE);
+  CHECK_GE(size, GetPageSize());
    CHECK(IsPowerOfTwo(size));
    CHECK(IsPowerOfTwo(alignment));
  
@@ -356,7 +352,8 @@ void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
              _zx_vmar_root_self(),
              ZX_VM_PERM_READ | ZX_VM_PERM_WRITE | ZX_VM_SPECIFIC_OVERWRITE,
              addr - info.base, vmo, 0, size, &new_addr);
-        if (status == ZX_OK) CHECK_EQ(new_addr, addr);
+        if (status == ZX_OK)
+          CHECK_EQ(new_addr, addr);
        }
      }
      if (status == ZX_OK && addr != map_addr)
@@ -381,9 +378,18 @@ void UnmapOrDie(void *addr, uptr size) {
    UnmapOrDieVmar(addr, size, _zx_vmar_root_self());
  }
  
-// This is used on the shadow mapping, which cannot be changed.
-// Zircon doesn't have anything like MADV_DONTNEED.
-void ReleaseMemoryPagesToOS(uptr beg, uptr end) {}
+void ReleaseMemoryPagesToOS(uptr beg, uptr end) {
+  uptr beg_aligned = RoundUpTo(beg, GetPageSize());
+  uptr end_aligned = RoundDownTo(end, GetPageSize());
+  if (beg_aligned < end_aligned) {
+    zx_handle_t root_vmar = _zx_vmar_root_self();
+    CHECK_NE(root_vmar, ZX_HANDLE_INVALID);
+    zx_status_t status =
+        _zx_vmar_op_range(root_vmar, ZX_VMAR_OP_DECOMMIT, beg_aligned,
+                          end_aligned - beg_aligned, nullptr, 0);
+    CHECK_EQ(status, ZX_OK);
+  }
+}
  
  void DumpProcessMap() {
    // TODO(mcgrathr): write it
@@ -412,8 +418,9 @@ bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size,
      uint64_t vmo_size;
      status = _zx_vmo_get_size(vmo, &vmo_size);
      if (status == ZX_OK) {
-      if (vmo_size < max_len) max_len = vmo_size;
-      size_t map_size = RoundUpTo(max_len, PAGE_SIZE);
+      if (vmo_size < max_len)
+        max_len = vmo_size;
+      size_t map_size = RoundUpTo(max_len, GetPageSize());
        uintptr_t addr;
        status = _zx_vmar_map(_zx_vmar_root_self(), ZX_VM_PERM_READ, 0, vmo, 0,
                              map_size, &addr);
@@ -425,7 +432,8 @@ bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size,
      }
      _zx_handle_close(vmo);
    }
-  if (status != ZX_OK && errno_p) *errno_p = status;
+  if (status != ZX_OK && errno_p)
+    *errno_p = status;
    return status == ZX_OK;
  }
  
@@ -499,9 +507,7 @@ bool GetRandom(void *buffer, uptr length, bool blocking) {
    return true;
  }
  
-u32 GetNumberOfCPUs() {
-  return zx_system_get_num_cpus();
-}
+u32 GetNumberOfCPUs() { return zx_system_get_num_cpus(); }
  
  uptr GetRSS() { UNIMPLEMENTED(); }
  
@@ -529,6 +535,10 @@ void __sanitizer_set_report_path(const char *path) {
  void __sanitizer_set_report_fd(void *fd) {
    UNREACHABLE("not available on Fuchsia");
  }
+
+const char *__sanitizer_get_report_path() {
+  UNREACHABLE("not available on Fuchsia");
+}
  }  // extern "C"
  
  #endif  // SANITIZER_FUCHSIA
diff --git a/libsanitizer/sanitizer_common/sanitizer_interface_internal.h b/libsanitizer/sanitizer_common/sanitizer_interface_internal.h
index be8023e9e16..0b001c1c483 100644
--- a/libsanitizer/sanitizer_common/sanitizer_interface_internal.h
+++ b/libsanitizer/sanitizer_common/sanitizer_interface_internal.h
@@ -28,6 +28,10 @@ extern "C" {
    // (casted to void *).
    SANITIZER_INTERFACE_ATTRIBUTE
    void __sanitizer_set_report_fd(void *fd);
+  // Get the current full report file path, if a path was specified by
+  // an earlier call to __sanitizer_set_report_path. Returns null otherwise.
+  SANITIZER_INTERFACE_ATTRIBUTE
+  const char *__sanitizer_get_report_path();
  
    typedef struct {
        int coverage_sandboxed;
diff --git a/libsanitizer/sanitizer_common/sanitizer_internal_defs.h b/libsanitizer/sanitizer_common/sanitizer_internal_defs.h
index d8f0540037d..84053fec264 100644
--- a/libsanitizer/sanitizer_common/sanitizer_internal_defs.h
+++ b/libsanitizer/sanitizer_common/sanitizer_internal_defs.h
@@ -409,6 +409,9 @@ inline void Trap() {
      (void)enable_fp;                      \
    } while (0)
  
+constexpr u32 kInvalidTid = -1;
+constexpr u32 kMainTid = 0;
+
  }  // namespace __sanitizer
  
  namespace __asan {
diff --git a/libsanitizer/sanitizer_common/sanitizer_libignore.cpp b/libsanitizer/sanitizer_common/sanitizer_libignore.cpp
index 9ea19bc21fa..a65d3d896e3 100644
--- a/libsanitizer/sanitizer_common/sanitizer_libignore.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_libignore.cpp
@@ -38,7 +38,7 @@ void LibIgnore::AddIgnoredLibrary(const char *name_templ) {
  void LibIgnore::OnLibraryLoaded(const char *name) {
    BlockingMutexLock lock(&mutex_);
    // Try to match suppressions with symlink target.
-  InternalScopedString buf(kMaxPathLength);
+  InternalMmapVector<char> buf(kMaxPathLength);
    if (name && internal_readlink(name, buf.data(), buf.size() - 1) > 0 &&
        buf[0]) {
      for (uptr i = 0; i < count_; i++) {
diff --git a/libsanitizer/sanitizer_common/sanitizer_linux.cpp b/libsanitizer/sanitizer_common/sanitizer_linux.cpp
index 379f6d9e294..b371477755f 100644
--- a/libsanitizer/sanitizer_common/sanitizer_linux.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_linux.cpp
@@ -183,6 +183,14 @@ uptr internal_munmap(void *addr, uptr length) {
    return internal_syscall(SYSCALL(munmap), (uptr)addr, length);
  }
  
+#if SANITIZER_LINUX
+uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags,
+                     void *new_address) {
+  return internal_syscall(SYSCALL(mremap), (uptr)old_address, old_size,
+                          new_size, flags, (uptr)new_address);
+}
+#endif
+
  int internal_mprotect(void *addr, uptr length, int prot) {
    return internal_syscall(SYSCALL(mprotect), (uptr)addr, length, prot);
  }
@@ -489,22 +497,24 @@ int TgKill(pid_t pid, tid_t tid, int sig) {
  }
  #endif
  
-#if !SANITIZER_SOLARIS && !SANITIZER_NETBSD
+#if SANITIZER_GLIBC
  u64 NanoTime() {
-#if SANITIZER_FREEBSD
-  timeval tv;
-#else
    kernel_timeval tv;
-#endif
    internal_memset(&tv, 0, sizeof(tv));
    internal_syscall(SYSCALL(gettimeofday), &tv, 0);
-  return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000;
+  return (u64)tv.tv_sec * 1000 * 1000 * 1000 + tv.tv_usec * 1000;
  }
-
+// Used by real_clock_gettime.
  uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp) {
    return internal_syscall(SYSCALL(clock_gettime), clk_id, tp);
  }
-#endif  // !SANITIZER_SOLARIS && !SANITIZER_NETBSD
+#elif !SANITIZER_SOLARIS && !SANITIZER_NETBSD
+u64 NanoTime() {
+  struct timespec ts;
+  clock_gettime(CLOCK_REALTIME, &ts);
+  return (u64)ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec;
+}
+#endif
  
  // Like getenv, but reads env directly from /proc (on Linux) or parses the
  // 'environ' array (on some others) and does not use libc. This function
@@ -1334,50 +1344,42 @@ uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
  #elif SANITIZER_RISCV64
  uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
                      int *parent_tidptr, void *newtls, int *child_tidptr) {
-  long long res;
    if (!fn || !child_stack)
      return -EINVAL;
+
    CHECK_EQ(0, (uptr)child_stack % 16);
-  child_stack = (char *)child_stack - 2 * sizeof(unsigned long long);
-  ((unsigned long long *)child_stack)[0] = (uptr)fn;
-  ((unsigned long long *)child_stack)[1] = (uptr)arg;
  
-  register int (*__fn)(void *) __asm__("a0") = fn;
+  register int res __asm__("a0");
+  register int __flags __asm__("a0") = flags;
    register void *__stack __asm__("a1") = child_stack;
-  register int __flags __asm__("a2") = flags;
-  register void *__arg __asm__("a3") = arg;
-  register int *__ptid __asm__("a4") = parent_tidptr;
-  register void *__tls __asm__("a5") = newtls;
-  register int *__ctid __asm__("a6") = child_tidptr;
+  register int *__ptid __asm__("a2") = parent_tidptr;
+  register void *__tls __asm__("a3") = newtls;
+  register int *__ctid __asm__("a4") = child_tidptr;
+  register int (*__fn)(void *) __asm__("a5") = fn;
+  register void *__arg __asm__("a6") = arg;
+  register int nr_clone __asm__("a7") = __NR_clone;
  
    __asm__ __volatile__(
-      "mv a0,a2\n"          /* flags  */
-      "mv a2,a4\n"          /* ptid  */
-      "mv a3,a5\n"          /* tls  */
-      "mv a4,a6\n"          /* ctid  */
-      "addi a7, zero, %9\n" /* clone  */
-
        "ecall\n"
  
-      /* if (%r0 != 0)
-       *   return %r0;
+      /* if (a0 != 0)
+       *   return a0;
         */
        "bnez a0, 1f\n"
  
-      /* In the child, now. Call "fn(arg)". */
-      "ld  a0,  8(sp)\n"
-      "ld  a1, 16(sp)\n"
-      "jalr a1\n"
+      // In the child, now. Call "fn(arg)".
+      "mv a0, a6\n"
+      "jalr a5\n"
  
-      /* Call _exit(%r0).  */
-      "addi  a7, zero, %10\n"
+      // Call _exit(a0).
+      "addi a7, zero, %9\n"
        "ecall\n"
        "1:\n"
  
        : "=r"(res)
-      : "i"(-EINVAL), "r"(__fn), "r"(__stack), "r"(__flags), "r"(__arg),
-        "r"(__ptid), "r"(__tls), "r"(__ctid), "i"(__NR_clone), "i"(__NR_exit)
-      : "ra", "memory");
+      : "0"(__flags), "r"(__stack), "r"(__ptid), "r"(__tls), "r"(__ctid),
+        "r"(__fn), "r"(__arg), "r"(nr_clone), "i"(__NR_exit)
+      : "memory");
    return res;
  }
  #elif defined(__aarch64__)
diff --git a/libsanitizer/sanitizer_common/sanitizer_linux.h b/libsanitizer/sanitizer_common/sanitizer_linux.h
index 24902d1b6bc..9a23fcfb3b9 100644
--- a/libsanitizer/sanitizer_common/sanitizer_linux.h
+++ b/libsanitizer/sanitizer_common/sanitizer_linux.h
@@ -49,7 +49,9 @@ uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count);
  uptr internal_sigaltstack(const void* ss, void* oss);
  uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
      __sanitizer_sigset_t *oldset);
+#if SANITIZER_GLIBC
  uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp);
+#endif
  
  // Linux-only syscalls.
  #if SANITIZER_LINUX
@@ -96,7 +98,6 @@ class ThreadLister {
  // Exposed for testing.
  uptr ThreadDescriptorSize();
  uptr ThreadSelf();
-uptr ThreadSelfOffset();
  
  // Matches a library's file name against a base name (stripping path and version
  // information).
diff --git a/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp b/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp
index bc10e89b1ed..572aa86fa53 100644
--- a/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp
@@ -36,6 +36,7 @@
  #include <link.h>
  #include <pthread.h>
  #include <signal.h>
+#include <sys/mman.h>
  #include <sys/resource.h>
  #include <syslog.h>
  
@@ -48,6 +49,10 @@
  #include <osreldate.h>
  #include <sys/sysctl.h>
  #define pthread_getattr_np pthread_attr_get_np
+// The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before
+// that, it was never implemented. So just define it to zero.
+#undef MAP_NORESERVE
+#define MAP_NORESERVE 0
  #endif
  
  #if SANITIZER_NETBSD
@@ -183,85 +188,35 @@ __attribute__((unused)) static bool GetLibcVersion(int *major, int *minor,
  #endif
  }
  
-#if !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO && \
-    !SANITIZER_NETBSD && !SANITIZER_SOLARIS
-static uptr g_tls_size;
+// True if we can use dlpi_tls_data. glibc before 2.25 may leave NULL (BZ
+// #19826) so dlpi_tls_data cannot be used.
+//
+// musl before 1.2.3 and FreeBSD as of 12.2 incorrectly set dlpi_tls_data to
+// the TLS initialization image
+// https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=254774
+__attribute__((unused)) static int g_use_dlpi_tls_data;
  
-#ifdef __i386__
-#define CHECK_GET_TLS_STATIC_INFO_VERSION (!__GLIBC_PREREQ(2, 27))
-#else
-#define CHECK_GET_TLS_STATIC_INFO_VERSION 0
-#endif
+#if SANITIZER_GLIBC && !SANITIZER_GO
+__attribute__((unused)) static uptr g_tls_size;
+void InitTlsSize() {
+  int major, minor, patch;
+  g_use_dlpi_tls_data =
+      GetLibcVersion(&major, &minor, &patch) && major == 2 && minor >= 25;
  
-#if CHECK_GET_TLS_STATIC_INFO_VERSION
-#define DL_INTERNAL_FUNCTION __attribute__((regparm(3), stdcall))
-#else
-#define DL_INTERNAL_FUNCTION
+#if defined(__x86_64__) || defined(__powerpc64__)
+  void *get_tls_static_info = dlsym(RTLD_NEXT, "_dl_get_tls_static_info");
+  size_t tls_align;
+  ((void (*)(size_t *, size_t *))get_tls_static_info)(&g_tls_size, &tls_align);
  #endif
-
-namespace {
-struct GetTlsStaticInfoCall {
-  typedef void (*get_tls_func)(size_t*, size_t*);
-};
-struct GetTlsStaticInfoRegparmCall {
-  typedef void (*get_tls_func)(size_t*, size_t*) DL_INTERNAL_FUNCTION;
-};
-
-template <typename T>
-void CallGetTls(void* ptr, size_t* size, size_t* align) {
-  typename T::get_tls_func get_tls;
-  CHECK_EQ(sizeof(get_tls), sizeof(ptr));
-  internal_memcpy(&get_tls, &ptr, sizeof(ptr));
-  CHECK_NE(get_tls, 0);
-  get_tls(size, align);
-}
-
-bool CmpLibcVersion(int major, int minor, int patch) {
-  int ma;
-  int mi;
-  int pa;
-  if (!GetLibcVersion(&ma, &mi, &pa))
-    return false;
-  if (ma > major)
-    return true;
-  if (ma < major)
-    return false;
-  if (mi > minor)
-    return true;
-  if (mi < minor)
-    return false;
-  return pa >= patch;
-}
-
-}  // namespace
-
-void InitTlsSize() {
-  // all current supported platforms have 16 bytes stack alignment
-  const size_t kStackAlign = 16;
-  void *get_tls_static_info_ptr = dlsym(RTLD_NEXT, "_dl_get_tls_static_info");
-  size_t tls_size = 0;
-  size_t tls_align = 0;
-  // On i?86, _dl_get_tls_static_info used to be internal_function, i.e.
-  // __attribute__((regparm(3), stdcall)) before glibc 2.27 and is normal
-  // function in 2.27 and later.
-  if (CHECK_GET_TLS_STATIC_INFO_VERSION && !CmpLibcVersion(2, 27, 0))
-    CallGetTls<GetTlsStaticInfoRegparmCall>(get_tls_static_info_ptr,
-                                            &tls_size, &tls_align);
-  else
-    CallGetTls<GetTlsStaticInfoCall>(get_tls_static_info_ptr,
-                                     &tls_size, &tls_align);
-  if (tls_align < kStackAlign)
-    tls_align = kStackAlign;
-  g_tls_size = RoundUpTo(tls_size, tls_align);
  }
  #else
  void InitTlsSize() { }
-#endif
+#endif  // SANITIZER_GLIBC && !SANITIZER_GO
  
-#if (defined(__x86_64__) || defined(__i386__) || defined(__mips__) ||       \
-     defined(__aarch64__) || defined(__powerpc64__) || defined(__s390__) || \
-     defined(__arm__) || SANITIZER_RISCV64) &&                              \
-    SANITIZER_LINUX && !SANITIZER_ANDROID
+// On glibc x86_64, ThreadDescriptorSize() needs to be precise due to the usage
+// of g_tls_size. On other targets, ThreadDescriptorSize() is only used by lsan
+// to get the pointer to thread-specific data keys in the thread control block.
+#if (SANITIZER_FREEBSD || SANITIZER_LINUX) && !SANITIZER_ANDROID
  // sizeof(struct pthread) from glibc.
  static atomic_uintptr_t thread_descriptor_size;
  
@@ -294,9 +249,18 @@ uptr ThreadDescriptorSize() {
        val = FIRST_32_SECOND_64(1168, 2288);
      else if (minor <= 14)
        val = FIRST_32_SECOND_64(1168, 2304);
-    else
+    else if (minor < 32)  // Unknown version
        val = FIRST_32_SECOND_64(1216, 2304);
+    else  // minor == 32
+      val = FIRST_32_SECOND_64(1344, 2496);
    }
+#elif defined(__s390__) || defined(__sparc__)
+  // The size of a prefix of TCB including pthread::{specific_1stblock,specific}
+  // suffices. Just return offsetof(struct pthread, specific_used), which hasn't
+  // changed since 2007-05. Technically this applies to i386/x86_64 as well but
+  // we call _dl_get_tls_static_info and need the precise size of struct
+  // pthread.
+  return FIRST_32_SECOND_64(524, 1552);
  #elif defined(__mips__)
    // TODO(sagarthakur): add more values as per different glibc versions.
    val = FIRST_32_SECOND_64(1152, 1776);
@@ -320,21 +284,12 @@ uptr ThreadDescriptorSize() {
    val = 1776;
  #elif defined(__powerpc64__)
    val = 1776; // from glibc.ppc64le 2.20-8.fc21
-#elif defined(__s390__)
-  val = FIRST_32_SECOND_64(1152, 1776); // valid for glibc 2.22
  #endif
    if (val)
      atomic_store_relaxed(&thread_descriptor_size, val);
    return val;
  }
  
-// The offset at which pointer to self is located in the thread descriptor.
-const uptr kThreadSelfOffset = FIRST_32_SECOND_64(8, 16);
-
-uptr ThreadSelfOffset() {
-  return kThreadSelfOffset;
-}
-
  #if defined(__mips__) || defined(__powerpc64__) || SANITIZER_RISCV64
  // TlsPreTcbSize includes size of struct pthread_descr and size of tcb
  // head structure. It lies before the static tls blocks.
@@ -353,68 +308,74 @@ static uptr TlsPreTcbSize() {
  }
  #endif
  
-uptr ThreadSelf() {
-  uptr descr_addr;
-#if defined(__i386__)
-  asm("mov %%gs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset));
-#elif defined(__x86_64__)
-  asm("mov %%fs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset));
-#elif defined(__mips__)
-  // MIPS uses TLS variant I. The thread pointer (in hardware register $29)
-  // points to the end of the TCB + 0x7000. The pthread_descr structure is
-  // immediately in front of the TCB. TlsPreTcbSize() includes the size of the
-  // TCB and the size of pthread_descr.
-  const uptr kTlsTcbOffset = 0x7000;
-  uptr thread_pointer;
-  asm volatile(".set push;\
-                .set mips64r2;\
-                rdhwr %0,$29;\
-                .set pop" : "=r" (thread_pointer));
-  descr_addr = thread_pointer - kTlsTcbOffset - TlsPreTcbSize();
-#elif defined(__aarch64__) || defined(__arm__)
-  descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer()) -
-                                      ThreadDescriptorSize();
-#elif SANITIZER_RISCV64
-  // https://github.com/riscv/riscv-elf-psabi-doc/issues/53
-  uptr thread_pointer = reinterpret_cast<uptr>(__builtin_thread_pointer());
-  descr_addr = thread_pointer - TlsPreTcbSize();
-#elif defined(__s390__)
-  descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer());
-#elif defined(__powerpc64__)
-  // PPC64LE uses TLS variant I. The thread pointer (in GPR 13)
-  // points to the end of the TCB + 0x7000. The pthread_descr structure is
-  // immediately in front of the TCB. TlsPreTcbSize() includes the size of the
-  // TCB and the size of pthread_descr.
-  const uptr kTlsTcbOffset = 0x7000;
-  uptr thread_pointer;
-  asm("addi %0,13,%1" : "=r"(thread_pointer) : "I"(-kTlsTcbOffset));
-  descr_addr = thread_pointer - TlsPreTcbSize();
-#else
-#error "unsupported CPU arch"
-#endif
-  return descr_addr;
-}
-#endif  // (x86_64 || i386 || MIPS) && SANITIZER_LINUX
+#if !SANITIZER_GO
+namespace {
+struct TlsBlock {
+  uptr begin, end, align;
+  size_t tls_modid;
+  bool operator<(const TlsBlock &rhs) const { return begin < rhs.begin; }
+};
+}  // namespace
  
-#if SANITIZER_FREEBSD
-static void **ThreadSelfSegbase() {
-  void **segbase = 0;
-#if defined(__i386__)
-  // sysarch(I386_GET_GSBASE, segbase);
-  __asm __volatile("mov %%gs:0, %0" : "=r" (segbase));
-#elif defined(__x86_64__)
-  // sysarch(AMD64_GET_FSBASE, segbase);
-  __asm __volatile("movq %%fs:0, %0" : "=r" (segbase));
-#else
-#error "unsupported CPU arch"
+extern "C" void *__tls_get_addr(size_t *);
+
+static int CollectStaticTlsBlocks(struct dl_phdr_info *info, size_t size,
+                                  void *data) {
+  if (!info->dlpi_tls_modid)
+    return 0;
+  uptr begin = (uptr)info->dlpi_tls_data;
+#ifndef __s390__
+  if (!g_use_dlpi_tls_data) {
+    // Call __tls_get_addr as a fallback. This forces TLS allocation on glibc
+    // and FreeBSD.
+    size_t mod_and_off[2] = {info->dlpi_tls_modid, 0};
+    begin = (uptr)__tls_get_addr(mod_and_off);
+  }
  #endif
-  return segbase;
+  for (unsigned i = 0; i != info->dlpi_phnum; ++i)
+    if (info->dlpi_phdr[i].p_type == PT_TLS) {
+      static_cast<InternalMmapVector<TlsBlock> *>(data)->push_back(
+          TlsBlock{begin, begin + info->dlpi_phdr[i].p_memsz,
+                   info->dlpi_phdr[i].p_align, info->dlpi_tls_modid});
+      break;
+    }
+  return 0;
  }
  
-uptr ThreadSelf() {
-  return (uptr)ThreadSelfSegbase()[2];
-}
-#endif  // SANITIZER_FREEBSD
+__attribute__((unused)) static void GetStaticTlsBoundary(uptr *addr, uptr *size,
+                                                         uptr *align) {
+  InternalMmapVector<TlsBlock> ranges;
+  dl_iterate_phdr(CollectStaticTlsBlocks, &ranges);
+  uptr len = ranges.size();
+  Sort(ranges.begin(), len);
+  // Find the range with tls_modid=1. For glibc, because libc.so uses PT_TLS,
+  // this module is guaranteed to exist and is one of the initially loaded
+  // modules.
+  uptr one = 0;
+  while (one != len && ranges[one].tls_modid != 1) ++one;
+  if (one == len) {
+    // This may happen with musl if no module uses PT_TLS.
+    *addr = 0;
+    *size = 0;
+    *align = 1;
+    return;
+  }
+  // Find the maximum consecutive ranges. We consider two modules consecutive if
+  // the gap is smaller than the alignment. The dynamic loader places static TLS
+  // blocks this way not to waste space.
+  uptr l = one;
+  *align = ranges[l].align;
+  while (l != 0 && ranges[l].begin < ranges[l - 1].end + ranges[l - 1].align)
+    *align = Max(*align, ranges[--l].align);
+  uptr r = one + 1;
+  while (r != len && ranges[r].begin < ranges[r - 1].end + ranges[r - 1].align)
+    *align = Max(*align, ranges[r++].align);
+  *addr = ranges[l].begin;
+  *size = ranges[r - 1].end - ranges[l].begin;
+}
+#endif  // !SANITIZER_GO
+#endif  // (x86_64 || i386 || mips || ...) && (SANITIZER_FREEBSD ||
+        // SANITIZER_LINUX) && !SANITIZER_ANDROID
  
  #if SANITIZER_NETBSD
  static struct tls_tcb * ThreadSelfTlsTcb() {
@@ -465,33 +426,67 @@ static void GetTls(uptr *addr, uptr *size) {
      *addr = 0;
      *size = 0;
    }
-#elif SANITIZER_LINUX
-#if defined(__x86_64__) || defined(__i386__) || defined(__s390__)
-  *addr = ThreadSelf();
-  *size = GetTlsSize();
+#elif SANITIZER_GLIBC && defined(__x86_64__)
+  // For x86-64, use an O(1) approach which requires precise
+  // ThreadDescriptorSize. g_tls_size was initialized in InitTlsSize.
+  asm("mov %%fs:16,%0" : "=r"(*addr));
+  *size = g_tls_size;
    *addr -= *size;
    *addr += ThreadDescriptorSize();
-#elif defined(__mips__) || defined(__aarch64__) || defined(__powerpc64__) || \
-    defined(__arm__) || SANITIZER_RISCV64
-  *addr = ThreadSelf();
-  *size = GetTlsSize();
+#elif SANITIZER_GLIBC && defined(__powerpc64__)
+  // Workaround for glibc<2.25(?). 2.27 is known to not need this.
+  uptr tp;
+  asm("addi %0,13,-0x7000" : "=r"(tp));
+  const uptr pre_tcb_size = TlsPreTcbSize();
+  *addr = tp - pre_tcb_size;
+  *size = g_tls_size + pre_tcb_size;
+#elif SANITIZER_FREEBSD || SANITIZER_LINUX
+  uptr align;
+  GetStaticTlsBoundary(addr, size, &align);
+#if defined(__x86_64__) || defined(__i386__) || defined(__s390__) || \
+    defined(__sparc__)
+  if (SANITIZER_GLIBC) {
+#if defined(__x86_64__) || defined(__i386__)
+    align = Max<uptr>(align, 64);
  #else
-  *addr = 0;
-  *size = 0;
+    align = Max<uptr>(align, 16);
  #endif
-#elif SANITIZER_FREEBSD
-  void** segbase = ThreadSelfSegbase();
-  *addr = 0;
-  *size = 0;
-  if (segbase != 0) {
-    // tcbalign = 16
-    // tls_size = round(tls_static_space, tcbalign);
-    // dtv = segbase[1];
-    // dtv[2] = segbase - tls_static_space;
-    void **dtv = (void**) segbase[1];
-    *addr = (uptr) dtv[2];
-    *size = (*addr == 0) ? 0 : ((uptr) segbase[0] - (uptr) dtv[2]);
    }
+  const uptr tp = RoundUpTo(*addr + *size, align);
+
+  // lsan requires the range to additionally cover the static TLS surplus
+  // (elf/dl-tls.c defines 1664). Otherwise there may be false positives for
+  // allocations only referenced by tls in dynamically loaded modules.
+  if (SANITIZER_GLIBC)
+    *size += 1644;
+  else if (SANITIZER_FREEBSD)
+    *size += 128;  // RTLD_STATIC_TLS_EXTRA
+
+  // Extend the range to include the thread control block. On glibc, lsan needs
+  // the range to include pthread::{specific_1stblock,specific} so that
+  // allocations only referenced by pthread_setspecific can be scanned. This may
+  // underestimate by at most TLS_TCB_ALIGN-1 bytes but it should be fine
+  // because the number of bytes after pthread::specific is larger.
+  *addr = tp - RoundUpTo(*size, align);
+  *size = tp - *addr + ThreadDescriptorSize();
+#else
+  if (SANITIZER_GLIBC)
+    *size += 1664;
+  else if (SANITIZER_FREEBSD)
+    *size += 128;  // RTLD_STATIC_TLS_EXTRA
+#if defined(__mips__) || defined(__powerpc64__) || SANITIZER_RISCV64
+  const uptr pre_tcb_size = TlsPreTcbSize();
+  *addr -= pre_tcb_size;
+  *size += pre_tcb_size;
+#else
+  // arm and aarch64 reserve two words at TP, so this underestimates the range.
+  // However, this is sufficient for the purpose of finding the pointers to
+  // thread-specific data keys.
+  const uptr tcb_size = ThreadDescriptorSize();
+  *addr -= tcb_size;
+  *size += tcb_size;
+#endif
+#endif
  #elif SANITIZER_NETBSD
    struct tls_tcb * const tcb = ThreadSelfTlsTcb();
    *addr = 0;
@@ -518,15 +513,13 @@ static void GetTls(uptr *addr, uptr *size) {
  
  #if !SANITIZER_GO
  uptr GetTlsSize() {
-#if SANITIZER_FREEBSD || SANITIZER_ANDROID || SANITIZER_NETBSD || \
+#if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \
      SANITIZER_SOLARIS
    uptr addr, size;
    GetTls(&addr, &size);
    return size;
-#elif defined(__mips__) || defined(__powerpc64__) || SANITIZER_RISCV64
-  return RoundUpTo(g_tls_size + TlsPreTcbSize(), 16);
  #else
-  return g_tls_size;
+  return 0;
  #endif
  }
  #endif
@@ -547,10 +540,9 @@ void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
    if (!main) {
      // If stack and tls intersect, make them non-intersecting.
      if (*tls_addr > *stk_addr && *tls_addr < *stk_addr + *stk_size) {
-      CHECK_GT(*tls_addr + *tls_size, *stk_addr);
-      CHECK_LE(*tls_addr + *tls_size, *stk_addr + *stk_size);
-      *stk_size -= *tls_size;
-      *tls_addr = *stk_addr + *stk_size;
+      if (*stk_addr + *stk_size < *tls_addr + *tls_size)
+        *tls_size = *stk_addr + *stk_size - *tls_addr;
+      *stk_size = *tls_addr - *stk_addr;
      }
    }
  #endif
@@ -569,20 +561,12 @@ struct DlIteratePhdrData {
    bool first;
  };
  
-static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
-  DlIteratePhdrData *data = (DlIteratePhdrData*)arg;
-  InternalScopedString module_name(kMaxPathLength);
-  if (data->first) {
-    data->first = false;
-    // First module is the binary itself.
-    ReadBinaryNameCached(module_name.data(), module_name.size());
-  } else if (info->dlpi_name) {
-    module_name.append("%s", info->dlpi_name);
-  }
+static int AddModuleSegments(const char *module_name, dl_phdr_info *info,
+                             InternalMmapVectorNoCtor<LoadedModule> *modules) {
    if (module_name[0] == '\0')
      return 0;
    LoadedModule cur_module;
-  cur_module.set(module_name.data(), info->dlpi_addr);
+  cur_module.set(module_name, info->dlpi_addr);
    for (int i = 0; i < (int)info->dlpi_phnum; i++) {
      const Elf_Phdr *phdr = &info->dlpi_phdr[i];
      if (phdr->p_type == PT_LOAD) {
@@ -594,7 +578,26 @@ static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
                                   writable);
      }
    }
-  data->modules->push_back(cur_module);
+  modules->push_back(cur_module);
+  return 0;
+}
+
+static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
+  DlIteratePhdrData *data = (DlIteratePhdrData *)arg;
+  if (data->first) {
+    InternalMmapVector<char> module_name(kMaxPathLength);
+    data->first = false;
+    // First module is the binary itself.
+    ReadBinaryNameCached(module_name.data(), module_name.size());
+    return AddModuleSegments(module_name.data(), info, data->modules);
+  }
+
+  if (info->dlpi_name) {
+    InternalScopedString module_name;
+    module_name.append("%s", info->dlpi_name);
+    return AddModuleSegments(module_name.data(), info, data->modules);
+  }
+
    return 0;
  }
  
@@ -729,13 +732,9 @@ u32 GetNumberOfCPUs() {
  #elif SANITIZER_SOLARIS
    return sysconf(_SC_NPROCESSORS_ONLN);
  #else
-#if defined(CPU_COUNT)
    cpu_set_t CPUs;
    CHECK_EQ(sched_getaffinity(0, sizeof(cpu_set_t), &CPUs), 0);
    return CPU_COUNT(&CPUs);
-#else
-  return 1;
-#endif
  #endif
  }
  
@@ -802,20 +801,13 @@ void LogMessageOnPrintf(const char *str) {
  
  #endif  // SANITIZER_LINUX
  
-#if SANITIZER_LINUX && !SANITIZER_GO
+#if SANITIZER_GLIBC && !SANITIZER_GO
  // glibc crashes when using clock_gettime from a preinit_array function as the
  // vDSO function pointers haven't been initialized yet. __progname is
  // initialized after the vDSO function pointers, so if it exists, is not null
  // and is not empty, we can use clock_gettime.
  extern "C" SANITIZER_WEAK_ATTRIBUTE char *__progname;
-inline bool CanUseVDSO() {
-  // Bionic is safe, it checks for the vDSO function pointers to be initialized.
-  if (SANITIZER_ANDROID)
-    return true;
-  if (&__progname && __progname && *__progname)
-    return true;
-  return false;
-}
+inline bool CanUseVDSO() { return &__progname && __progname && *__progname; }
  
  // MonotonicNanoTime is a timing function that can leverage the vDSO by calling
  // clock_gettime. real_clock_gettime only exists if clock_gettime is
@@ -835,13 +827,13 @@ u64 MonotonicNanoTime() {
    return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
  }
  #else
-// Non-Linux & Go always use the syscall.
+// Non-glibc & Go always use the regular function.
  u64 MonotonicNanoTime() {
    timespec ts;
-  internal_clock_gettime(CLOCK_MONOTONIC, &ts);
+  clock_gettime(CLOCK_MONOTONIC, &ts);
    return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
  }
-#endif  // SANITIZER_LINUX && !SANITIZER_GO
+#endif  // SANITIZER_GLIBC && !SANITIZER_GO
  
  void ReExec() {
    const char *pathname = "/proc/self/exe";
@@ -910,6 +902,65 @@ uptr MapDynamicShadow(uptr shadow_size_bytes, uptr shadow_scale,
    return shadow_start;
  }
  
+static uptr MmapSharedNoReserve(uptr addr, uptr size) {
+  return internal_mmap(
+      reinterpret_cast<void *>(addr), size, PROT_READ | PROT_WRITE,
+      MAP_FIXED | MAP_SHARED | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
+}
+
+static uptr MremapCreateAlias(uptr base_addr, uptr alias_addr,
+                              uptr alias_size) {
+#if SANITIZER_LINUX
+  return internal_mremap(reinterpret_cast<void *>(base_addr), 0, alias_size,
+                         MREMAP_MAYMOVE | MREMAP_FIXED,
+                         reinterpret_cast<void *>(alias_addr));
+#else
+  CHECK(false && "mremap is not supported outside of Linux");
+  return 0;
+#endif
+}
+
+static void CreateAliases(uptr start_addr, uptr alias_size, uptr num_aliases) {
+  uptr total_size = alias_size * num_aliases;
+  uptr mapped = MmapSharedNoReserve(start_addr, total_size);
+  CHECK_EQ(mapped, start_addr);
+
+  for (uptr i = 1; i < num_aliases; ++i) {
+    uptr alias_addr = start_addr + i * alias_size;
+    CHECK_EQ(MremapCreateAlias(start_addr, alias_addr, alias_size), alias_addr);
+  }
+}
+
+uptr MapDynamicShadowAndAliases(uptr shadow_size, uptr alias_size,
+                                uptr num_aliases, uptr ring_buffer_size) {
+  CHECK_EQ(alias_size & (alias_size - 1), 0);
+  CHECK_EQ(num_aliases & (num_aliases - 1), 0);
+  CHECK_EQ(ring_buffer_size & (ring_buffer_size - 1), 0);
+
+  const uptr granularity = GetMmapGranularity();
+  shadow_size = RoundUpTo(shadow_size, granularity);
+  CHECK_EQ(shadow_size & (shadow_size - 1), 0);
+
+  const uptr alias_region_size = alias_size * num_aliases;
+  const uptr alignment =
+      2 * Max(Max(shadow_size, alias_region_size), ring_buffer_size);
+  const uptr left_padding = ring_buffer_size;
+
+  const uptr right_size = alignment;
+  const uptr map_size = left_padding + 2 * alignment;
+
+  const uptr map_start = reinterpret_cast<uptr>(MmapNoAccess(map_size));
+  CHECK_NE(map_start, static_cast<uptr>(-1));
+  const uptr right_start = RoundUpTo(map_start + left_padding, alignment);
+
+  UnmapFromTo(map_start, right_start - left_padding);
+  UnmapFromTo(right_start + right_size, map_start + map_size);
+
+  CreateAliases(right_start + right_size / 2, alias_size, num_aliases);
+
+  return right_start;
+}
+
  void InitializePlatformCommonFlags(CommonFlags *cf) {
  #if SANITIZER_ANDROID
    if (&__libc_get_static_tls_bounds == nullptr)
diff --git a/libsanitizer/sanitizer_common/sanitizer_local_address_space_view.h b/libsanitizer/sanitizer_common/sanitizer_local_address_space_view.h
index 5d1b5264b5e..0e19c4d4a80 100644
--- a/libsanitizer/sanitizer_common/sanitizer_local_address_space_view.h
+++ b/libsanitizer/sanitizer_common/sanitizer_local_address_space_view.h
@@ -7,7 +7,7 @@
  //===----------------------------------------------------------------------===//
  //
  // `LocalAddressSpaceView` provides the local (i.e. target and current address
-// space are the same) implementation of the `AddressSpaveView` interface which
+// space are the same) implementation of the `AddressSpaceView` interface which
  // provides a simple interface to load memory from another process (i.e.
  // out-of-process)
  //
diff --git a/libsanitizer/sanitizer_common/sanitizer_mac.cpp b/libsanitizer/sanitizer_common/sanitizer_mac.cpp
index 011ec6f4a0b..f4c6b442a14 100644
--- a/libsanitizer/sanitizer_common/sanitizer_mac.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_mac.cpp
@@ -37,13 +37,21 @@
  extern char **environ;
  #endif
  
-#if defined(__has_include) && __has_include(<os/trace.h>) && defined(__BLOCKS__)
+#if defined(__has_include) && __has_include(<os/trace.h>)
  #define SANITIZER_OS_TRACE 1
  #include <os/trace.h>
  #else
  #define SANITIZER_OS_TRACE 0
  #endif
  
+// import new crash reporting api
+#if defined(__has_include) && __has_include(<CrashReporterClient.h>)
+#define HAVE_CRASHREPORTERCLIENT_H 1
+#include <CrashReporterClient.h>
+#else
+#define HAVE_CRASHREPORTERCLIENT_H 0
+#endif
+
  #if !SANITIZER_IOS
  #include <crt_externs.h>  // for _NSGetArgv and _NSGetEnviron
  #else
@@ -62,6 +70,7 @@ extern "C" {
  #include <mach/mach_time.h>
  #include <mach/vm_statistics.h>
  #include <malloc/malloc.h>
+#include <os/log.h>
  #include <pthread.h>
  #include <sched.h>
  #include <signal.h>
@@ -133,6 +142,12 @@ uptr internal_munmap(void *addr, uptr length) {
    return munmap(addr, length);
  }
  
+uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags,
+                     void *new_address) {
+  CHECK(false && "internal_mremap is unimplemented on Mac");
+  return 0;
+}
+
  int internal_mprotect(void *addr, uptr length, int prot) {
    return mprotect(addr, length, prot);
  }
@@ -444,7 +459,7 @@ uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
    // On OS X the executable path is saved to the stack by dyld. Reading it
    // from there is much faster than calling dladdr, especially for large
    // binaries with symbols.
-  InternalScopedString exe_path(kMaxPathLength);
+  InternalMmapVector<char> exe_path(kMaxPathLength);
    uint32_t size = exe_path.size();
    if (_NSGetExecutablePath(exe_path.data(), &size) == 0 &&
        realpath(exe_path.data(), buf) != 0) {
@@ -620,6 +635,23 @@ constexpr u16 GetOSMajorKernelOffset() {
  
  using VersStr = char[64];
  
+static uptr ApproximateOSVersionViaKernelVersion(VersStr vers) {
+  u16 kernel_major = GetDarwinKernelVersion().major;
+  u16 offset = GetOSMajorKernelOffset();
+  CHECK_GE(kernel_major, offset);
+  u16 os_major = kernel_major - offset;
+
+  const char *format = "%d.0";
+  if (TARGET_OS_OSX) {
+    if (os_major >= 16) {  // macOS 11+
+      os_major -= 5;
+    } else {  // macOS 10.15 and below
+      format = "10.%d";
+    }
+  }
+  return internal_snprintf(vers, sizeof(VersStr), format, os_major);
+}
+
  static void GetOSVersion(VersStr vers) {
    uptr len = sizeof(VersStr);
    if (SANITIZER_IOSSIM) {
@@ -633,17 +665,19 @@ static void GetOSVersion(VersStr vers) {
    } else {
      int res =
          internal_sysctlbyname("kern.osproductversion", vers, &len, nullptr, 0);
-    if (res) {
-      // Fallback for XNU 17 (macOS 10.13) and below that do not provide the
-      // `kern.osproductversion` property.
-      u16 kernel_major = GetDarwinKernelVersion().major;
-      u16 offset = GetOSMajorKernelOffset();
-      CHECK_LE(kernel_major, 17);
-      CHECK_GE(kernel_major, offset);
-      u16 os_major = kernel_major - offset;
-
-      auto format = TARGET_OS_OSX ? "10.%d" : "%d.0";
-      len = internal_snprintf(vers, len, format, os_major);
+
+    // XNU 17 (macOS 10.13) and below do not provide the sysctl
+    // `kern.osproductversion` entry (res != 0).
+    bool no_os_version = res != 0;
+
+    // For launchd, sanitizer initialization runs before sysctl is setup
+    // (res == 0 && len != strlen(vers), vers is not a valid version).  However,
+    // the kernel version `kern.osrelease` is available.
+    bool launchd = (res == 0 && internal_strlen(vers) < 3);
+    if (launchd) CHECK_EQ(internal_getpid(), 1);
+
+    if (no_os_version || launchd) {
+      len = ApproximateOSVersionViaKernelVersion(vers);
      }
    }
    CHECK_LT(len, sizeof(VersStr));
@@ -681,7 +715,7 @@ static void MapToMacos(u16 *major, u16 *minor) {
  }
  
  static MacosVersion GetMacosAlignedVersionInternal() {
-  VersStr vers;
+  VersStr vers = {};
    GetOSVersion(vers);
  
    u16 major, minor;
@@ -707,7 +741,7 @@ MacosVersion GetMacosAlignedVersion() {
  }
  
  DarwinKernelVersion GetDarwinKernelVersion() {
-  VersStr vers;
+  VersStr vers = {};
    uptr len = sizeof(VersStr);
    int res = internal_sysctlbyname("kern.osrelease", vers, &len, nullptr, 0);
    CHECK_EQ(res, 0);
@@ -751,7 +785,51 @@ static BlockingMutex syslog_lock(LINKER_INITIALIZED);
  void WriteOneLineToSyslog(const char *s) {
  #if !SANITIZER_GO
    syslog_lock.CheckLocked();
-  asl_log(nullptr, nullptr, ASL_LEVEL_ERR, "%s", s);
+  if (GetMacosAlignedVersion() >= MacosVersion(10, 12)) {
+    os_log_error(OS_LOG_DEFAULT, "%{public}s", s);
+  } else {
+    asl_log(nullptr, nullptr, ASL_LEVEL_ERR, "%s", s);
+  }
+#endif
+}
+
+// buffer to store crash report application information
+static char crashreporter_info_buff[__sanitizer::kErrorMessageBufferSize] = {};
+static BlockingMutex crashreporter_info_mutex(LINKER_INITIALIZED);
+
+extern "C" {
+// Integrate with crash reporter libraries.
+#if HAVE_CRASHREPORTERCLIENT_H
+CRASH_REPORTER_CLIENT_HIDDEN
+struct crashreporter_annotations_t gCRAnnotations
+    __attribute__((section("__DATA," CRASHREPORTER_ANNOTATIONS_SECTION))) = {
+        CRASHREPORTER_ANNOTATIONS_VERSION,
+        0,
+        0,
+        0,
+        0,
+        0,
+        0,
+#if CRASHREPORTER_ANNOTATIONS_VERSION > 4
+        0,
+#endif
+};
+
+#else
+// fall back to old crashreporter api
+static const char *__crashreporter_info__ __attribute__((__used__)) =
+    &crashreporter_info_buff[0];
+asm(".desc ___crashreporter_info__, 0x10");
+#endif
+
+}  // extern "C"
+
+static void CRAppendCrashLogMessage(const char *msg) {
+  BlockingMutexLock l(&crashreporter_info_mutex);
+  internal_strlcat(crashreporter_info_buff, msg,
+                   sizeof(crashreporter_info_buff));
+#if HAVE_CRASHREPORTERCLIENT_H
+  (void)CRSetCrashLogMessage(crashreporter_info_buff);
  #endif
  }
  
@@ -947,7 +1025,7 @@ void MaybeReexec() {
    if (DyldNeedsEnvVariable() && !lib_is_in_env) {
      // DYLD_INSERT_LIBRARIES is not set or does not contain the runtime
      // library.
-    InternalScopedString program_name(1024);
+    InternalMmapVector<char> program_name(1024);
      uint32_t buf_size = program_name.size();
      _NSGetExecutablePath(program_name.data(), &buf_size);
      char *new_env = const_cast<char*>(info.dli_fname);
@@ -1066,7 +1144,7 @@ char **GetArgv() {
    return *_NSGetArgv();
  }
  
-#if SANITIZER_IOS
+#if SANITIZER_IOS && !SANITIZER_IOSSIM
  // The task_vm_info struct is normally provided by the macOS SDK, but we need
  // fields only available in 10.12+. Declare the struct manually to be able to
  // build against older SDKs.
@@ -1106,26 +1184,35 @@ static uptr GetTaskInfoMaxAddress() {
  
  uptr GetMaxUserVirtualAddress() {
    static uptr max_vm = GetTaskInfoMaxAddress();
-  if (max_vm != 0)
-    return max_vm - 1;
+  if (max_vm != 0) {
+    const uptr ret_value = max_vm - 1;
+    CHECK_LE(ret_value, SANITIZER_MMAP_RANGE_SIZE);
+    return ret_value;
+  }
  
    // xnu cannot provide vm address limit
  # if SANITIZER_WORDSIZE == 32
-  return 0xffe00000 - 1;
+  constexpr uptr fallback_max_vm = 0xffe00000 - 1;
  # else
-  return 0x200000000 - 1;
+  constexpr uptr fallback_max_vm = 0x200000000 - 1;
  # endif
+  static_assert(fallback_max_vm <= SANITIZER_MMAP_RANGE_SIZE,
+                "Max virtual address must be less than mmap range size.");
+  return fallback_max_vm;
  }
  
  #else // !SANITIZER_IOS
  
  uptr GetMaxUserVirtualAddress() {
  # if SANITIZER_WORDSIZE == 64
-  return (1ULL << 47) - 1;  // 0x00007fffffffffffUL;
+  constexpr uptr max_vm = (1ULL << 47) - 1;  // 0x00007fffffffffffUL;
  # else // SANITIZER_WORDSIZE == 32
    static_assert(SANITIZER_WORDSIZE == 32, "Wrong wordsize");
-  return (1ULL << 32) - 1;  // 0xffffffff;
+  constexpr uptr max_vm = (1ULL << 32) - 1;  // 0xffffffff;
  # endif
+  static_assert(max_vm <= SANITIZER_MMAP_RANGE_SIZE,
+                "Max virtual address must be less than mmap range size.");
+  return max_vm;
  }
  #endif
  
@@ -1180,6 +1267,12 @@ uptr MapDynamicShadow(uptr shadow_size_bytes, uptr shadow_scale,
    return shadow_start;
  }
  
+uptr MapDynamicShadowAndAliases(uptr shadow_size, uptr alias_size,
+                                uptr num_aliases, uptr ring_buffer_size) {
+  CHECK(false && "HWASan aliasing is unimplemented on Mac");
+  return 0;
+}
+
  uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
                                uptr *largest_gap_found,
                                uptr *max_occupied_addr) {
diff --git a/libsanitizer/sanitizer_common/sanitizer_mac.h b/libsanitizer/sanitizer_common/sanitizer_mac.h
index a2c42b3bf4f..0b6af5a3c0e 100644
--- a/libsanitizer/sanitizer_common/sanitizer_mac.h
+++ b/libsanitizer/sanitizer_common/sanitizer_mac.h
@@ -14,26 +14,6 @@
  
  #include "sanitizer_common.h"
  #include "sanitizer_platform.h"
-
-/* TARGET_OS_OSX is not present in SDKs before Darwin16 (macOS 10.12) use
-   TARGET_OS_MAC (we have no support for iOS in any form for these versions,
-   so there's no ambiguity).  */
-#if !defined(TARGET_OS_OSX) && TARGET_OS_MAC
-# define TARGET_OS_OSX 1
-#endif
-
-/* Other TARGET_OS_xxx are not present on earlier versions, define them to
-   0 (we have no support for them; they are not valid targets anyway).  */
-#ifndef TARGET_OS_IOS
-#define TARGET_OS_IOS 0
-#endif
-#ifndef TARGET_OS_TV
-#define TARGET_OS_TV 0
-#endif
-#ifndef TARGET_OS_WATCH
-#define TARGET_OS_WATCH 0
-#endif
-
  #if SANITIZER_MAC
  #include "sanitizer_posix.h"
  
@@ -84,22 +64,5 @@ void RestrictMemoryToMaxAddress(uptr max_address);
  
  }  // namespace __sanitizer
  
-extern "C" {
-static char __crashreporter_info_buff__[__sanitizer::kErrorMessageBufferSize] =
-  {};
-static const char *__crashreporter_info__ __attribute__((__used__)) =
-  &__crashreporter_info_buff__[0];
-asm(".desc ___crashreporter_info__, 0x10");
-} // extern "C"
-
-namespace __sanitizer {
-static BlockingMutex crashreporter_info_mutex(LINKER_INITIALIZED);
-
-inline void CRAppendCrashLogMessage(const char *msg) {
-  BlockingMutexLock l(&crashreporter_info_mutex);
-  internal_strlcat(__crashreporter_info_buff__, msg,
-                   sizeof(__crashreporter_info_buff__)); }
-}  // namespace __sanitizer
-
  #endif  // SANITIZER_MAC
  #endif  // SANITIZER_MAC_H
diff --git a/libsanitizer/sanitizer_common/sanitizer_malloc_mac.inc b/libsanitizer/sanitizer_common/sanitizer_malloc_mac.inc
index 647bcdfe105..e3b664f68b6 100644
--- a/libsanitizer/sanitizer_common/sanitizer_malloc_mac.inc
+++ b/libsanitizer/sanitizer_common/sanitizer_malloc_mac.inc
@@ -120,11 +120,7 @@ INTERCEPTOR(int, malloc_make_nonpurgeable, void *ptr) {
  
  INTERCEPTOR(void, malloc_set_zone_name, malloc_zone_t *zone, const char *name) {
    COMMON_MALLOC_ENTER();
-  // Allocate |sizeof(COMMON_MALLOC_ZONE_NAME "-") + internal_strlen(name)|
-  // bytes.
-  size_t buflen =
-      sizeof(COMMON_MALLOC_ZONE_NAME "-") + (name ? internal_strlen(name) : 0);
-  InternalScopedString new_name(buflen);
+  InternalScopedString new_name;
    if (name && zone->introspect == sanitizer_zone.introspect) {
      new_name.append(COMMON_MALLOC_ZONE_NAME "-%s", name);
      name = new_name.data();
diff --git a/libsanitizer/sanitizer_common/sanitizer_netbsd.cpp b/libsanitizer/sanitizer_common/sanitizer_netbsd.cpp
index 98ac7365da0..ac20f915fef 100644
--- a/libsanitizer/sanitizer_common/sanitizer_netbsd.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_netbsd.cpp
@@ -105,6 +105,12 @@ uptr internal_munmap(void *addr, uptr length) {
    return _REAL(munmap, addr, length);
  }
  
+uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags,
+                     void *new_address) {
+  CHECK(false && "internal_mremap is unimplemented on NetBSD");
+  return 0;
+}
+
  int internal_mprotect(void *addr, uptr length, int prot) {
    DEFINE__REAL(int, mprotect, void *a, uptr b, int c);
    return _REAL(mprotect, addr, length, prot);
diff --git a/libsanitizer/sanitizer_common/sanitizer_platform.h b/libsanitizer/sanitizer_common/sanitizer_platform.h
index b2372a025c0..2f6458431c8 100644
--- a/libsanitizer/sanitizer_common/sanitizer_platform.h
+++ b/libsanitizer/sanitizer_common/sanitizer_platform.h
@@ -19,12 +19,25 @@
  # error "This operating system is not supported"
  #endif
  
+// Get __GLIBC__ on a glibc platform. Exclude Android: features.h includes C
+// function declarations into a .S file which doesn't compile.
+// https://crbug.com/1162741
+#if __has_include(<features.h>) && !defined(__ANDROID__)
+#include <features.h>
+#endif
+
  #if defined(__linux__)
  # define SANITIZER_LINUX   1
  #else
  # define SANITIZER_LINUX   0
  #endif
  
+#if defined(__GLIBC__)
+# define SANITIZER_GLIBC   1
+#else
+# define SANITIZER_GLIBC   0
+#endif
+
  #if defined(__FreeBSD__)
  # define SANITIZER_FREEBSD 1
  #else
@@ -46,6 +59,11 @@
  #if defined(__APPLE__)
  # define SANITIZER_MAC     1
  # include <TargetConditionals.h>
+# if TARGET_OS_OSX
+#  define SANITIZER_OSX    1
+# else
+#  define SANITIZER_OSX    0
+# endif
  # if TARGET_OS_IPHONE
  #  define SANITIZER_IOS    1
  # else
@@ -60,6 +78,7 @@
  # define SANITIZER_MAC     0
  # define SANITIZER_IOS     0
  # define SANITIZER_IOSSIM  0
+# define SANITIZER_OSX     0
  #endif
  
  #if defined(__APPLE__) && TARGET_OS_IPHONE && TARGET_OS_WATCH
@@ -247,8 +266,12 @@
  #define SANITIZER_MMAP_RANGE_SIZE FIRST_32_SECOND_64(1ULL << 32, 1ULL << 38)
  #elif defined(__aarch64__)
  # if SANITIZER_MAC
-// Darwin iOS/ARM64 has a 36-bit VMA, 64GiB VM
-#  define SANITIZER_MMAP_RANGE_SIZE FIRST_32_SECOND_64(1ULL << 32, 1ULL << 36)
+#  if SANITIZER_OSX || SANITIZER_IOSSIM
+#   define SANITIZER_MMAP_RANGE_SIZE FIRST_32_SECOND_64(1ULL << 32, 1ULL << 47)
+#  else
+    // Darwin iOS/ARM64 has a 36-bit VMA, 64GiB VM
+#   define SANITIZER_MMAP_RANGE_SIZE FIRST_32_SECOND_64(1ULL << 32, 1ULL << 36)
+#  endif
  # else
  #  define SANITIZER_MMAP_RANGE_SIZE FIRST_32_SECOND_64(1ULL << 32, 1ULL << 48)
  # endif
diff --git a/libsanitizer/sanitizer_common/sanitizer_platform_interceptors.h b/libsanitizer/sanitizer_common/sanitizer_platform_interceptors.h
index 18bab346ce6..731df710df5 100644
--- a/libsanitizer/sanitizer_common/sanitizer_platform_interceptors.h
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_interceptors.h
@@ -46,6 +46,12 @@
  #define SI_LINUX_NOT_ANDROID 0
  #endif
  
+#if SANITIZER_GLIBC
+#define SI_GLIBC 1
+#else
+#define SI_GLIBC 0
+#endif
+
  #if SANITIZER_ANDROID
  #define SI_ANDROID 1
  #else
@@ -159,7 +165,7 @@
    SANITIZER_INTERCEPT_MEMCMP &&  \
        ((SI_POSIX && _GNU_SOURCE) || SI_NETBSD || SI_FREEBSD)
  #define SANITIZER_INTERCEPT_STRNDUP SI_POSIX
-#define SANITIZER_INTERCEPT___STRNDUP SI_LINUX_NOT_FREEBSD
+#define SANITIZER_INTERCEPT___STRNDUP SI_GLIBC
  #if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \
      __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 1070
  #define SI_MAC_DEPLOYMENT_BELOW_10_7 1
@@ -183,8 +189,8 @@
  #define SANITIZER_INTERCEPT_FPUTS SI_POSIX
  #define SANITIZER_INTERCEPT_PUTS SI_POSIX
  
-#define SANITIZER_INTERCEPT_PREAD64 SI_LINUX_NOT_ANDROID || SI_SOLARIS32
-#define SANITIZER_INTERCEPT_PWRITE64 SI_LINUX_NOT_ANDROID || SI_SOLARIS32
+#define SANITIZER_INTERCEPT_PREAD64 (SI_GLIBC || SI_SOLARIS32)
+#define SANITIZER_INTERCEPT_PWRITE64 (SI_GLIBC || SI_SOLARIS32)
  
  #define SANITIZER_INTERCEPT_READV SI_POSIX
  #define SANITIZER_INTERCEPT_WRITEV SI_POSIX
@@ -192,8 +198,8 @@
  #define SANITIZER_INTERCEPT_PREADV \
    (SI_FREEBSD || SI_NETBSD || SI_LINUX_NOT_ANDROID)
  #define SANITIZER_INTERCEPT_PWRITEV SI_LINUX_NOT_ANDROID
-#define SANITIZER_INTERCEPT_PREADV64 SI_LINUX_NOT_ANDROID
-#define SANITIZER_INTERCEPT_PWRITEV64 SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_PREADV64 SI_GLIBC
+#define SANITIZER_INTERCEPT_PWRITEV64 SI_GLIBC
  
  #define SANITIZER_INTERCEPT_PRCTL SI_LINUX
  
@@ -201,16 +207,16 @@
  #define SANITIZER_INTERCEPT_STRPTIME SI_POSIX
  
  #define SANITIZER_INTERCEPT_SCANF SI_POSIX
-#define SANITIZER_INTERCEPT_ISOC99_SCANF SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_ISOC99_SCANF SI_GLIBC
  
  #ifndef SANITIZER_INTERCEPT_PRINTF
  #define SANITIZER_INTERCEPT_PRINTF SI_POSIX
  #define SANITIZER_INTERCEPT_PRINTF_L (SI_FREEBSD || SI_NETBSD)
-#define SANITIZER_INTERCEPT_ISOC99_PRINTF SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_ISOC99_PRINTF SI_GLIBC
  #endif
  
  #define SANITIZER_INTERCEPT___PRINTF_CHK \
-  (SANITIZER_INTERCEPT_PRINTF && SI_LINUX_NOT_ANDROID)
+  (SANITIZER_INTERCEPT_PRINTF && SI_GLIBC)
  
  #define SANITIZER_INTERCEPT_FREXP SI_NOT_FUCHSIA
  #define SANITIZER_INTERCEPT_FREXPF_FREXPL SI_POSIX
@@ -220,13 +226,11 @@
    (SI_FREEBSD || SI_NETBSD || SI_MAC || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_GETPWENT \
    (SI_FREEBSD || SI_NETBSD || SI_MAC || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
-#define SANITIZER_INTERCEPT_FGETGRENT_R \
-  (SI_FREEBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
+#define SANITIZER_INTERCEPT_FGETGRENT_R (SI_GLIBC || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_FGETPWENT SI_LINUX_NOT_ANDROID || SI_SOLARIS
  #define SANITIZER_INTERCEPT_GETPWENT_R \
-  (SI_FREEBSD || SI_NETBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
-#define SANITIZER_INTERCEPT_FGETPWENT_R \
-  (SI_FREEBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
+  (SI_FREEBSD || SI_NETBSD || SI_GLIBC || SI_SOLARIS)
+#define SANITIZER_INTERCEPT_FGETPWENT_R (SI_FREEBSD || SI_GLIBC || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_SETPWENT \
    (SI_MAC || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_CLOCK_GETTIME \
@@ -234,8 +238,8 @@
  #define SANITIZER_INTERCEPT_CLOCK_GETCPUCLOCKID SI_LINUX
  #define SANITIZER_INTERCEPT_GETITIMER SI_POSIX
  #define SANITIZER_INTERCEPT_TIME SI_POSIX
-#define SANITIZER_INTERCEPT_GLOB SI_LINUX_NOT_ANDROID || SI_SOLARIS
-#define SANITIZER_INTERCEPT_GLOB64 SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_GLOB (SI_GLIBC || SI_SOLARIS)
+#define SANITIZER_INTERCEPT_GLOB64 SI_GLIBC
  #define SANITIZER_INTERCEPT_WAIT SI_POSIX
  #define SANITIZER_INTERCEPT_INET SI_POSIX
  #define SANITIZER_INTERCEPT_PTHREAD_GETSCHEDPARAM SI_POSIX
@@ -250,8 +254,7 @@
    (SI_FREEBSD || SI_LINUX_NOT_ANDROID)
  #define SANITIZER_INTERCEPT_GETHOSTBYADDR_R \
    (SI_FREEBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
-#define SANITIZER_INTERCEPT_GETHOSTENT_R \
-  (SI_FREEBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
+#define SANITIZER_INTERCEPT_GETHOSTENT_R (SI_FREEBSD || SI_GLIBC || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_GETSOCKOPT SI_POSIX
  #define SANITIZER_INTERCEPT_ACCEPT SI_POSIX
  #define SANITIZER_INTERCEPT_ACCEPT4 (SI_LINUX_NOT_ANDROID || SI_NETBSD)
@@ -296,8 +299,7 @@
    (SI_FREEBSD || SI_NETBSD || SI_MAC || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_TCGETATTR SI_LINUX_NOT_ANDROID || SI_SOLARIS
  #define SANITIZER_INTERCEPT_REALPATH SI_POSIX
-#define SANITIZER_INTERCEPT_CANONICALIZE_FILE_NAME \
-  (SI_LINUX_NOT_ANDROID || SI_SOLARIS)
+#define SANITIZER_INTERCEPT_CANONICALIZE_FILE_NAME (SI_GLIBC || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_CONFSTR \
    (SI_FREEBSD || SI_NETBSD || SI_MAC || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_SCHED_GETAFFINITY SI_LINUX_NOT_ANDROID
@@ -324,7 +326,7 @@
  #define SANITIZER_INTERCEPT_SIGPROCMASK SI_POSIX
  #define SANITIZER_INTERCEPT_PTHREAD_SIGMASK SI_POSIX
  #define SANITIZER_INTERCEPT_BACKTRACE \
-  (SI_FREEBSD || SI_NETBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
+  (SI_FREEBSD || SI_NETBSD || SI_GLIBC || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_GETMNTENT SI_LINUX
  #define SANITIZER_INTERCEPT_GETMNTENT_R SI_LINUX_NOT_ANDROID
  #define SANITIZER_INTERCEPT_STATFS \
@@ -342,11 +344,11 @@
  #define SANITIZER_INTERCEPT_SHMCTL                                       \
    (((SI_FREEBSD || SI_LINUX_NOT_ANDROID) && SANITIZER_WORDSIZE == 64) || \
     SI_NETBSD || SI_SOLARIS)  // NOLINT
-#define SANITIZER_INTERCEPT_RANDOM_R SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_RANDOM_R SI_GLIBC
  #define SANITIZER_INTERCEPT_PTHREAD_ATTR_GET SI_POSIX
  #define SANITIZER_INTERCEPT_PTHREAD_ATTR_GETINHERITSCHED \
    (SI_FREEBSD || SI_NETBSD || SI_MAC || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
-#define SANITIZER_INTERCEPT_PTHREAD_ATTR_GETAFFINITY_NP SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_PTHREAD_ATTR_GETAFFINITY_NP SI_GLIBC
  #define SANITIZER_INTERCEPT_PTHREAD_ATTR_GET_SCHED SI_POSIX
  #define SANITIZER_INTERCEPT_PTHREAD_MUTEXATTR_GETPSHARED \
    (SI_POSIX && !SI_NETBSD)
@@ -360,7 +362,7 @@
  #define SANITIZER_INTERCEPT_PTHREAD_MUTEXATTR_GETROBUST_NP SI_LINUX_NOT_ANDROID
  #define SANITIZER_INTERCEPT_PTHREAD_RWLOCKATTR_GETPSHARED \
    (SI_POSIX && !SI_NETBSD)
-#define SANITIZER_INTERCEPT_PTHREAD_RWLOCKATTR_GETKIND_NP SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_PTHREAD_RWLOCKATTR_GETKIND_NP SI_GLIBC
  #define SANITIZER_INTERCEPT_PTHREAD_CONDATTR_GETPSHARED (SI_POSIX && !SI_NETBSD)
  #define SANITIZER_INTERCEPT_PTHREAD_CONDATTR_GETCLOCK \
    (SI_LINUX_NOT_ANDROID || SI_SOLARIS)
@@ -368,7 +370,7 @@
    (SI_LINUX_NOT_ANDROID && !SI_NETBSD)
  #define SANITIZER_INTERCEPT_THR_EXIT SI_FREEBSD
  #define SANITIZER_INTERCEPT_TMPNAM SI_POSIX
-#define SANITIZER_INTERCEPT_TMPNAM_R SI_LINUX_NOT_ANDROID || SI_SOLARIS
+#define SANITIZER_INTERCEPT_TMPNAM_R (SI_GLIBC || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_PTSNAME SI_LINUX
  #define SANITIZER_INTERCEPT_PTSNAME_R SI_LINUX
  #define SANITIZER_INTERCEPT_TTYNAME SI_POSIX
@@ -381,7 +383,7 @@
  #define SANITIZER_INTERCEPT_LGAMMAL (SI_POSIX && !SI_NETBSD)
  #define SANITIZER_INTERCEPT_LGAMMA_R (SI_FREEBSD || SI_LINUX || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_LGAMMAL_R SI_LINUX_NOT_ANDROID || SI_SOLARIS
-#define SANITIZER_INTERCEPT_DRAND48_R SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_DRAND48_R SI_GLIBC
  #define SANITIZER_INTERCEPT_RAND_R \
    (SI_FREEBSD || SI_NETBSD || SI_MAC || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_ICONV \
@@ -396,12 +398,12 @@
    (SI_LINUX || SI_FREEBSD || SI_NETBSD || SI_MAC || SI_SOLARIS)
  
  #define SANITIZER_INTERCEPT_PTHREAD_MUTEX SI_POSIX
-#define SANITIZER_INTERCEPT___PTHREAD_MUTEX SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT___PTHREAD_MUTEX SI_GLIBC
  #define SANITIZER_INTERCEPT___LIBC_MUTEX SI_NETBSD
  #define SANITIZER_INTERCEPT_PTHREAD_SETNAME_NP \
-  (SI_FREEBSD || SI_NETBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
+  (SI_FREEBSD || SI_NETBSD || SI_GLIBC || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_PTHREAD_GETNAME_NP \
-  (SI_FREEBSD || SI_NETBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
+  (SI_FREEBSD || SI_NETBSD || SI_GLIBC || SI_SOLARIS)
  
  #define SANITIZER_INTERCEPT_TLS_GET_ADDR \
    (SI_FREEBSD || SI_NETBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
@@ -419,19 +421,19 @@
  #else
  #define SANITIZER_INTERCEPT_AEABI_MEM 0
  #endif
-#define SANITIZER_INTERCEPT___BZERO SI_MAC || SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT___BZERO SI_MAC || SI_GLIBC
  #define SANITIZER_INTERCEPT_BZERO SI_LINUX_NOT_ANDROID
  #define SANITIZER_INTERCEPT_FTIME (!SI_FREEBSD && !SI_NETBSD && SI_POSIX)
-#define SANITIZER_INTERCEPT_XDR SI_LINUX_NOT_ANDROID || SI_SOLARIS
-#define SANITIZER_INTERCEPT_XDRREC SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_XDR (SI_GLIBC || SI_SOLARIS)
+#define SANITIZER_INTERCEPT_XDRREC SI_GLIBC
  #define SANITIZER_INTERCEPT_TSEARCH \
    (SI_LINUX_NOT_ANDROID || SI_MAC || SI_NETBSD || SI_SOLARIS)
-#define SANITIZER_INTERCEPT_LIBIO_INTERNALS SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_LIBIO_INTERNALS SI_GLIBC
  #define SANITIZER_INTERCEPT_FOPEN SI_POSIX
-#define SANITIZER_INTERCEPT_FOPEN64 SI_LINUX_NOT_ANDROID || SI_SOLARIS32
+#define SANITIZER_INTERCEPT_FOPEN64 (SI_GLIBC || SI_SOLARIS32)
  #define SANITIZER_INTERCEPT_OPEN_MEMSTREAM \
    (SI_LINUX_NOT_ANDROID || SI_NETBSD || SI_SOLARIS)
-#define SANITIZER_INTERCEPT_OBSTACK SI_LINUX_NOT_ANDROID
+#define SANITIZER_INTERCEPT_OBSTACK SI_GLIBC
  #define SANITIZER_INTERCEPT_FFLUSH SI_POSIX
  #define SANITIZER_INTERCEPT_FCLOSE SI_POSIX
  
@@ -456,7 +458,7 @@
  #define SANITIZER_INTERCEPT_CTERMID_R (SI_MAC || SI_FREEBSD || SI_SOLARIS)
  
  #define SANITIZER_INTERCEPTOR_HOOKS \
-  (SI_LINUX || SI_MAC || SI_WINDOWS || SI_NETBSD)
+  (SI_LINUX || SI_MAC || SI_WINDOWS || SI_FREEBSD || SI_NETBSD || SI_SOLARIS)
  #define SANITIZER_INTERCEPT_RECV_RECVFROM SI_POSIX
  #define SANITIZER_INTERCEPT_SEND_SENDTO SI_POSIX
  #define SANITIZER_INTERCEPT_EVENTFD_READ_WRITE SI_LINUX
@@ -479,20 +481,12 @@
  
  #define SANITIZER_INTERCEPT_MMAP SI_POSIX
  #define SANITIZER_INTERCEPT_MMAP64 SI_LINUX_NOT_ANDROID
-#define SANITIZER_INTERCEPT_MALLOPT_AND_MALLINFO                             \
-  (!SI_FREEBSD && !SI_MAC && !SI_NETBSD && SI_NOT_FUCHSIA && SI_NOT_RTEMS && \
-   !SI_SOLARIS)  // NOLINT
+#define SANITIZER_INTERCEPT_MALLOPT_AND_MALLINFO (SI_GLIBC || SI_ANDROID)
  #define SANITIZER_INTERCEPT_MEMALIGN \
    (!SI_FREEBSD && !SI_MAC && !SI_NETBSD && SI_NOT_RTEMS)
-#define SANITIZER_INTERCEPT___LIBC_MEMALIGN                               \
-  (!SI_FREEBSD && !SI_MAC && !SI_NETBSD && !SI_OPENBSD && SI_NOT_RTEMS && \
-   !SI_ANDROID)  // NOLINT
-#define SANITIZER_INTERCEPT_PVALLOC                                          \
-  (!SI_FREEBSD && !SI_MAC && !SI_NETBSD && SI_NOT_FUCHSIA && SI_NOT_RTEMS && \
-   !SI_SOLARIS)  // NOLINT
-#define SANITIZER_INTERCEPT_CFREE                                            \
-  (!SI_FREEBSD && !SI_MAC && !SI_NETBSD && SI_NOT_FUCHSIA && SI_NOT_RTEMS && \
-   !SI_SOLARIS && !SANITIZER_ANDROID)  // NOLINT
+#define SANITIZER_INTERCEPT___LIBC_MEMALIGN SI_GLIBC
+#define SANITIZER_INTERCEPT_PVALLOC (SI_GLIBC || SI_ANDROID)
+#define SANITIZER_INTERCEPT_CFREE (SI_GLIBC && !SANITIZER_RISCV64)
  #define SANITIZER_INTERCEPT_REALLOCARRAY SI_POSIX
  #define SANITIZER_INTERCEPT_ALIGNED_ALLOC (!SI_MAC && SI_NOT_RTEMS)
  #define SANITIZER_INTERCEPT_MALLOC_USABLE_SIZE (!SI_MAC && !SI_NETBSD)
@@ -532,7 +526,7 @@
  #define SANITIZER_INTERCEPT_STRMODE (SI_NETBSD || SI_FREEBSD)
  #define SANITIZER_INTERCEPT_TTYENT SI_NETBSD
  #define SANITIZER_INTERCEPT_PROTOENT (SI_NETBSD || SI_LINUX)
-#define SANITIZER_INTERCEPT_PROTOENT_R (SI_LINUX_NOT_ANDROID)
+#define SANITIZER_INTERCEPT_PROTOENT_R SI_GLIBC
  #define SANITIZER_INTERCEPT_NETENT SI_NETBSD
  #define SANITIZER_INTERCEPT_SETVBUF \
    (SI_NETBSD || SI_FREEBSD || SI_LINUX || SI_MAC)
@@ -583,7 +577,7 @@
  #define SANITIZER_INTERCEPT_GETENTROPY SI_FREEBSD
  #define SANITIZER_INTERCEPT_QSORT \
    (SI_POSIX && !SI_IOSSIM && !SI_WATCHOS && !SI_TVOS && !SI_ANDROID)
-#define SANITIZER_INTERCEPT_QSORT_R (SI_LINUX && !SI_ANDROID)
+#define SANITIZER_INTERCEPT_QSORT_R SI_GLIBC
  // sigaltstack on i386 macOS cannot be intercepted due to setjmp()
  // calling it and assuming that it does not clobber registers.
  #define SANITIZER_INTERCEPT_SIGALTSTACK \
@@ -591,4 +585,25 @@
  #define SANITIZER_INTERCEPT_UNAME (SI_POSIX && !SI_FREEBSD)
  #define SANITIZER_INTERCEPT___XUNAME SI_FREEBSD
  
+// This macro gives a way for downstream users to override the above
+// interceptor macros irrespective of the platform they are on. They have
+// to do two things:
+// 1. Build compiler-rt with -DSANITIZER_OVERRIDE_INTERCEPTORS.
+// 2. Provide a header file named sanitizer_intercept_overriders.h in the
+//    include path for their compiler-rt build.
+// An example of an overrider for strlen interceptor that one can list in
+// sanitizer_intercept_overriders.h is as follows:
+//
+// #ifdef SANITIZER_INTERCEPT_STRLEN
+// #undef SANITIZER_INTERCEPT_STRLEN
+// #define SANITIZER_INTERCEPT_STRLEN <value of choice>
+// #endif
+//
+// This "feature" is useful for downstream users who do not want some of
+// their libc funtions to be intercepted. They can selectively disable
+// interception of those functions.
+#ifdef SANITIZER_OVERRIDE_INTERCEPTORS
+#include <sanitizer_intercept_overriders.h>
+#endif
+
  #endif  // #ifndef SANITIZER_PLATFORM_INTERCEPTORS_H
diff --git a/libsanitizer/sanitizer_common/sanitizer_platform_limits_freebsd.cpp b/libsanitizer/sanitizer_common/sanitizer_platform_limits_freebsd.cpp
index b1c15be58de..b5a45ae72cd 100644
--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_freebsd.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_freebsd.cpp
@@ -35,7 +35,10 @@
  #include <sys/stat.h>
  #include <sys/statvfs.h>
  #include <sys/time.h>
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-W#warnings"
  #include <sys/timeb.h>
+#pragma clang diagnostic pop
  #include <sys/times.h>
  #include <sys/timespec.h>
  #include <sys/types.h>
diff --git a/libsanitizer/sanitizer_common/sanitizer_platform_limits_linux.cpp b/libsanitizer/sanitizer_common/sanitizer_platform_limits_linux.cpp
index f22f5039128..c51327e1269 100644
--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_linux.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_linux.cpp
@@ -26,12 +26,9 @@
  
  // With old kernels (and even new kernels on powerpc) asm/stat.h uses types that
  // are not defined anywhere in userspace headers. Fake them. This seems to work
-// fine with newer headers, too.  Beware that with <sys/stat.h>, struct stat
-// takes the form of struct stat64 on 32-bit platforms if _FILE_OFFSET_BITS=64.
-// Also, for some platforms (e.g. mips) there are additional members in the
-// <sys/stat.h> struct stat:s.
+// fine with newer headers, too.
  #include <linux/posix_types.h>
-#if defined(__x86_64__)
+#if defined(__x86_64__) ||  defined(__mips__)
  #include <sys/stat.h>
  #else
  #define ino_t __kernel_ino_t
diff --git a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cpp b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cpp
index 1427cec48c4..35a690cba5c 100644
--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cpp
@@ -11,18 +11,19 @@
  // Sizes and layouts of platform-specific POSIX data structures.
  //===----------------------------------------------------------------------===//
  
-#include "sanitizer_platform.h"
-
-#if SANITIZER_LINUX || SANITIZER_MAC
+#if defined(__linux__) || defined(__APPLE__)
  // Tests in this file assume that off_t-dependent data structures match the
  // libc ABI. For example, struct dirent here is what readdir() function (as
  // exported from libc) returns, and not the user-facing "dirent", which
  // depends on _FILE_OFFSET_BITS setting.
  // To get this "true" dirent definition, we undefine _FILE_OFFSET_BITS below.
-#ifdef _FILE_OFFSET_BITS
  #undef _FILE_OFFSET_BITS
  #endif
  
+// Must go after undef _FILE_OFFSET_BITS.
+#include "sanitizer_platform.h"
+
+#if SANITIZER_LINUX || SANITIZER_MAC
  // Must go after undef _FILE_OFFSET_BITS.
  #include "sanitizer_glibc_version.h"
  
@@ -37,6 +38,7 @@
  #include <pwd.h>
  #include <signal.h>
  #include <stddef.h>
+#include <stdio.h>
  #include <sys/mman.h>
  #include <sys/resource.h>
  #include <sys/socket.h>
@@ -58,7 +60,6 @@
  #endif
  
  #if !SANITIZER_ANDROID
-#include <fstab.h>
  #include <sys/mount.h>
  #include <sys/timeb.h>
  #include <utmpx.h>
@@ -110,20 +111,31 @@ typedef struct user_fpregs elf_fpregset_t;
  #include <wordexp.h>
  #endif
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
-#include <glob.h>
-#include <obstack.h>
-#include <mqueue.h>
+#if SANITIZER_LINUX
+#if SANITIZER_GLIBC
+#include <fstab.h>
  #include <net/if_ppp.h>
  #include <netax25/ax25.h>
  #include <netipx/ipx.h>
  #include <netrom/netrom.h>
+#include <obstack.h>
  #if HAVE_RPC_XDR_H
  # include <rpc/xdr.h>
  #endif
  #include <scsi/scsi.h>
-#include <sys/mtio.h>
+#else
+#include <linux/if_ppp.h>
+#include <linux/kd.h>
+#include <linux/ppp_defs.h>
+#endif  // SANITIZER_GLIBC
+
+#if SANITIZER_ANDROID
+#include <linux/mtio.h>
+#else
+#include <glob.h>
+#include <mqueue.h>
  #include <sys/kd.h>
+#include <sys/mtio.h>
  #include <sys/shm.h>
  #include <sys/statvfs.h>
  #include <sys/timex.h>
@@ -142,20 +154,14 @@ typedef struct user_fpregs elf_fpregset_t;
  #include <sys/msg.h>
  #include <sys/ipc.h>
  #include <crypt.h>
-#endif // SANITIZER_LINUX && !SANITIZER_ANDROID
+#endif  // SANITIZER_ANDROID
  
-#if SANITIZER_ANDROID
-#include <linux/kd.h>
-#include <linux/mtio.h>
-#include <linux/ppp_defs.h>
-#include <linux/if_ppp.h>
-#endif
-
-#if SANITIZER_LINUX
  #include <link.h>
  #include <sys/vfs.h>
  #include <sys/epoll.h>
  #include <linux/capability.h>
+#else
+#include <fstab.h>
  #endif // SANITIZER_LINUX
  
  #if SANITIZER_MAC
@@ -202,8 +208,11 @@ namespace __sanitizer {
    unsigned struct_statfs64_sz = sizeof(struct statfs64);
  #endif // (SANITIZER_MAC && !TARGET_CPU_ARM64) && !SANITIZER_IOS
  
-#if !SANITIZER_ANDROID
+#if SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_MAC
    unsigned struct_fstab_sz = sizeof(struct fstab);
+#endif  // SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD ||
+        // SANITIZER_MAC
+#if !SANITIZER_ANDROID
    unsigned struct_statfs_sz = sizeof(struct statfs);
    unsigned struct_sockaddr_sz = sizeof(struct sockaddr);
    unsigned ucontext_t_sz = sizeof(ucontext_t);
@@ -299,7 +308,7 @@ unsigned struct_ElfW_Phdr_sz = sizeof(ElfW(Phdr));
  unsigned struct_ElfW_Phdr_sz = sizeof(Elf_Phdr);
  #endif
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
+#if SANITIZER_GLIBC
    int glob_nomatch = GLOB_NOMATCH;
    int glob_altdirfunc = GLOB_ALTDIRFUNC;
  #endif
@@ -422,7 +431,9 @@ unsigned struct_ElfW_Phdr_sz = sizeof(Elf_Phdr);
    unsigned struct_input_id_sz = sizeof(struct input_id);
    unsigned struct_mtpos_sz = sizeof(struct mtpos);
    unsigned struct_rtentry_sz = sizeof(struct rtentry);
+#if SANITIZER_GLIBC || SANITIZER_ANDROID
    unsigned struct_termio_sz = sizeof(struct termio);
+#endif
    unsigned struct_vt_consize_sz = sizeof(struct vt_consize);
    unsigned struct_vt_sizes_sz = sizeof(struct vt_sizes);
    unsigned struct_vt_stat_sz = sizeof(struct vt_stat);
@@ -447,7 +458,7 @@ unsigned struct_ElfW_Phdr_sz = sizeof(Elf_Phdr);
    unsigned struct_vt_mode_sz = sizeof(struct vt_mode);
  #endif // SANITIZER_LINUX
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
+#if SANITIZER_GLIBC
    unsigned struct_ax25_parms_struct_sz = sizeof(struct ax25_parms_struct);
    unsigned struct_cyclades_monitor_sz = sizeof(struct cyclades_monitor);
  #if EV_VERSION > (0x010000)
@@ -470,12 +481,10 @@ unsigned struct_ElfW_Phdr_sz = sizeof(Elf_Phdr);
    unsigned struct_sockaddr_ax25_sz = sizeof(struct sockaddr_ax25);
    unsigned struct_unimapdesc_sz = sizeof(struct unimapdesc);
    unsigned struct_unimapinit_sz = sizeof(struct unimapinit);
-#endif // SANITIZER_LINUX && !SANITIZER_ANDROID
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
    unsigned struct_audio_buf_info_sz = sizeof(struct audio_buf_info);
    unsigned struct_ppp_stats_sz = sizeof(struct ppp_stats);
-#endif // (SANITIZER_LINUX || SANITIZER_FREEBSD) && !SANITIZER_ANDROID
+#endif  // SANITIZER_GLIBC
  
  #if !SANITIZER_ANDROID && !SANITIZER_MAC
    unsigned struct_sioc_sg_req_sz = sizeof(struct sioc_sg_req);
@@ -881,6 +890,7 @@ unsigned struct_ElfW_Phdr_sz = sizeof(Elf_Phdr);
    unsigned IOCTL_PIO_UNIMAP = PIO_UNIMAP;
    unsigned IOCTL_PIO_UNIMAPCLR = PIO_UNIMAPCLR;
    unsigned IOCTL_PIO_UNISCRNMAP = PIO_UNISCRNMAP;
+#if SANITIZER_GLIBC
    unsigned IOCTL_SCSI_IOCTL_GET_IDLUN = SCSI_IOCTL_GET_IDLUN;
    unsigned IOCTL_SCSI_IOCTL_PROBE_HOST = SCSI_IOCTL_PROBE_HOST;
    unsigned IOCTL_SCSI_IOCTL_TAGGED_DISABLE = SCSI_IOCTL_TAGGED_DISABLE;
@@ -899,6 +909,7 @@ unsigned struct_ElfW_Phdr_sz = sizeof(Elf_Phdr);
    unsigned IOCTL_SIOCNRGETPARMS = SIOCNRGETPARMS;
    unsigned IOCTL_SIOCNRRTCTL = SIOCNRRTCTL;
    unsigned IOCTL_SIOCNRSETPARMS = SIOCNRSETPARMS;
+#endif
    unsigned IOCTL_TIOCGSERIAL = TIOCGSERIAL;
    unsigned IOCTL_TIOCSERGETMULTI = TIOCSERGETMULTI;
    unsigned IOCTL_TIOCSERSETMULTI = TIOCSERSETMULTI;
@@ -969,7 +980,7 @@ CHECK_SIZE_AND_OFFSET(dl_phdr_info, dlpi_phdr);
  CHECK_SIZE_AND_OFFSET(dl_phdr_info, dlpi_phnum);
  #endif // SANITIZER_LINUX || SANITIZER_FREEBSD
  
-#if (SANITIZER_LINUX || SANITIZER_FREEBSD) && !SANITIZER_ANDROID
+#if SANITIZER_GLIBC || SANITIZER_FREEBSD
  CHECK_TYPE_SIZE(glob_t);
  CHECK_SIZE_AND_OFFSET(glob_t, gl_pathc);
  CHECK_SIZE_AND_OFFSET(glob_t, gl_pathv);
@@ -980,7 +991,7 @@ CHECK_SIZE_AND_OFFSET(glob_t, gl_readdir);
  CHECK_SIZE_AND_OFFSET(glob_t, gl_opendir);
  CHECK_SIZE_AND_OFFSET(glob_t, gl_lstat);
  CHECK_SIZE_AND_OFFSET(glob_t, gl_stat);
-#endif
+#endif  // SANITIZER_GLIBC || SANITIZER_FREEBSD
  
  CHECK_TYPE_SIZE(addrinfo);
  CHECK_SIZE_AND_OFFSET(addrinfo, ai_flags);
@@ -1003,17 +1014,27 @@ CHECK_TYPE_SIZE(iovec);
  CHECK_SIZE_AND_OFFSET(iovec, iov_base);
  CHECK_SIZE_AND_OFFSET(iovec, iov_len);
  
+// In POSIX, int msg_iovlen; socklen_t msg_controllen; socklen_t cmsg_len; but
+// many implementations don't conform to the standard. Since we pick the
+// non-conforming glibc definition, exclude the checks for musl (incompatible
+// sizes but compatible offsets).
  CHECK_TYPE_SIZE(msghdr);
  CHECK_SIZE_AND_OFFSET(msghdr, msg_name);
  CHECK_SIZE_AND_OFFSET(msghdr, msg_namelen);
  CHECK_SIZE_AND_OFFSET(msghdr, msg_iov);
+#if SANITIZER_GLIBC || SANITIZER_ANDROID
  CHECK_SIZE_AND_OFFSET(msghdr, msg_iovlen);
+#endif
  CHECK_SIZE_AND_OFFSET(msghdr, msg_control);
+#if SANITIZER_GLIBC || SANITIZER_ANDROID
  CHECK_SIZE_AND_OFFSET(msghdr, msg_controllen);
+#endif
  CHECK_SIZE_AND_OFFSET(msghdr, msg_flags);
  
  CHECK_TYPE_SIZE(cmsghdr);
+#if SANITIZER_GLIBC || SANITIZER_ANDROID
  CHECK_SIZE_AND_OFFSET(cmsghdr, cmsg_len);
+#endif
  CHECK_SIZE_AND_OFFSET(cmsghdr, cmsg_level);
  CHECK_SIZE_AND_OFFSET(cmsghdr, cmsg_type);
  
@@ -1121,7 +1142,7 @@ CHECK_SIZE_AND_OFFSET(mntent, mnt_passno);
  
  CHECK_TYPE_SIZE(ether_addr);
  
-#if (SANITIZER_LINUX || SANITIZER_FREEBSD) && !SANITIZER_ANDROID
+#if SANITIZER_GLIBC || SANITIZER_FREEBSD
  CHECK_TYPE_SIZE(ipc_perm);
  # if SANITIZER_FREEBSD
  CHECK_SIZE_AND_OFFSET(ipc_perm, key);
@@ -1183,7 +1204,7 @@ CHECK_SIZE_AND_OFFSET(ifaddrs, ifa_dstaddr);
  CHECK_SIZE_AND_OFFSET(ifaddrs, ifa_data);
  #endif
  
-#if SANITIZER_LINUX
+#if SANITIZER_GLIBC || SANITIZER_ANDROID
  COMPILER_CHECK(sizeof(__sanitizer_struct_mallinfo) == sizeof(struct mallinfo));
  #endif
  
@@ -1233,7 +1254,7 @@ COMPILER_CHECK(__sanitizer_XDR_DECODE == XDR_DECODE);
  COMPILER_CHECK(__sanitizer_XDR_FREE == XDR_FREE);
  #endif
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
+#if SANITIZER_GLIBC
  COMPILER_CHECK(sizeof(__sanitizer_FILE) <= sizeof(FILE));
  CHECK_SIZE_AND_OFFSET(FILE, _flags);
  CHECK_SIZE_AND_OFFSET(FILE, _IO_read_ptr);
@@ -1250,9 +1271,7 @@ CHECK_SIZE_AND_OFFSET(FILE, _IO_save_end);
  CHECK_SIZE_AND_OFFSET(FILE, _markers);
  CHECK_SIZE_AND_OFFSET(FILE, _chain);
  CHECK_SIZE_AND_OFFSET(FILE, _fileno);
-#endif
  
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
  COMPILER_CHECK(sizeof(__sanitizer__obstack_chunk) <= sizeof(_obstack_chunk));
  CHECK_SIZE_AND_OFFSET(_obstack_chunk, limit);
  CHECK_SIZE_AND_OFFSET(_obstack_chunk, prev);
@@ -1267,7 +1286,7 @@ CHECK_SIZE_AND_OFFSET(cookie_io_functions_t, read);
  CHECK_SIZE_AND_OFFSET(cookie_io_functions_t, write);
  CHECK_SIZE_AND_OFFSET(cookie_io_functions_t, seek);
  CHECK_SIZE_AND_OFFSET(cookie_io_functions_t, close);
-#endif
+#endif  // SANITIZER_GLIBC
  
  #if SANITIZER_LINUX || SANITIZER_FREEBSD
  CHECK_TYPE_SIZE(sem_t);
diff --git a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h
index 0812039b038..836b178c131 100644
--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h
@@ -83,7 +83,7 @@ const unsigned struct_kernel_stat64_sz = 104;
  #elif defined(__mips__)
  const unsigned struct_kernel_stat_sz = SANITIZER_ANDROID
                                             ? FIRST_32_SECOND_64(104, 128)
-                                           : FIRST_32_SECOND_64(144, 216);
+                                           : FIRST_32_SECOND_64(160, 216);
  const unsigned struct_kernel_stat64_sz = 104;
  #elif defined(__s390__) && !defined(__s390x__)
  const unsigned struct_kernel_stat_sz = 64;
@@ -443,6 +443,8 @@ struct __sanitizer_cmsghdr {
    int cmsg_type;
  };
  #else
+// In POSIX, int msg_iovlen; socklen_t msg_controllen; socklen_t cmsg_len; but
+// many implementations don't conform to the standard.
  struct __sanitizer_msghdr {
    void *msg_name;
    unsigned msg_namelen;
diff --git a/libsanitizer/sanitizer_common/sanitizer_posix.cpp b/libsanitizer/sanitizer_common/sanitizer_posix.cpp
index 2e080098283..f8457a6aac4 100644
--- a/libsanitizer/sanitizer_common/sanitizer_posix.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_posix.cpp
@@ -275,8 +275,8 @@ void ReportFile::Write(const char *buffer, uptr length) {
  
  bool GetCodeRangeForFile(const char *module, uptr *start, uptr *end) {
    MemoryMappingLayout proc_maps(/*cache_enabled*/false);
-  InternalScopedString buff(kMaxPathLength);
-  MemoryMappedSegment segment(buff.data(), kMaxPathLength);
+  InternalMmapVector<char> buff(kMaxPathLength);
+  MemoryMappedSegment segment(buff.data(), buff.size());
    while (proc_maps.Next(&segment)) {
      if (segment.IsExecutable() &&
          internal_strcmp(module, segment.filename) == 0) {
diff --git a/libsanitizer/sanitizer_common/sanitizer_posix.h b/libsanitizer/sanitizer_common/sanitizer_posix.h
index e1a2b48e5cd..b65dae64476 100644
--- a/libsanitizer/sanitizer_common/sanitizer_posix.h
+++ b/libsanitizer/sanitizer_common/sanitizer_posix.h
@@ -40,6 +40,10 @@ uptr internal_write(fd_t fd, const void *buf, uptr count);
  uptr internal_mmap(void *addr, uptr length, int prot, int flags,
                     int fd, u64 offset);
  uptr internal_munmap(void *addr, uptr length);
+#if SANITIZER_LINUX
+uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags,
+                     void *new_address);
+#endif
  int internal_mprotect(void *addr, uptr length, int prot);
  int internal_madvise(uptr addr, uptr length, int advice);
  
diff --git a/libsanitizer/sanitizer_common/sanitizer_posix_libcdep.cpp b/libsanitizer/sanitizer_common/sanitizer_posix_libcdep.cpp
index 7ff48c35851..d1d8e509c4d 100644
--- a/libsanitizer/sanitizer_common/sanitizer_posix_libcdep.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_posix_libcdep.cpp
@@ -143,7 +143,7 @@ void Abort() {
    if (GetHandleSignalMode(SIGABRT) != kHandleSignalNo) {
      struct sigaction sigact;
      internal_memset(&sigact, 0, sizeof(sigact));
-    sigact.sa_sigaction = (sa_sigaction_t)SIG_DFL;
+    sigact.sa_handler = SIG_DFL;
      internal_sigaction(SIGABRT, &sigact, nullptr);
    }
  #endif
diff --git a/libsanitizer/sanitizer_common/sanitizer_printf.cpp b/libsanitizer/sanitizer_common/sanitizer_printf.cpp
index a032787114b..5d16dfde678 100644
--- a/libsanitizer/sanitizer_common/sanitizer_printf.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_printf.cpp
@@ -249,26 +249,21 @@ static void NOINLINE SharedPrintfCodeNoBuffer(bool append_pid,
                                                va_list args) {
    va_list args2;
    va_copy(args2, args);
-  const int kLen = 16 * 1024;
-  int needed_length;
+  InternalMmapVector<char> v;
+  int needed_length = 0;
    char *buffer = local_buffer;
    // First try to print a message using a local buffer, and then fall back to
    // mmaped buffer.
-  for (int use_mmap = 0; use_mmap < 2; use_mmap++) {
+  for (int use_mmap = 0;; use_mmap++) {
      if (use_mmap) {
        va_end(args);
        va_copy(args, args2);
-      buffer = (char*)MmapOrDie(kLen, "Report");
-      buffer_size = kLen;
+      v.resize(needed_length + 1);
+      buffer_size = v.capacity();
+      v.resize(buffer_size);
+      buffer = &v[0];
      }
      needed_length = 0;
-    // Check that data fits into the current buffer.
-#   define CHECK_NEEDED_LENGTH \
-      if (needed_length >= buffer_size) { \
-        if (!use_mmap) continue; \
-        RAW_CHECK_MSG(needed_length < kLen, \
-                      "Buffer in Report is too short!\n"); \
-      }
      // Fuchsia's logging infrastructure always keeps track of the logging
      // process, thread, and timestamp, so never prepend such information.
      if (!SANITIZER_FUCHSIA && append_pid) {
@@ -277,18 +272,20 @@ static void NOINLINE SharedPrintfCodeNoBuffer(bool append_pid,
        if (common_flags()->log_exe_name && exe_name) {
          needed_length += internal_snprintf(buffer, buffer_size,
                                             "==%s", exe_name);
-        CHECK_NEEDED_LENGTH
+        if (needed_length >= buffer_size)
+          continue;
        }
        needed_length += internal_snprintf(
            buffer + needed_length, buffer_size - needed_length, "==%d==", pid);
-      CHECK_NEEDED_LENGTH
+      if (needed_length >= buffer_size)
+        continue;
      }
      needed_length += VSNPrintf(buffer + needed_length,
                                 buffer_size - needed_length, format, args);
-    CHECK_NEEDED_LENGTH
+    if (needed_length >= buffer_size)
+      continue;
      // If the message fit into the buffer, print it and exit.
      break;
-#   undef CHECK_NEEDED_LENGTH
    }
    RawWrite(buffer);
  
@@ -297,9 +294,6 @@ static void NOINLINE SharedPrintfCodeNoBuffer(bool append_pid,
    CallPrintfAndReportCallback(buffer);
    LogMessageOnPrintf(buffer);
  
-  // If we had mapped any memory, clean up.
-  if (buffer != local_buffer)
-    UnmapOrDie((void *)buffer, buffer_size);
    va_end(args2);
  }
  
@@ -346,13 +340,24 @@ int internal_snprintf(char *buffer, uptr length, const char *format, ...) {
  
  FORMAT(2, 3)
  void InternalScopedString::append(const char *format, ...) {
-  CHECK_LT(length_, size());
-  va_list args;
-  va_start(args, format);
-  VSNPrintf(data() + length_, size() - length_, format, args);
-  va_end(args);
-  length_ += internal_strlen(data() + length_);
-  CHECK_LT(length_, size());
+  uptr prev_len = length();
+
+  while (true) {
+    buffer_.resize(buffer_.capacity());
+
+    va_list args;
+    va_start(args, format);
+    uptr sz = VSNPrintf(buffer_.data() + prev_len, buffer_.size() - prev_len,
+                        format, args);
+    va_end(args);
+    if (sz < buffer_.size() - prev_len) {
+      buffer_.resize(prev_len + sz + 1);
+      break;
+    }
+
+    buffer_.reserve(buffer_.capacity() * 2);
+  }
+  CHECK_EQ(buffer_[length()], '\0');
  }
  
  } // namespace __sanitizer
diff --git a/libsanitizer/sanitizer_common/sanitizer_procmaps_common.cpp b/libsanitizer/sanitizer_common/sanitizer_procmaps_common.cpp
index f2cfcffaf47..1b7dd46d8de 100644
--- a/libsanitizer/sanitizer_common/sanitizer_procmaps_common.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_procmaps_common.cpp
@@ -120,7 +120,7 @@ void MemoryMappingLayout::LoadFromCache() {
  void MemoryMappingLayout::DumpListOfModules(
      InternalMmapVectorNoCtor<LoadedModule> *modules) {
    Reset();
-  InternalScopedString module_name(kMaxPathLength);
+  InternalMmapVector<char> module_name(kMaxPathLength);
    MemoryMappedSegment segment(module_name.data(), module_name.size());
    for (uptr i = 0; Next(&segment); i++) {
      const char *cur_name = segment.filename;
diff --git a/libsanitizer/sanitizer_common/sanitizer_procmaps_mac.cpp b/libsanitizer/sanitizer_common/sanitizer_procmaps_mac.cpp
index d02afcfe87a..1f53e3e46d8 100644
--- a/libsanitizer/sanitizer_common/sanitizer_procmaps_mac.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_procmaps_mac.cpp
@@ -354,8 +354,8 @@ bool MemoryMappingLayout::Next(MemoryMappedSegment *segment) {
  void MemoryMappingLayout::DumpListOfModules(
      InternalMmapVectorNoCtor<LoadedModule> *modules) {
    Reset();
-  InternalScopedString module_name(kMaxPathLength);
-  MemoryMappedSegment segment(module_name.data(), kMaxPathLength);
+  InternalMmapVector<char> module_name(kMaxPathLength);
+  MemoryMappedSegment segment(module_name.data(), module_name.size());
    MemoryMappedSegmentData data;
    segment.data_ = &data;
    while (Next(&segment)) {
diff --git a/libsanitizer/sanitizer_common/sanitizer_procmaps_solaris.cpp b/libsanitizer/sanitizer_common/sanitizer_procmaps_solaris.cpp
index 4063ec8deaa..bf813f235bb 100644
--- a/libsanitizer/sanitizer_common/sanitizer_procmaps_solaris.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_procmaps_solaris.cpp
@@ -9,13 +9,13 @@
  // Information about the process mappings (Solaris-specific parts).
  //===----------------------------------------------------------------------===//
  
+// Before Solaris 11.4, <procfs.h> doesn't work in a largefile environment.
+#undef _FILE_OFFSET_BITS
  #include "sanitizer_platform.h"
  #if SANITIZER_SOLARIS
  #include "sanitizer_common.h"
  #include "sanitizer_procmaps.h"
  
-// Before Solaris 11.4, <procfs.h> doesn't work in a largefile environment.
-#undef _FILE_OFFSET_BITS
  #include <procfs.h>
  #include <limits.h>
  
diff --git a/libsanitizer/sanitizer_common/sanitizer_ptrauth.h b/libsanitizer/sanitizer_common/sanitizer_ptrauth.h
index a288068bf94..52003546948 100644
--- a/libsanitizer/sanitizer_common/sanitizer_ptrauth.h
+++ b/libsanitizer/sanitizer_common/sanitizer_ptrauth.h
@@ -11,6 +11,24 @@
  
  #if __has_feature(ptrauth_calls)
  #include <ptrauth.h>
+#elif defined(__ARM_FEATURE_PAC_DEFAULT) && !defined(__APPLE__)
+inline unsigned long ptrauth_strip(void* __value, unsigned int __key) {
+  // On the stack the link register is protected with Pointer
+  // Authentication Code when compiled with -mbranch-protection.
+  // Let's stripping the PAC unconditionally because xpaclri is in
+  // the NOP space so will do nothing when it is not enabled or not available.
+  unsigned long ret;
+  asm volatile(
+      "mov x30, %1\n\t"
+      "hint #7\n\t"  // xpaclri
+      "mov %0, x30\n\t"
+      : "=r"(ret)
+      : "r"(__value)
+      : "x30");
+  return ret;
+}
+#define ptrauth_auth_data(__value, __old_key, __old_data) __value
+#define ptrauth_string_discriminator(__string) ((int)0)
  #else
  // Copied from <ptrauth.h>
  #define ptrauth_strip(__value, __key) __value
@@ -18,6 +36,6 @@
  #define ptrauth_string_discriminator(__string) ((int)0)
  #endif
  
-#define STRIP_PC(pc) ((uptr)ptrauth_strip(pc, 0))
+#define STRIP_PAC_PC(pc) ((uptr)ptrauth_strip(pc, 0))
  
  #endif // SANITIZER_PTRAUTH_H
diff --git a/libsanitizer/sanitizer_common/sanitizer_stackdepot.cpp b/libsanitizer/sanitizer_common/sanitizer_stackdepot.cpp
index 4692f50d323..44a95214e38 100644
--- a/libsanitizer/sanitizer_common/sanitizer_stackdepot.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_stackdepot.cpp
@@ -145,8 +145,7 @@ StackTrace StackDepotReverseMap::Get(u32 id) {
    if (!map_.size())
      return StackTrace();
    IdDescPair pair = {id, nullptr};
-  uptr idx =
-      InternalLowerBound(map_, 0, map_.size(), pair, IdDescPair::IdComparator);
+  uptr idx = InternalLowerBound(map_, pair, IdDescPair::IdComparator);
    if (idx > map_.size() || map_[idx].id != id)
      return StackTrace();
    return map_[idx].desc->load();
diff --git a/libsanitizer/sanitizer_common/sanitizer_stacktrace.cpp b/libsanitizer/sanitizer_common/sanitizer_stacktrace.cpp
index b28fc1cf736..07e4409f4a5 100644
--- a/libsanitizer/sanitizer_common/sanitizer_stacktrace.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_stacktrace.cpp
@@ -15,6 +15,7 @@
  #include "sanitizer_common.h"
  #include "sanitizer_flags.h"
  #include "sanitizer_platform.h"
+#include "sanitizer_ptrauth.h"
  
  namespace __sanitizer {
  
@@ -84,8 +85,8 @@ static inline uhwptr *GetCanonicFrame(uptr bp,
    // Nope, this does not look right either. This means the frame after next does
    // not have a valid frame pointer, but we can still extract the caller PC.
    // Unfortunately, there is no way to decide between GCC and LLVM frame
-  // layouts. Assume GCC.
-  return bp_prev - 1;
+  // layouts. Assume LLVM.
+  return bp_prev;
  #else
    return (uhwptr*)bp;
  #endif
@@ -108,28 +109,21 @@ void BufferedStackTrace::UnwindFast(uptr pc, uptr bp, uptr stack_top,
           IsAligned((uptr)frame, sizeof(*frame)) &&
           size < max_depth) {
  #ifdef __powerpc__
-    // PowerPC ABIs specify that the return address is saved on the
-    // *caller's* stack frame.  Thus we must dereference the back chain
-    // to find the caller frame before extracting it.
+    // PowerPC ABIs specify that the return address is saved at offset
+    // 16 of the *caller's* stack frame.  Thus we must dereference the
+    // back chain to find the caller frame before extracting it.
      uhwptr *caller_frame = (uhwptr*)frame[0];
      if (!IsValidFrame((uptr)caller_frame, stack_top, bottom) ||
          !IsAligned((uptr)caller_frame, sizeof(uhwptr)))
        break;
-    // For most ABIs the offset where the return address is saved is two
-    // register sizes.  The exception is the SVR4 ABI, which uses an
-    // offset of only one register size.
-#ifdef _CALL_SYSV
-    uhwptr pc1 = caller_frame[1];
-#else
      uhwptr pc1 = caller_frame[2];
-#endif
  #elif defined(__s390__)
      uhwptr pc1 = frame[14];
  #elif defined(__riscv)
      // frame[-1] contains the return address
      uhwptr pc1 = frame[-1];
  #else
-    uhwptr pc1 = frame[1];
+    uhwptr pc1 = STRIP_PAC_PC((void *)frame[1]);
  #endif
      // Let's assume that any pointer in the 0th page (i.e. <0x1000 on i386 and
      // x86_64) is invalid and stop unwinding here.  If we're adding support for
diff --git a/libsanitizer/sanitizer_common/sanitizer_stacktrace.h b/libsanitizer/sanitizer_common/sanitizer_stacktrace.h
index 0350fe84b04..15616f899d0 100644
--- a/libsanitizer/sanitizer_common/sanitizer_stacktrace.h
+++ b/libsanitizer/sanitizer_common/sanitizer_stacktrace.h
@@ -67,8 +67,6 @@ struct StackTrace {
    static uptr GetCurrentPc();
    static inline uptr GetPreviousInstructionPc(uptr pc);
    static uptr GetNextInstructionPc(uptr pc);
-  typedef bool (*SymbolizeCallback)(const void *pc, char *out_buffer,
-                                    int out_size);
  };
  
  // Performance-critical, must be in the header.
diff --git a/libsanitizer/sanitizer_common/sanitizer_stacktrace_libcdep.cpp b/libsanitizer/sanitizer_common/sanitizer_stacktrace_libcdep.cpp
index 7808ba9b0f5..738633209f0 100644
--- a/libsanitizer/sanitizer_common/sanitizer_stacktrace_libcdep.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_stacktrace_libcdep.cpp
@@ -23,8 +23,8 @@ void StackTrace::Print() const {
      Printf("    <empty stack>\n\n");
      return;
    }
-  InternalScopedString frame_desc(GetPageSizeCached() * 2);
-  InternalScopedString dedup_token(GetPageSizeCached());
+  InternalScopedString frame_desc;
+  InternalScopedString dedup_token;
    int dedup_frames = common_flags()->dedup_token_length;
    bool symbolize = RenderNeedsSymbolization(common_flags()->stack_trace_format);
    uptr frame_num = 0;
@@ -125,7 +125,7 @@ void __sanitizer_symbolize_pc(uptr pc, const char *fmt, char *out_buf,
      out_buf[out_buf_size - 1] = 0;
      return;
    }
-  InternalScopedString frame_desc(GetPageSizeCached());
+  InternalScopedString frame_desc;
    uptr frame_num = 0;
    // Reserve one byte for the final 0.
    char *out_end = out_buf + out_buf_size - 1;
@@ -156,7 +156,7 @@ void __sanitizer_symbolize_global(uptr data_addr, const char *fmt,
    out_buf[0] = 0;
    DataInfo DI;
    if (!Symbolizer::GetOrInit()->SymbolizeData(data_addr, &DI)) return;
-  InternalScopedString data_desc(GetPageSizeCached());
+  InternalScopedString data_desc;
    RenderData(&data_desc, fmt, &DI, common_flags()->strip_path_prefix);
    internal_strncpy(out_buf, data_desc.data(), out_buf_size);
    out_buf[out_buf_size - 1] = 0;
diff --git a/libsanitizer/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cpp b/libsanitizer/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cpp
index 0f1cadfeae3..53cfddcfbe0 100644
--- a/libsanitizer/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cpp
@@ -490,6 +490,9 @@ typedef user_regs_struct regs_struct;
  #ifndef NT_X86_XSTATE
  #define NT_X86_XSTATE 0x202
  #endif
+#ifndef PTRACE_GETREGSET
+#define PTRACE_GETREGSET 0x4204
+#endif
  // Compiler may use FP registers to store pointers.
  static constexpr uptr kExtraRegs[] = {NT_X86_XSTATE, NT_FPREGSET};
  
@@ -513,6 +516,8 @@ static constexpr uptr kExtraRegs[] = {0};
  
  #elif SANITIZER_RISCV64
  typedef struct user_regs_struct regs_struct;
+// sys/ucontext.h already defines REG_SP as 2. Undefine it first.
+#undef REG_SP
  #define REG_SP sp
  static constexpr uptr kExtraRegs[] = {0};
  #define ARCH_IOVEC_FOR_GETREGSET
diff --git a/libsanitizer/sanitizer_common/sanitizer_suppressions.cpp b/libsanitizer/sanitizer_common/sanitizer_suppressions.cpp
index 44c83a66c5f..a674034b8e2 100644
--- a/libsanitizer/sanitizer_common/sanitizer_suppressions.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_suppressions.cpp
@@ -34,7 +34,7 @@ SuppressionContext::SuppressionContext(const char *suppression_types[],
  static bool GetPathAssumingFileIsRelativeToExec(const char *file_path,
                                                  /*out*/char *new_file_path,
                                                  uptr new_file_path_size) {
-  InternalScopedString exec(kMaxPathLength);
+  InternalMmapVector<char> exec(kMaxPathLength);
    if (ReadBinaryNameCached(exec.data(), exec.size())) {
      const char *file_name_pos = StripModuleName(exec.data());
      uptr path_to_exec_len = file_name_pos - exec.data();
@@ -69,7 +69,7 @@ void SuppressionContext::ParseFromFile(const char *filename) {
    if (filename[0] == '\0')
      return;
  
-  InternalScopedString new_file_path(kMaxPathLength);
+  InternalMmapVector<char> new_file_path(kMaxPathLength);
    filename = FindFile(filename, new_file_path.data(), new_file_path.size());
  
    // Read the file.
diff --git a/libsanitizer/sanitizer_common/sanitizer_symbolizer_libcdep.cpp b/libsanitizer/sanitizer_common/sanitizer_symbolizer_libcdep.cpp
index 710da4c1cec..98418b426c3 100644
--- a/libsanitizer/sanitizer_common/sanitizer_symbolizer_libcdep.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_symbolizer_libcdep.cpp
@@ -356,7 +356,7 @@ void ParseSymbolizePCOutput(const char *str, SymbolizedStack *res) {
        InternalFree(info->function);
        info->function = 0;
      }
-    if (0 == internal_strcmp(info->file, "??")) {
+    if (info->file && 0 == internal_strcmp(info->file, "??")) {
        InternalFree(info->file);
        info->file = 0;
      }
diff --git a/libsanitizer/sanitizer_common/sanitizer_symbolizer_markup.cpp b/libsanitizer/sanitizer_common/sanitizer_symbolizer_markup.cpp
index 30cba08ed53..01edef9c1aa 100644
--- a/libsanitizer/sanitizer_common/sanitizer_symbolizer_markup.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_symbolizer_markup.cpp
@@ -54,6 +54,10 @@ bool Symbolizer::GetModuleNameAndOffsetForPC(uptr pc, const char **module_name,
    return false;
  }
  
+// This is mainly used by hwasan for online symbolization. This isn't needed
+// since hwasan can always just dump stack frames for offline symbolization.
+bool Symbolizer::SymbolizeFrame(uptr addr, FrameInfo *info) { return false; }
+
  // This is used in some places for suppression checking, which we
  // don't really support for Fuchsia.  It's also used in UBSan to
  // identify a PC location to a function name, so we always fill in
diff --git a/libsanitizer/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp b/libsanitizer/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
index 4dd5cc3ad7c..4cd4b4636f0 100644
--- a/libsanitizer/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
@@ -400,11 +400,20 @@ const char *Symbolizer::PlatformDemangle(const char *name) {
  
  static SymbolizerTool *ChooseExternalSymbolizer(LowLevelAllocator *allocator) {
    const char *path = common_flags()->external_symbolizer_path;
+
+  if (path && internal_strchr(path, '%')) {
+    char *new_path = (char *)InternalAlloc(kMaxPathLength);
+    SubstituteForFlagValue(path, new_path, kMaxPathLength);
+    path = new_path;
+  }
+
    const char *binary_name = path ? StripModuleName(path) : "";
+  static const char kLLVMSymbolizerPrefix[] = "llvm-symbolizer";
    if (path && path[0] == '\0') {
      VReport(2, "External symbolizer is explicitly disabled.\n");
      return nullptr;
-  } else if (!internal_strcmp(binary_name, "llvm-symbolizer")) {
+  } else if (!internal_strncmp(binary_name, kLLVMSymbolizerPrefix,
+                               internal_strlen(kLLVMSymbolizerPrefix))) {
      VReport(2, "Using llvm-symbolizer at user-specified path: %s\n", path);
      return new(*allocator) LLVMSymbolizer(path, allocator);
    } else if (!internal_strcmp(binary_name, "atos")) {
diff --git a/libsanitizer/sanitizer_common/sanitizer_symbolizer_report.cpp b/libsanitizer/sanitizer_common/sanitizer_symbolizer_report.cpp
index 06301b83ea1..9287993e665 100644
--- a/libsanitizer/sanitizer_common/sanitizer_symbolizer_report.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_symbolizer_report.cpp
@@ -31,7 +31,7 @@ namespace __sanitizer {
  void ReportErrorSummary(const char *error_type, const AddressInfo &info,
                          const char *alt_tool_name) {
    if (!common_flags()->print_summary) return;
-  InternalScopedString buff(kMaxSummaryLength);
+  InternalScopedString buff;
    buff.append("%s ", error_type);
    RenderFrame(&buff, "%L %F", 0, info.address, &info,
                common_flags()->symbolize_vs_style,
@@ -150,7 +150,7 @@ static void PrintMemoryByte(InternalScopedString *str, const char *before,
  static void MaybeDumpInstructionBytes(uptr pc) {
    if (!common_flags()->dump_instruction_bytes || (pc < GetPageSizeCached()))
      return;
-  InternalScopedString str(1024);
+  InternalScopedString str;
    str.append("First 16 instruction bytes at pc: ");
    if (IsAccessibleMemoryRange(pc, 16)) {
      for (int i = 0; i < 16; ++i) {
@@ -211,7 +211,7 @@ static void ReportDeadlySignalImpl(const SignalContext &sig, u32 tid,
      Report("The signal is caused by a %s memory access.\n", access_type);
      if (!sig.is_true_faulting_addr)
        Report("Hint: this fault was caused by a dereference of a high value "
-             "address (see register values below).  Dissassemble the provided "
+             "address (see register values below).  Disassemble the provided "
               "pc to learn which register was used.\n");
      else if (sig.addr < GetPageSizeCached())
        Report("Hint: address points to the zero page.\n");
diff --git a/libsanitizer/sanitizer_common/sanitizer_symbolizer_win.cpp b/libsanitizer/sanitizer_common/sanitizer_symbolizer_win.cpp
index 48fa2d1033a..702d901353d 100644
--- a/libsanitizer/sanitizer_common/sanitizer_symbolizer_win.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_symbolizer_win.cpp
@@ -136,9 +136,10 @@ void InitializeDbgHelpIfNeeded() {
  bool WinSymbolizerTool::SymbolizePC(uptr addr, SymbolizedStack *frame) {
    InitializeDbgHelpIfNeeded();
  
-  // See http://msdn.microsoft.com/en-us/library/ms680578(VS.85).aspx
-  char buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME * sizeof(CHAR)];
-  PSYMBOL_INFO symbol = (PSYMBOL_INFO)buffer;
+  // See https://docs.microsoft.com/en-us/windows/win32/debug/retrieving-symbol-information-by-address
+  InternalMmapVector<char> buffer(sizeof(SYMBOL_INFO) +
+                                  MAX_SYM_NAME * sizeof(CHAR));
+  PSYMBOL_INFO symbol = (PSYMBOL_INFO)&buffer[0];
    symbol->SizeOfStruct = sizeof(SYMBOL_INFO);
    symbol->MaxNameLen = MAX_SYM_NAME;
    DWORD64 offset = 0;
@@ -223,7 +224,7 @@ bool SymbolizerProcess::StartSymbolizerSubprocess() {
    // Compute the command line. Wrap double quotes around everything.
    const char *argv[kArgVMax];
    GetArgV(path_, argv);
-  InternalScopedString command_line(kMaxPathLength * 3);
+  InternalScopedString command_line;
    for (int i = 0; argv[i]; i++) {
      const char *arg = argv[i];
      int arglen = internal_strlen(arg);
@@ -281,8 +282,15 @@ static void ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> *list,
      return;
    }
  
-  // Add llvm-symbolizer in case the binary has dwarf.
+  // Add llvm-symbolizer.
    const char *user_path = common_flags()->external_symbolizer_path;
+
+  if (user_path && internal_strchr(user_path, '%')) {
+    char *new_path = (char *)InternalAlloc(kMaxPathLength);
+    SubstituteForFlagValue(user_path, new_path, kMaxPathLength);
+    user_path = new_path;
+  }
+
    const char *path =
        user_path ? user_path : FindPathToBinary("llvm-symbolizer.exe");
    if (path) {
diff --git a/libsanitizer/sanitizer_common/sanitizer_termination.cpp b/libsanitizer/sanitizer_common/sanitizer_termination.cpp
index 84be6fc3234..6a54734353c 100644
--- a/libsanitizer/sanitizer_common/sanitizer_termination.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_termination.cpp
@@ -59,26 +59,31 @@ void NORETURN Die() {
    internal__exit(common_flags()->exitcode);
  }
  
-static CheckFailedCallbackType CheckFailedCallback;
-void SetCheckFailedCallback(CheckFailedCallbackType callback) {
-  CheckFailedCallback = callback;
+static void (*CheckUnwindCallback)();
+void SetCheckUnwindCallback(void (*callback)()) {
+  CheckUnwindCallback = callback;
  }
  
-const int kSecondsToSleepWhenRecursiveCheckFailed = 2;
-
  void NORETURN CheckFailed(const char *file, int line, const char *cond,
                            u64 v1, u64 v2) {
-  static atomic_uint32_t num_calls;
-  if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) > 10) {
-    SleepForSeconds(kSecondsToSleepWhenRecursiveCheckFailed);
+  u32 tid = GetTid();
+  Printf("%s: CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx) (tid=%u)\n",
+         SanitizerToolName, StripModuleName(file), line, cond, (uptr)v1,
+         (uptr)v2, tid);
+  static atomic_uint32_t first_tid;
+  u32 cmp = 0;
+  if (!atomic_compare_exchange_strong(&first_tid, &cmp, tid,
+                                      memory_order_relaxed)) {
+    if (cmp == tid) {
+      // Recursing into CheckFailed.
+    } else {
+      // Another thread fails already, let it print the stack and terminate.
+      SleepForSeconds(2);
+    }
      Trap();
    }
-
-  if (CheckFailedCallback) {
-    CheckFailedCallback(file, line, cond, v1, v2);
-  }
-  Report("Sanitizer CHECK failed: %s:%d %s (%lld, %lld)\n", file, line, cond,
-                                                            v1, v2);
+  if (CheckUnwindCallback)
+    CheckUnwindCallback();
    Die();
  }
  
diff --git a/libsanitizer/sanitizer_common/sanitizer_thread_registry.cpp b/libsanitizer/sanitizer_common/sanitizer_thread_registry.cpp
index f2c6f279931..3273da38bfd 100644
--- a/libsanitizer/sanitizer_common/sanitizer_thread_registry.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_thread_registry.cpp
@@ -85,7 +85,7 @@ void ThreadContextBase::SetCreated(uptr _user_id, u64 _unique_id,
    unique_id = _unique_id;
    detached = _detached;
    // Parent tid makes no sense for the main thread.
-  if (tid != 0)
+  if (tid != kMainTid)
      parent_tid = _parent_tid;
    OnCreated(arg);
  }
@@ -99,8 +99,6 @@ void ThreadContextBase::Reset() {
  
  // ThreadRegistry implementation.
  
-const u32 ThreadRegistry::kUnknownTid = ~0U;
-
  ThreadRegistry::ThreadRegistry(ThreadContextFactory factory, u32 max_threads,
                                 u32 thread_quarantine_size, u32 max_reuse)
      : context_factory_(factory),
@@ -135,7 +133,7 @@ uptr ThreadRegistry::GetMaxAliveThreads() {
  u32 ThreadRegistry::CreateThread(uptr user_id, bool detached, u32 parent_tid,
                                   void *arg) {
    BlockingMutexLock l(&mtx_);
-  u32 tid = kUnknownTid;
+  u32 tid = kInvalidTid;
    ThreadContextBase *tctx = QuarantinePop();
    if (tctx) {
      tid = tctx->tid;
@@ -155,7 +153,7 @@ u32 ThreadRegistry::CreateThread(uptr user_id, bool detached, u32 parent_tid,
      Die();
    }
    CHECK_NE(tctx, 0);
-  CHECK_NE(tid, kUnknownTid);
+  CHECK_NE(tid, kInvalidTid);
    CHECK_LT(tid, max_threads_);
    CHECK_EQ(tctx->status, ThreadStatusInvalid);
    alive_threads_++;
@@ -186,7 +184,7 @@ u32 ThreadRegistry::FindThread(FindThreadCallback cb, void *arg) {
      if (tctx != 0 && cb(tctx, arg))
        return tctx->tid;
    }
-  return kUnknownTid;
+  return kInvalidTid;
  }
  
  ThreadContextBase *
@@ -278,7 +276,7 @@ void ThreadRegistry::JoinThread(u32 tid, void *arg) {
  // really started.  We just did CreateThread for a prospective new
  // thread before trying to create it, and then failed to actually
  // create it, and so never called StartThread.
-void ThreadRegistry::FinishThread(u32 tid) {
+ThreadStatus ThreadRegistry::FinishThread(u32 tid) {
    BlockingMutexLock l(&mtx_);
    CHECK_GT(alive_threads_, 0);
    alive_threads_--;
@@ -286,6 +284,7 @@ void ThreadRegistry::FinishThread(u32 tid) {
    ThreadContextBase *tctx = threads_[tid];
    CHECK_NE(tctx, 0);
    bool dead = tctx->detached;
+  ThreadStatus prev_status = tctx->status;
    if (tctx->status == ThreadStatusRunning) {
      CHECK_GT(running_threads_, 0);
      running_threads_--;
@@ -300,6 +299,7 @@ void ThreadRegistry::FinishThread(u32 tid) {
      QuarantinePush(tctx);
    }
    tctx->SetDestroyed();
+  return prev_status;
  }
  
  void ThreadRegistry::StartThread(u32 tid, tid_t os_id, ThreadType thread_type,
diff --git a/libsanitizer/sanitizer_common/sanitizer_thread_registry.h b/libsanitizer/sanitizer_common/sanitizer_thread_registry.h
index 85c522a31ca..dcd445c28ae 100644
--- a/libsanitizer/sanitizer_common/sanitizer_thread_registry.h
+++ b/libsanitizer/sanitizer_common/sanitizer_thread_registry.h
@@ -87,8 +87,6 @@ typedef ThreadContextBase* (*ThreadContextFactory)(u32 tid);
  
  class ThreadRegistry {
   public:
-  static const u32 kUnknownTid;
-
    ThreadRegistry(ThreadContextFactory factory, u32 max_threads,
                   u32 thread_quarantine_size, u32 max_reuse = 0);
    void GetNumberOfThreads(uptr *total = nullptr, uptr *running = nullptr,
@@ -113,7 +111,7 @@ class ThreadRegistry {
    void RunCallbackForEachThreadLocked(ThreadCallback cb, void *arg);
  
    typedef bool (*FindThreadCallback)(ThreadContextBase *tctx, void *arg);
-  // Finds a thread using the provided callback. Returns kUnknownTid if no
+  // Finds a thread using the provided callback. Returns kInvalidTid if no
    // thread is found.
    u32 FindThread(FindThreadCallback cb, void *arg);
    // Should be guarded by ThreadRegistryLock. Return 0 if no thread
@@ -126,7 +124,8 @@ class ThreadRegistry {
    void SetThreadNameByUserId(uptr user_id, const char *name);
    void DetachThread(u32 tid, void *arg);
    void JoinThread(u32 tid, void *arg);
-  void FinishThread(u32 tid);
+  // Finishes thread and returns previous status.
+  ThreadStatus FinishThread(u32 tid);
    void StartThread(u32 tid, tid_t os_id, ThreadType thread_type, void *arg);
    void SetThreadUserId(u32 tid, uptr user_id);
  
diff --git a/libsanitizer/sanitizer_common/sanitizer_tls_get_addr.cpp b/libsanitizer/sanitizer_common/sanitizer_tls_get_addr.cpp
index 10748f96420..1f664b6cf5b 100644
--- a/libsanitizer/sanitizer_common/sanitizer_tls_get_addr.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_tls_get_addr.cpp
@@ -12,6 +12,7 @@
  
  #include "sanitizer_tls_get_addr.h"
  
+#include "sanitizer_atomic.h"
  #include "sanitizer_flags.h"
  #include "sanitizer_platform_interceptors.h"
  
@@ -42,39 +43,54 @@ static atomic_uintptr_t number_of_live_dtls;
  
  static const uptr kDestroyedThread = -1;
  
-static inline void DTLS_Deallocate(DTLS::DTV *dtv, uptr size) {
-  if (!size) return;
-  VReport(2, "__tls_get_addr: DTLS_Deallocate %p %zd\n", dtv, size);
-  UnmapOrDie(dtv, size * sizeof(DTLS::DTV));
+static void DTLS_Deallocate(DTLS::DTVBlock *block) {
+  VReport(2, "__tls_get_addr: DTLS_Deallocate %p %zd\n", block);
+  UnmapOrDie(block, sizeof(DTLS::DTVBlock));
    atomic_fetch_sub(&number_of_live_dtls, 1, memory_order_relaxed);
  }
  
-static inline void DTLS_Resize(uptr new_size) {
-  if (dtls.dtv_size >= new_size) return;
-  new_size = RoundUpToPowerOfTwo(new_size);
-  new_size = Max(new_size, 4096UL / sizeof(DTLS::DTV));
-  DTLS::DTV *new_dtv =
-      (DTLS::DTV *)MmapOrDie(new_size * sizeof(DTLS::DTV), "DTLS_Resize");
+static DTLS::DTVBlock *DTLS_NextBlock(atomic_uintptr_t *cur) {
+  uptr v = atomic_load(cur, memory_order_acquire);
+  if (v == kDestroyedThread)
+    return nullptr;
+  DTLS::DTVBlock *next = (DTLS::DTVBlock *)v;
+  if (next)
+    return next;
+  DTLS::DTVBlock *new_dtv =
+      (DTLS::DTVBlock *)MmapOrDie(sizeof(DTLS::DTVBlock), "DTLS_NextBlock");
+  uptr prev = 0;
+  if (!atomic_compare_exchange_strong(cur, &prev, (uptr)new_dtv,
+                                      memory_order_seq_cst)) {
+    UnmapOrDie(new_dtv, sizeof(DTLS::DTVBlock));
+    return (DTLS::DTVBlock *)prev;
+  }
    uptr num_live_dtls =
        atomic_fetch_add(&number_of_live_dtls, 1, memory_order_relaxed);
-  VReport(2, "__tls_get_addr: DTLS_Resize %p %zd\n", &dtls, num_live_dtls);
-  CHECK_LT(num_live_dtls, 1 << 20);
-  uptr old_dtv_size = dtls.dtv_size;
-  DTLS::DTV *old_dtv = dtls.dtv;
-  if (old_dtv_size)
-    internal_memcpy(new_dtv, dtls.dtv, dtls.dtv_size * sizeof(DTLS::DTV));
-  dtls.dtv = new_dtv;
-  dtls.dtv_size = new_size;
-  if (old_dtv_size)
-    DTLS_Deallocate(old_dtv, old_dtv_size);
+  VReport(2, "__tls_get_addr: DTLS_NextBlock %p %zd\n", &dtls, num_live_dtls);
+  return new_dtv;
+}
+
+static DTLS::DTV *DTLS_Find(uptr id) {
+  VReport(2, "__tls_get_addr: DTLS_Find %p %zd\n", &dtls, id);
+  static constexpr uptr kPerBlock = ARRAY_SIZE(DTLS::DTVBlock::dtvs);
+  DTLS::DTVBlock *cur = DTLS_NextBlock(&dtls.dtv_block);
+  if (!cur)
+    return nullptr;
+  for (; id >= kPerBlock; id -= kPerBlock) cur = DTLS_NextBlock(&cur->next);
+  return cur->dtvs + id;
  }
  
  void DTLS_Destroy() {
    if (!common_flags()->intercept_tls_get_addr) return;
-  VReport(2, "__tls_get_addr: DTLS_Destroy %p %zd\n", &dtls, dtls.dtv_size);
-  uptr s = dtls.dtv_size;
-  dtls.dtv_size = kDestroyedThread;  // Do this before unmap for AS-safety.
-  DTLS_Deallocate(dtls.dtv, s);
+  VReport(2, "__tls_get_addr: DTLS_Destroy %p\n", &dtls);
+  DTLS::DTVBlock *block = (DTLS::DTVBlock *)atomic_exchange(
+      &dtls.dtv_block, kDestroyedThread, memory_order_release);
+  while (block) {
+    DTLS::DTVBlock *next =
+        (DTLS::DTVBlock *)atomic_load(&block->next, memory_order_acquire);
+    DTLS_Deallocate(block);
+    block = next;
+  }
  }
  
  #if defined(__powerpc64__) || defined(__mips__)
@@ -96,9 +112,9 @@ DTLS::DTV *DTLS_on_tls_get_addr(void *arg_void, void *res,
    if (!common_flags()->intercept_tls_get_addr) return 0;
    TlsGetAddrParam *arg = reinterpret_cast<TlsGetAddrParam *>(arg_void);
    uptr dso_id = arg->dso_id;
-  if (dtls.dtv_size == kDestroyedThread) return 0;
-  DTLS_Resize(dso_id + 1);
-  if (dtls.dtv[dso_id].beg) return 0;
+  DTLS::DTV *dtv = DTLS_Find(dso_id);
+  if (!dtv || dtv->beg)
+    return 0;
    uptr tls_size = 0;
    uptr tls_beg = reinterpret_cast<uptr>(res) - arg->offset - kDtvOffset;
    VReport(2, "__tls_get_addr: %p {%p,%p} => %p; tls_beg: %p; sp: %p "
@@ -126,9 +142,9 @@ DTLS::DTV *DTLS_on_tls_get_addr(void *arg_void, void *res,
      // This may happen inside the DTOR of main thread, so just ignore it.
      tls_size = 0;
    }
-  dtls.dtv[dso_id].beg = tls_beg;
-  dtls.dtv[dso_id].size = tls_size;
-  return dtls.dtv + dso_id;
+  dtv->beg = tls_beg;
+  dtv->size = tls_size;
+  return dtv;
  }
  
  void DTLS_on_libc_memalign(void *ptr, uptr size) {
@@ -141,7 +157,8 @@ void DTLS_on_libc_memalign(void *ptr, uptr size) {
  DTLS *DTLS_Get() { return &dtls; }
  
  bool DTLSInDestruction(DTLS *dtls) {
-  return dtls->dtv_size == kDestroyedThread;
+  return atomic_load(&dtls->dtv_block, memory_order_relaxed) ==
+         kDestroyedThread;
  }
  
  #else
diff --git a/libsanitizer/sanitizer_common/sanitizer_tls_get_addr.h b/libsanitizer/sanitizer_common/sanitizer_tls_get_addr.h
index c7cd5a8bffc..a599c0bbc75 100644
--- a/libsanitizer/sanitizer_common/sanitizer_tls_get_addr.h
+++ b/libsanitizer/sanitizer_common/sanitizer_tls_get_addr.h
@@ -28,6 +28,7 @@
  #ifndef SANITIZER_TLS_GET_ADDR_H
  #define SANITIZER_TLS_GET_ADDR_H
  
+#include "sanitizer_atomic.h"
  #include "sanitizer_common.h"
  
  namespace __sanitizer {
@@ -38,15 +39,31 @@ struct DTLS {
    struct DTV {
      uptr beg, size;
    };
+  struct DTVBlock {
+    atomic_uintptr_t next;
+    DTV dtvs[(4096UL - sizeof(next)) / sizeof(DTLS::DTV)];
+  };
+
+  static_assert(sizeof(DTVBlock) <= 4096UL, "Unexpected block size");
  
-  uptr dtv_size;
-  DTV *dtv;  // dtv_size elements, allocated by MmapOrDie.
+  atomic_uintptr_t dtv_block;
  
    // Auxiliary fields, don't access them outside sanitizer_tls_get_addr.cpp
    uptr last_memalign_size;
    uptr last_memalign_ptr;
  };
  
+template <typename Fn>
+void ForEachDVT(DTLS *dtls, const Fn &fn) {
+  DTLS::DTVBlock *block =
+      (DTLS::DTVBlock *)atomic_load(&dtls->dtv_block, memory_order_acquire);
+  while (block) {
+    int id = 0;
+    for (auto &d : block->dtvs) fn(d, id++);
+    block = (DTLS::DTVBlock *)atomic_load(&block->next, memory_order_acquire);
+  }
+}
+
  // Returns pointer and size of a linker-allocated TLS block.
  // Each block is returned exactly once.
  DTLS::DTV *DTLS_on_tls_get_addr(void *arg, void *res, uptr static_tls_begin,
diff --git a/libsanitizer/sanitizer_common/sanitizer_unwind_win.cpp b/libsanitizer/sanitizer_common/sanitizer_unwind_win.cpp
index e2edf428004..7e01c81d042 100644
--- a/libsanitizer/sanitizer_common/sanitizer_unwind_win.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_unwind_win.cpp
@@ -43,6 +43,10 @@ void BufferedStackTrace::UnwindSlow(uptr pc, u32 max_depth) {
    trace_buffer[0] = pc;
  }
  
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wframe-larger-than="
+#endif
  void BufferedStackTrace::UnwindSlow(uptr pc, void *context, u32 max_depth) {
    CHECK(context);
    CHECK_GE(max_depth, 2);
@@ -74,6 +78,9 @@ void BufferedStackTrace::UnwindSlow(uptr pc, void *context, u32 max_depth) {
      trace_buffer[size++] = (uptr)stack_frame.AddrPC.Offset;
    }
  }
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
  #endif  // #if !SANITIZER_GO
  
  #endif  // SANITIZER_WINDOWS
diff --git a/libsanitizer/sanitizer_common/sanitizer_win.cpp b/libsanitizer/sanitizer_common/sanitizer_win.cpp
index 85ac2633bde..f383e130fa5 100644
--- a/libsanitizer/sanitizer_common/sanitizer_win.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_win.cpp
@@ -334,8 +334,12 @@ bool MprotectNoAccess(uptr addr, uptr size) {
  }
  
  void ReleaseMemoryPagesToOS(uptr beg, uptr end) {
-  // This is almost useless on 32-bits.
-  // FIXME: add madvise-analog when we move to 64-bits.
+  uptr beg_aligned = RoundDownTo(beg, GetPageSizeCached()),
+       end_aligned = RoundDownTo(end, GetPageSizeCached());
+  CHECK(beg < end);                // make sure the region is sane
+  if (beg_aligned == end_aligned)  // make sure we're freeing at least 1 page;
+    return;
+  UnmapOrDie((void *)beg, end_aligned - beg_aligned);
  }
  
  void SetShadowRegionHugePageMode(uptr addr, uptr size) {
@@ -386,6 +390,12 @@ uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
    return 0;
  }
  
+uptr MapDynamicShadowAndAliases(uptr shadow_size, uptr alias_size,
+                                uptr num_aliases, uptr ring_buffer_size) {
+  CHECK(false && "HWASan aliasing is unimplemented on Windows");
+  return 0;
+}
+
  bool MemoryRangeIsAvailable(uptr range_start, uptr range_end) {
    MEMORY_BASIC_INFORMATION mbi;
    CHECK(VirtualQuery((void *)range_start, &mbi, sizeof(mbi)));
@@ -564,7 +574,7 @@ void Abort() {
  // load the image at this address. Therefore, we call it the preferred base. Any
  // addresses in the DWARF typically assume that the object has been loaded at
  // this address.
-static uptr GetPreferredBase(const char *modname) {
+static uptr GetPreferredBase(const char *modname, char *buf, size_t buf_size) {
    fd_t fd = OpenFile(modname, RdOnly, nullptr);
    if (fd == kInvalidFd)
      return 0;
@@ -586,12 +596,10 @@ static uptr GetPreferredBase(const char *modname) {
    // IMAGE_FILE_HEADER
    // IMAGE_OPTIONAL_HEADER
    // Seek to e_lfanew and read all that data.
-  char buf[4 + sizeof(IMAGE_FILE_HEADER) + sizeof(IMAGE_OPTIONAL_HEADER)];
    if (::SetFilePointer(fd, dos_header.e_lfanew, nullptr, FILE_BEGIN) ==
        INVALID_SET_FILE_POINTER)
      return 0;
-  if (!ReadFromFile(fd, &buf[0], sizeof(buf), &bytes_read) ||
-      bytes_read != sizeof(buf))
+  if (!ReadFromFile(fd, buf, buf_size, &bytes_read) || bytes_read != buf_size)
      return 0;
  
    // Check for "PE\0\0" before the PE header.
@@ -633,6 +641,10 @@ void ListOfModules::init() {
      }
    }
  
+  InternalMmapVector<char> buf(4 + sizeof(IMAGE_FILE_HEADER) +
+                               sizeof(IMAGE_OPTIONAL_HEADER));
+  InternalMmapVector<wchar_t> modname_utf16(kMaxPathLength);
+  InternalMmapVector<char> module_name(kMaxPathLength);
    // |num_modules| is the number of modules actually present,
    size_t num_modules = bytes_required / sizeof(HMODULE);
    for (size_t i = 0; i < num_modules; ++i) {
@@ -642,15 +654,13 @@ void ListOfModules::init() {
        continue;
  
      // Get the UTF-16 path and convert to UTF-8.
-    wchar_t modname_utf16[kMaxPathLength];
      int modname_utf16_len =
-        GetModuleFileNameW(handle, modname_utf16, kMaxPathLength);
+        GetModuleFileNameW(handle, &modname_utf16[0], kMaxPathLength);
      if (modname_utf16_len == 0)
        modname_utf16[0] = '\0';
-    char module_name[kMaxPathLength];
-    int module_name_len =
-        ::WideCharToMultiByte(CP_UTF8, 0, modname_utf16, modname_utf16_len + 1,
-                              &module_name[0], kMaxPathLength, NULL, NULL);
+    int module_name_len = ::WideCharToMultiByte(
+        CP_UTF8, 0, &modname_utf16[0], modname_utf16_len + 1, &module_name[0],
+        kMaxPathLength, NULL, NULL);
      module_name[module_name_len] = '\0';
  
      uptr base_address = (uptr)mi.lpBaseOfDll;
@@ -660,15 +670,16 @@ void ListOfModules::init() {
      // RVA when computing the module offset. This helps llvm-symbolizer find the
      // right DWARF CU. In the common case that the image is loaded at it's
      // preferred address, we will now print normal virtual addresses.
-    uptr preferred_base = GetPreferredBase(&module_name[0]);
+    uptr preferred_base =
+        GetPreferredBase(&module_name[0], &buf[0], buf.size());
      uptr adjusted_base = base_address - preferred_base;
  
-    LoadedModule cur_module;
-    cur_module.set(module_name, adjusted_base);
+    modules_.push_back(LoadedModule());
+    LoadedModule &cur_module = modules_.back();
+    cur_module.set(&module_name[0], adjusted_base);
      // We add the whole module as one single address range.
      cur_module.addAddressRange(base_address, end_address, /*executable*/ true,
                                 /*writable*/ true);
-    modules_.push_back(cur_module);
    }
    UnmapOrDie(hmodules, modules_buffer_size);
  }
@@ -956,22 +967,27 @@ void SignalContext::InitPcSpBp() {
  
  uptr SignalContext::GetAddress() const {
    EXCEPTION_RECORD *exception_record = (EXCEPTION_RECORD *)siginfo;
-  return exception_record->ExceptionInformation[1];
+  if (exception_record->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
+    return exception_record->ExceptionInformation[1];
+  return (uptr)exception_record->ExceptionAddress;
  }
  
  bool SignalContext::IsMemoryAccess() const {
-  return GetWriteFlag() != SignalContext::UNKNOWN;
+  return ((EXCEPTION_RECORD *)siginfo)->ExceptionCode ==
+         EXCEPTION_ACCESS_VIOLATION;
  }
  
-bool SignalContext::IsTrueFaultingAddress() const {
-  // FIXME: Provide real implementation for this. See Linux and Mac variants.
-  return IsMemoryAccess();
-}
+bool SignalContext::IsTrueFaultingAddress() const { return true; }
  
  SignalContext::WriteFlag SignalContext::GetWriteFlag() const {
    EXCEPTION_RECORD *exception_record = (EXCEPTION_RECORD *)siginfo;
+
+  // The write flag is only available for access violation exceptions.
+  if (exception_record->ExceptionCode != EXCEPTION_ACCESS_VIOLATION)
+    return SignalContext::UNKNOWN;
+
    // The contents of this array are documented at
-  // https://msdn.microsoft.com/en-us/library/windows/desktop/aa363082(v=vs.85).aspx
+  // https://docs.microsoft.com/en-us/windows/win32/api/winnt/ns-winnt-exception_record
    // The first element indicates read as 0, write as 1, or execute as 8.  The
    // second element is the faulting address.
    switch (exception_record->ExceptionInformation[0]) {
@@ -1037,10 +1053,24 @@ const char *SignalContext::Describe() const {
  }
  
  uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
-  // FIXME: Actually implement this function.
-  CHECK_GT(buf_len, 0);
-  buf[0] = 0;
-  return 0;
+  if (buf_len == 0)
+    return 0;
+
+  // Get the UTF-16 path and convert to UTF-8.
+  InternalMmapVector<wchar_t> binname_utf16(kMaxPathLength);
+  int binname_utf16_len =
+      GetModuleFileNameW(NULL, &binname_utf16[0], kMaxPathLength);
+  if (binname_utf16_len == 0) {
+    buf[0] = '\0';
+    return 0;
+  }
+  int binary_name_len =
+      ::WideCharToMultiByte(CP_UTF8, 0, &binname_utf16[0], binname_utf16_len,
+                            buf, buf_len, NULL, NULL);
+  if ((unsigned)binary_name_len == buf_len)
+    --binary_name_len;
+  buf[binary_name_len] = '\0';
+  return binary_name_len;
  }
  
  uptr ReadLongProcessName(/*out*/char *buf, uptr buf_len) {
diff --git a/libsanitizer/tsan/tsan_clock.cpp b/libsanitizer/tsan/tsan_clock.cpp
index c91b29cb22b..8e5188392ca 100644
--- a/libsanitizer/tsan/tsan_clock.cpp
+++ b/libsanitizer/tsan/tsan_clock.cpp
@@ -150,7 +150,7 @@ void ThreadClock::acquire(ClockCache *c, SyncClock *src) {
    bool acquired = false;
    for (unsigned i = 0; i < kDirtyTids; i++) {
      SyncClock::Dirty dirty = src->dirty_[i];
-    unsigned tid = dirty.tid;
+    unsigned tid = dirty.tid();
      if (tid != kInvalidTid) {
        if (clk_[tid] < dirty.epoch) {
          clk_[tid] = dirty.epoch;
@@ -299,10 +299,10 @@ void ThreadClock::ReleaseStore(ClockCache *c, SyncClock *dst) {
      dst->tab_idx_ = cached_idx_;
      dst->size_ = cached_size_;
      dst->blocks_ = cached_blocks_;
-    CHECK_EQ(dst->dirty_[0].tid, kInvalidTid);
+    CHECK_EQ(dst->dirty_[0].tid(), kInvalidTid);
      // The cached clock is shared (immutable),
      // so this is where we store the current clock.
-    dst->dirty_[0].tid = tid_;
+    dst->dirty_[0].set_tid(tid_);
      dst->dirty_[0].epoch = clk_[tid_];
      dst->release_store_tid_ = tid_;
      dst->release_store_reused_ = reused_;
@@ -336,8 +336,7 @@ void ThreadClock::ReleaseStore(ClockCache *c, SyncClock *dst) {
      ce.reused = 0;
      i++;
    }
-  for (uptr i = 0; i < kDirtyTids; i++)
-    dst->dirty_[i].tid = kInvalidTid;
+  for (uptr i = 0; i < kDirtyTids; i++) dst->dirty_[i].set_tid(kInvalidTid);
    dst->release_store_tid_ = tid_;
    dst->release_store_reused_ = reused_;
    // Rememeber that we don't need to acquire it in future.
@@ -369,10 +368,10 @@ void ThreadClock::UpdateCurrentThread(ClockCache *c, SyncClock *dst) const {
    // Update the threads time, but preserve 'acquired' flag.
    for (unsigned i = 0; i < kDirtyTids; i++) {
      SyncClock::Dirty *dirty = &dst->dirty_[i];
-    const unsigned tid = dirty->tid;
+    const unsigned tid = dirty->tid();
      if (tid == tid_ || tid == kInvalidTid) {
        CPP_STAT_INC(StatClockReleaseFast);
-      dirty->tid = tid_;
+      dirty->set_tid(tid_);
        dirty->epoch = clk_[tid_];
        return;
      }
@@ -393,8 +392,8 @@ bool ThreadClock::IsAlreadyAcquired(const SyncClock *src) const {
      return false;
    for (unsigned i = 0; i < kDirtyTids; i++) {
      SyncClock::Dirty dirty = src->dirty_[i];
-    if (dirty.tid != kInvalidTid) {
-      if (clk_[dirty.tid] < dirty.epoch)
+    if (dirty.tid() != kInvalidTid) {
+      if (clk_[dirty.tid()] < dirty.epoch)
          return false;
      }
    }
@@ -453,8 +452,7 @@ void SyncClock::ResetImpl() {
    blocks_ = 0;
    release_store_tid_ = kInvalidTid;
    release_store_reused_ = 0;
-  for (uptr i = 0; i < kDirtyTids; i++)
-    dirty_[i].tid = kInvalidTid;
+  for (uptr i = 0; i < kDirtyTids; i++) dirty_[i].set_tid(kInvalidTid);
  }
  
  void SyncClock::Resize(ClockCache *c, uptr nclk) {
@@ -503,10 +501,10 @@ void SyncClock::Resize(ClockCache *c, uptr nclk) {
  void SyncClock::FlushDirty() {
    for (unsigned i = 0; i < kDirtyTids; i++) {
      Dirty *dirty = &dirty_[i];
-    if (dirty->tid != kInvalidTid) {
-      CHECK_LT(dirty->tid, size_);
-      elem(dirty->tid).epoch = dirty->epoch;
-      dirty->tid = kInvalidTid;
+    if (dirty->tid() != kInvalidTid) {
+      CHECK_LT(dirty->tid(), size_);
+      elem(dirty->tid()).epoch = dirty->epoch;
+      dirty->set_tid(kInvalidTid);
      }
    }
  }
@@ -559,7 +557,7 @@ ALWAYS_INLINE bool SyncClock::Cachable() const {
    if (size_ == 0)
      return false;
    for (unsigned i = 0; i < kDirtyTids; i++) {
-    if (dirty_[i].tid != kInvalidTid)
+    if (dirty_[i].tid() != kInvalidTid)
        return false;
    }
    return atomic_load_relaxed(ref_ptr(tab_)) == 1;
@@ -606,7 +604,7 @@ ALWAYS_INLINE void SyncClock::append_block(u32 idx) {
  u64 SyncClock::get(unsigned tid) const {
    for (unsigned i = 0; i < kDirtyTids; i++) {
      Dirty dirty = dirty_[i];
-    if (dirty.tid == tid)
+    if (dirty.tid() == tid)
        return dirty.epoch;
    }
    return elem(tid).epoch;
@@ -625,9 +623,8 @@ void SyncClock::DebugDump(int(*printf)(const char *s, ...)) {
    for (uptr i = 0; i < size_; i++)
      printf("%s%llu", i == 0 ? "" : ",", elem(i).reused);
    printf("] release_store_tid=%d/%d dirty_tids=%d[%llu]/%d[%llu]",
-      release_store_tid_, release_store_reused_,
-      dirty_[0].tid, dirty_[0].epoch,
-      dirty_[1].tid, dirty_[1].epoch);
+         release_store_tid_, release_store_reused_, dirty_[0].tid(),
+         dirty_[0].epoch, dirty_[1].tid(), dirty_[1].epoch);
  }
  
  void SyncClock::Iter::Next() {
diff --git a/libsanitizer/tsan/tsan_clock.h b/libsanitizer/tsan/tsan_clock.h
index 736cdae06ba..31376a1bc9e 100644
--- a/libsanitizer/tsan/tsan_clock.h
+++ b/libsanitizer/tsan/tsan_clock.h
@@ -17,7 +17,7 @@
  
  namespace __tsan {
  
-typedef DenseSlabAlloc<ClockBlock, 1<<16, 1<<10> ClockAlloc;
+typedef DenseSlabAlloc<ClockBlock, 1 << 22, 1 << 10> ClockAlloc;
  typedef DenseSlabAllocCache ClockCache;
  
  // The clock that lives in sync variables (mutexes, atomics, etc).
@@ -65,10 +65,20 @@ class SyncClock {
    static const uptr kDirtyTids = 2;
  
    struct Dirty {
-    u64 epoch  : kClkBits;
-    u64 tid : 64 - kClkBits;  // kInvalidId if not active
+    u32 tid() const { return tid_ == kShortInvalidTid ? kInvalidTid : tid_; }
+    void set_tid(u32 tid) {
+      tid_ = tid == kInvalidTid ? kShortInvalidTid : tid;
+    }
+    u64 epoch : kClkBits;
+
+   private:
+    // Full kInvalidTid won't fit into Dirty::tid.
+    static const u64 kShortInvalidTid = (1ull << (64 - kClkBits)) - 1;
+    u64 tid_ : 64 - kClkBits;  // kInvalidId if not active
    };
  
+  static_assert(sizeof(Dirty) == 8, "Dirty is not 64bit");
+
    unsigned release_store_tid_;
    unsigned release_store_reused_;
    Dirty dirty_[kDirtyTids];
diff --git a/libsanitizer/tsan/tsan_defs.h b/libsanitizer/tsan/tsan_defs.h
index 293d7deccc3..f53787aeba9 100644
--- a/libsanitizer/tsan/tsan_defs.h
+++ b/libsanitizer/tsan/tsan_defs.h
@@ -98,8 +98,6 @@ const bool kCollectHistory = false;
  const bool kCollectHistory = true;
  #endif
  
-const u16 kInvalidTid = kMaxTid + 1;
-
  // The following "build consistency" machinery ensures that all source files
  // are built in the same configuration. Inconsistent builds lead to
  // hard to debug crashes.
diff --git a/libsanitizer/tsan/tsan_dense_alloc.h b/libsanitizer/tsan/tsan_dense_alloc.h
index 64fc50e95c2..6c89e405980 100644
--- a/libsanitizer/tsan/tsan_dense_alloc.h
+++ b/libsanitizer/tsan/tsan_dense_alloc.h
@@ -29,28 +29,40 @@ class DenseSlabAllocCache {
    typedef u32 IndexT;
    uptr pos;
    IndexT cache[kSize];
-  template<typename T, uptr kL1Size, uptr kL2Size> friend class DenseSlabAlloc;
+  template <typename, uptr, uptr, u64>
+  friend class DenseSlabAlloc;
  };
  
-template<typename T, uptr kL1Size, uptr kL2Size>
+template <typename T, uptr kL1Size, uptr kL2Size, u64 kReserved = 0>
  class DenseSlabAlloc {
   public:
    typedef DenseSlabAllocCache Cache;
    typedef typename Cache::IndexT IndexT;
  
-  explicit DenseSlabAlloc(const char *name) {
-    // Check that kL1Size and kL2Size are sane.
-    CHECK_EQ(kL1Size & (kL1Size - 1), 0);
-    CHECK_EQ(kL2Size & (kL2Size - 1), 0);
-    CHECK_GE(1ull << (sizeof(IndexT) * 8), kL1Size * kL2Size);
-    // Check that it makes sense to use the dense alloc.
-    CHECK_GE(sizeof(T), sizeof(IndexT));
-    internal_memset(map_, 0, sizeof(map_));
+  static_assert((kL1Size & (kL1Size - 1)) == 0,
+                "kL1Size must be a power-of-two");
+  static_assert((kL2Size & (kL2Size - 1)) == 0,
+                "kL2Size must be a power-of-two");
+  static_assert((kL1Size * kL2Size) <= (1ull << (sizeof(IndexT) * 8)),
+                "kL1Size/kL2Size are too large");
+  static_assert(((kL1Size * kL2Size - 1) & kReserved) == 0,
+                "reserved bits don't fit");
+  static_assert(sizeof(T) > sizeof(IndexT),
+                "it doesn't make sense to use dense alloc");
+
+  explicit DenseSlabAlloc(LinkerInitialized, const char *name) {
      freelist_ = 0;
      fillpos_ = 0;
      name_ = name;
    }
  
+  explicit DenseSlabAlloc(const char *name)
+      : DenseSlabAlloc(LINKER_INITIALIZED, name) {
+    // It can be very large.
+    // Don't page it in for linker initialized objects.
+    internal_memset(map_, 0, sizeof(map_));
+  }
+
    ~DenseSlabAlloc() {
      for (uptr i = 0; i < kL1Size; i++) {
        if (map_[i] != 0)
diff --git a/libsanitizer/tsan/tsan_external.cpp b/libsanitizer/tsan/tsan_external.cpp
index 466b2bf0f66..a87e12f2936 100644
--- a/libsanitizer/tsan/tsan_external.cpp
+++ b/libsanitizer/tsan/tsan_external.cpp
@@ -111,12 +111,12 @@ void __tsan_external_assign_tag(void *addr, void *tag) {
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void __tsan_external_read(void *addr, void *caller_pc, void *tag) {
-  ExternalAccess(addr, STRIP_PC(caller_pc), tag, MemoryRead);
+  ExternalAccess(addr, STRIP_PAC_PC(caller_pc), tag, MemoryRead);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  void __tsan_external_write(void *addr, void *caller_pc, void *tag) {
-  ExternalAccess(addr, STRIP_PC(caller_pc), tag, MemoryWrite);
+  ExternalAccess(addr, STRIP_PAC_PC(caller_pc), tag, MemoryWrite);
  }
  }  // extern "C"
  
diff --git a/libsanitizer/tsan/tsan_interceptors_mac.cpp b/libsanitizer/tsan/tsan_interceptors_mac.cpp
index aa29536d861..ed10fccc980 100644
--- a/libsanitizer/tsan/tsan_interceptors_mac.cpp
+++ b/libsanitizer/tsan/tsan_interceptors_mac.cpp
@@ -438,6 +438,7 @@ struct fake_shared_weak_count {
    virtual void on_zero_shared() = 0;
    virtual void _unused_0x18() = 0;
    virtual void on_zero_shared_weak() = 0;
+  virtual ~fake_shared_weak_count() = 0;  // suppress -Wnon-virtual-dtor
  };
  }  // namespace
  
diff --git a/libsanitizer/tsan/tsan_interceptors_posix.cpp b/libsanitizer/tsan/tsan_interceptors_posix.cpp
index aa04d8dfb67..2651e22c39f 100644
--- a/libsanitizer/tsan/tsan_interceptors_posix.cpp
+++ b/libsanitizer/tsan/tsan_interceptors_posix.cpp
@@ -54,10 +54,6 @@ using namespace __tsan;
  #define vfork __vfork14
  #endif
  
-#if SANITIZER_ANDROID
-#define mallopt(a, b)
-#endif
-
  #ifdef __mips__
  const int kSigCount = 129;
  #else
@@ -85,6 +81,8 @@ extern "C" int pthread_attr_init(void *attr);
  extern "C" int pthread_attr_destroy(void *attr);
  DECLARE_REAL(int, pthread_attr_getdetachstate, void *, void *)
  extern "C" int pthread_attr_setstacksize(void *attr, uptr stacksize);
+extern "C" int pthread_atfork(void (*prepare)(void), void (*parent)(void),
+                              void (*child)(void));
  extern "C" int pthread_key_create(unsigned *key, void (*destructor)(void* v));
  extern "C" int pthread_setspecific(unsigned key, const void *v);
  DECLARE_REAL(int, pthread_mutexattr_gettype, void *, void *)
@@ -97,7 +95,7 @@ extern "C" void _exit(int status);
  extern "C" int fileno_unlocked(void *stream);
  extern "C" int dirfd(void *dirp);
  #endif
-#if !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_NETBSD
+#if SANITIZER_GLIBC
  extern "C" int mallopt(int param, int value);
  #endif
  #if SANITIZER_NETBSD
@@ -659,8 +657,11 @@ TSAN_INTERCEPTOR(void*, malloc, uptr size) {
    return p;
  }
  
+// In glibc<2.25, dynamic TLS blocks are allocated by __libc_memalign. Intercept
+// __libc_memalign so that (1) we can detect races (2) free will not be called
+// on libc internally allocated blocks.
  TSAN_INTERCEPTOR(void*, __libc_memalign, uptr align, uptr sz) {
-  SCOPED_TSAN_INTERCEPTOR(__libc_memalign, align, sz);
+  SCOPED_INTERCEPTOR_RAW(__libc_memalign, align, sz);
    return user_memalign(thr, pc, align, sz);
  }
  
@@ -773,6 +774,11 @@ static void *mmap_interceptor(ThreadState *thr, uptr pc, Mmap real_mmap,
    if (!fix_mmap_addr(&addr, sz, flags)) return MAP_FAILED;
    void *res = real_mmap(addr, sz, prot, flags, fd, off);
    if (res != MAP_FAILED) {
+    if (!IsAppMem((uptr)res) || !IsAppMem((uptr)res + sz - 1)) {
+      Report("ThreadSanitizer: mmap at bad address: addr=%p size=%p res=%p\n",
+             addr, (void*)sz, res);
+      Die();
+    }
      if (fd > 0) FdAccess(thr, pc, fd);
      MemoryRangeImitateWriteOrResetRange(thr, pc, (uptr)res, sz);
    }
@@ -1122,27 +1128,37 @@ static void *init_cond(void *c, bool force = false) {
    return (void*)cond;
  }
  
+namespace {
+
+template <class Fn>
  struct CondMutexUnlockCtx {
    ScopedInterceptor *si;
    ThreadState *thr;
    uptr pc;
    void *m;
+  void *c;
+  const Fn &fn;
+
+  int Cancel() const { return fn(); }
+  void Unlock() const;
  };
  
-static void cond_mutex_unlock(CondMutexUnlockCtx *arg) {
+template <class Fn>
+void CondMutexUnlockCtx<Fn>::Unlock() const {
    // pthread_cond_wait interceptor has enabled async signal delivery
    // (see BlockingCall below). Disable async signals since we are running
    // tsan code. Also ScopedInterceptor and BlockingCall destructors won't run
    // since the thread is cancelled, so we have to manually execute them
    // (the thread still can run some user code due to pthread_cleanup_push).
-  ThreadSignalContext *ctx = SigCtx(arg->thr);
+  ThreadSignalContext *ctx = SigCtx(thr);
    CHECK_EQ(atomic_load(&ctx->in_blocking_func, memory_order_relaxed), 1);
    atomic_store(&ctx->in_blocking_func, 0, memory_order_relaxed);
-  MutexPostLock(arg->thr, arg->pc, (uptr)arg->m, MutexFlagDoPreLockOnPostLock);
+  MutexPostLock(thr, pc, (uptr)m, MutexFlagDoPreLockOnPostLock);
    // Undo BlockingCall ctor effects.
-  arg->thr->ignore_interceptors--;
-  arg->si->~ScopedInterceptor();
+  thr->ignore_interceptors--;
+  si->~ScopedInterceptor();
  }
+}  // namespace
  
  INTERCEPTOR(int, pthread_cond_init, void *c, void *a) {
    void *cond = init_cond(c, true);
@@ -1151,20 +1167,24 @@ INTERCEPTOR(int, pthread_cond_init, void *c, void *a) {
    return REAL(pthread_cond_init)(cond, a);
  }
  
-static int cond_wait(ThreadState *thr, uptr pc, ScopedInterceptor *si,
-                     int (*fn)(void *c, void *m, void *abstime), void *c,
-                     void *m, void *t) {
+template <class Fn>
+int cond_wait(ThreadState *thr, uptr pc, ScopedInterceptor *si, const Fn &fn,
+              void *c, void *m) {
    MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
    MutexUnlock(thr, pc, (uptr)m);
-  CondMutexUnlockCtx arg = {si, thr, pc, m};
    int res = 0;
    // This ensures that we handle mutex lock even in case of pthread_cancel.
    // See test/tsan/cond_cancel.cpp.
    {
      // Enable signal delivery while the thread is blocked.
      BlockingCall bc(thr);
+    CondMutexUnlockCtx<Fn> arg = {si, thr, pc, m, c, fn};
      res = call_pthread_cancel_with_cleanup(
-        fn, c, m, t, (void (*)(void *arg))cond_mutex_unlock, &arg);
+        [](void *arg) -> int {
+          return ((const CondMutexUnlockCtx<Fn> *)arg)->Cancel();
+        },
+        [](void *arg) { ((const CondMutexUnlockCtx<Fn> *)arg)->Unlock(); },
+        &arg);
    }
    if (res == errno_EOWNERDEAD) MutexRepair(thr, pc, (uptr)m);
    MutexPostLock(thr, pc, (uptr)m, MutexFlagDoPreLockOnPostLock);
@@ -1174,25 +1194,46 @@ static int cond_wait(ThreadState *thr, uptr pc, ScopedInterceptor *si,
  INTERCEPTOR(int, pthread_cond_wait, void *c, void *m) {
    void *cond = init_cond(c);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_wait, cond, m);
-  return cond_wait(thr, pc, &si, (int (*)(void *c, void *m, void *abstime))REAL(
-                                     pthread_cond_wait),
-                   cond, m, 0);
+  return cond_wait(
+      thr, pc, &si, [=]() { return REAL(pthread_cond_wait)(cond, m); }, cond,
+      m);
  }
  
  INTERCEPTOR(int, pthread_cond_timedwait, void *c, void *m, void *abstime) {
    void *cond = init_cond(c);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_timedwait, cond, m, abstime);
-  return cond_wait(thr, pc, &si, REAL(pthread_cond_timedwait), cond, m,
-                   abstime);
+  return cond_wait(
+      thr, pc, &si,
+      [=]() { return REAL(pthread_cond_timedwait)(cond, m, abstime); }, cond,
+      m);
  }
  
+#if SANITIZER_LINUX
+INTERCEPTOR(int, pthread_cond_clockwait, void *c, void *m,
+            __sanitizer_clockid_t clock, void *abstime) {
+  void *cond = init_cond(c);
+  SCOPED_TSAN_INTERCEPTOR(pthread_cond_clockwait, cond, m, clock, abstime);
+  return cond_wait(
+      thr, pc, &si,
+      [=]() { return REAL(pthread_cond_clockwait)(cond, m, clock, abstime); },
+      cond, m);
+}
+#define TSAN_MAYBE_PTHREAD_COND_CLOCKWAIT TSAN_INTERCEPT(pthread_cond_clockwait)
+#else
+#define TSAN_MAYBE_PTHREAD_COND_CLOCKWAIT
+#endif
+
  #if SANITIZER_MAC
  INTERCEPTOR(int, pthread_cond_timedwait_relative_np, void *c, void *m,
              void *reltime) {
    void *cond = init_cond(c);
    SCOPED_TSAN_INTERCEPTOR(pthread_cond_timedwait_relative_np, cond, m, reltime);
-  return cond_wait(thr, pc, &si, REAL(pthread_cond_timedwait_relative_np), cond,
-                   m, reltime);
+  return cond_wait(
+      thr, pc, &si,
+      [=]() {
+        return REAL(pthread_cond_timedwait_relative_np)(cond, m, reltime);
+      },
+      cond, m);
  }
  #endif
  
@@ -1937,7 +1978,8 @@ static void CallUserSignalHandler(ThreadState *thr, bool sync, bool acquire,
    // because in async signal processing case (when handler is called directly
    // from rtl_generic_sighandler) we have not yet received the reraised
    // signal; and it looks too fragile to intercept all ways to reraise a signal.
-  if (flags()->report_bugs && !sync && sig != SIGTERM && errno != 99) {
+  if (ShouldReport(thr, ReportTypeErrnoInSignal) && !sync && sig != SIGTERM &&
+      errno != 99) {
      VarSizeStackTrace stack;
      // StackTrace::GetNestInstructionPc(pc) is used because return address is
      // expected, OutputReport() will undo this.
@@ -2107,26 +2149,32 @@ TSAN_INTERCEPTOR(int, fork, int fake) {
    if (in_symbolizer())
      return REAL(fork)(fake);
    SCOPED_INTERCEPTOR_RAW(fork, fake);
+  return REAL(fork)(fake);
+}
+
+void atfork_prepare() {
+  if (in_symbolizer())
+    return;
+  ThreadState *thr = cur_thread();
+  const uptr pc = StackTrace::GetCurrentPc();
    ForkBefore(thr, pc);
-  int pid;
-  {
-    // On OS X, REAL(fork) can call intercepted functions (OSSpinLockLock), and
-    // we'll assert in CheckNoLocks() unless we ignore interceptors.
-    ScopedIgnoreInterceptors ignore;
-    pid = REAL(fork)(fake);
-  }
-  if (pid == 0) {
-    // child
-    ForkChildAfter(thr, pc);
-    FdOnFork(thr, pc);
-  } else if (pid > 0) {
-    // parent
-    ForkParentAfter(thr, pc);
-  } else {
-    // error
-    ForkParentAfter(thr, pc);
-  }
-  return pid;
+}
+
+void atfork_parent() {
+  if (in_symbolizer())
+    return;
+  ThreadState *thr = cur_thread();
+  const uptr pc = StackTrace::GetCurrentPc();
+  ForkParentAfter(thr, pc);
+}
+
+void atfork_child() {
+  if (in_symbolizer())
+    return;
+  ThreadState *thr = cur_thread();
+  const uptr pc = StackTrace::GetCurrentPc();
+  ForkChildAfter(thr, pc);
+  FdOnFork(thr, pc);
  }
  
  TSAN_INTERCEPTOR(int, vfork, int fake) {
@@ -2479,13 +2527,10 @@ static USED void syscall_fd_release(uptr pc, int fd) {
    FdRelease(thr, pc, fd);
  }
  
-static void syscall_pre_fork(uptr pc) {
-  TSAN_SYSCALL();
-  ForkBefore(thr, pc);
-}
+static void syscall_pre_fork(uptr pc) { ForkBefore(cur_thread(), pc); }
  
  static void syscall_post_fork(uptr pc, int pid) {
-  TSAN_SYSCALL();
+  ThreadState *thr = cur_thread();
    if (pid == 0) {
      // child
      ForkChildAfter(thr, pc);
@@ -2635,7 +2680,7 @@ void InitializeInterceptors() {
  #endif
  
    // Instruct libc malloc to consume less memory.
-#if SANITIZER_LINUX
+#if SANITIZER_GLIBC
    mallopt(1, 0);  // M_MXFAST
    mallopt(-3, 32*1024);  // M_MMAP_THRESHOLD
  #endif
@@ -2698,6 +2743,8 @@ void InitializeInterceptors() {
    TSAN_INTERCEPT_VER(pthread_cond_timedwait, PTHREAD_ABI_BASE);
    TSAN_INTERCEPT_VER(pthread_cond_destroy, PTHREAD_ABI_BASE);
  
+  TSAN_MAYBE_PTHREAD_COND_CLOCKWAIT;
+
    TSAN_INTERCEPT(pthread_mutex_init);
    TSAN_INTERCEPT(pthread_mutex_destroy);
    TSAN_INTERCEPT(pthread_mutex_trylock);
@@ -2799,6 +2846,10 @@ void InitializeInterceptors() {
      Printf("ThreadSanitizer: failed to setup atexit callback\n");
      Die();
    }
+  if (pthread_atfork(atfork_prepare, atfork_parent, atfork_child)) {
+    Printf("ThreadSanitizer: failed to setup atfork callbacks\n");
+    Die();
+  }
  
  #if !SANITIZER_MAC && !SANITIZER_NETBSD && !SANITIZER_FREEBSD
    if (pthread_key_create(&interceptor_ctx()->finalize_key, &thread_finalize)) {
diff --git a/libsanitizer/tsan/tsan_interface.cpp b/libsanitizer/tsan/tsan_interface.cpp
index 55f1c9834f7..9bd0e8580b1 100644
--- a/libsanitizer/tsan/tsan_interface.cpp
+++ b/libsanitizer/tsan/tsan_interface.cpp
@@ -40,13 +40,13 @@ void __tsan_write16(void *addr) {
  }
  
  void __tsan_read16_pc(void *addr, void *pc) {
-  MemoryRead(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog8);
-  MemoryRead(cur_thread(), STRIP_PC(pc), (uptr)addr + 8, kSizeLog8);
+  MemoryRead(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog8);
+  MemoryRead(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr + 8, kSizeLog8);
  }
  
  void __tsan_write16_pc(void *addr, void *pc) {
-  MemoryWrite(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog8);
-  MemoryWrite(cur_thread(), STRIP_PC(pc), (uptr)addr + 8, kSizeLog8);
+  MemoryWrite(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog8);
+  MemoryWrite(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr + 8, kSizeLog8);
  }
  
  // __tsan_unaligned_read/write calls are emitted by compiler.
diff --git a/libsanitizer/tsan/tsan_interface.h b/libsanitizer/tsan/tsan_interface.h
index 6d7286ca5b8..6e022b56850 100644
--- a/libsanitizer/tsan/tsan_interface.h
+++ b/libsanitizer/tsan/tsan_interface.h
@@ -204,7 +204,7 @@ __extension__ typedef __int128 a128;
  #endif
  
  // Part of ABI, do not change.
-// https://github.com/llvm/llvm-project/blob/master/libcxx/include/atomic
+// https://github.com/llvm/llvm-project/blob/main/libcxx/include/atomic
  typedef enum {
    mo_relaxed,
    mo_consume,
@@ -415,6 +415,13 @@ void __tsan_go_atomic32_compare_exchange(ThreadState *thr, uptr cpc, uptr pc,
  SANITIZER_INTERFACE_ATTRIBUTE
  void __tsan_go_atomic64_compare_exchange(ThreadState *thr, uptr cpc, uptr pc,
                                           u8 *a);
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_on_initialize();
+
+SANITIZER_INTERFACE_ATTRIBUTE
+int __tsan_on_finalize(int failed);
+
  }  // extern "C"
  
  }  // namespace __tsan
diff --git a/libsanitizer/tsan/tsan_interface_inl.h b/libsanitizer/tsan/tsan_interface_inl.h
index f5d743c1077..5e77d4d3d28 100644
--- a/libsanitizer/tsan/tsan_interface_inl.h
+++ b/libsanitizer/tsan/tsan_interface_inl.h
@@ -51,35 +51,35 @@ void __tsan_write8(void *addr) {
  }
  
  void __tsan_read1_pc(void *addr, void *pc) {
-  MemoryRead(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog1);
+  MemoryRead(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog1);
  }
  
  void __tsan_read2_pc(void *addr, void *pc) {
-  MemoryRead(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog2);
+  MemoryRead(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog2);
  }
  
  void __tsan_read4_pc(void *addr, void *pc) {
-  MemoryRead(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog4);
+  MemoryRead(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog4);
  }
  
  void __tsan_read8_pc(void *addr, void *pc) {
-  MemoryRead(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog8);
+  MemoryRead(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog8);
  }
  
  void __tsan_write1_pc(void *addr, void *pc) {
-  MemoryWrite(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog1);
+  MemoryWrite(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog1);
  }
  
  void __tsan_write2_pc(void *addr, void *pc) {
-  MemoryWrite(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog2);
+  MemoryWrite(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog2);
  }
  
  void __tsan_write4_pc(void *addr, void *pc) {
-  MemoryWrite(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog4);
+  MemoryWrite(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog4);
  }
  
  void __tsan_write8_pc(void *addr, void *pc) {
-  MemoryWrite(cur_thread(), STRIP_PC(pc), (uptr)addr, kSizeLog8);
+  MemoryWrite(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, kSizeLog8);
  }
  
  void __tsan_vptr_update(void **vptr_p, void *new_val) {
@@ -101,7 +101,7 @@ void __tsan_vptr_read(void **vptr_p) {
  }
  
  void __tsan_func_entry(void *pc) {
-  FuncEntry(cur_thread(), STRIP_PC(pc));
+  FuncEntry(cur_thread(), STRIP_PAC_PC(pc));
  }
  
  void __tsan_func_exit() {
@@ -125,9 +125,9 @@ void __tsan_write_range(void *addr, uptr size) {
  }
  
  void __tsan_read_range_pc(void *addr, uptr size, void *pc) {
-  MemoryAccessRange(cur_thread(), STRIP_PC(pc), (uptr)addr, size, false);
+  MemoryAccessRange(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, size, false);
  }
  
  void __tsan_write_range_pc(void *addr, uptr size, void *pc) {
-  MemoryAccessRange(cur_thread(), STRIP_PC(pc), (uptr)addr, size, true);
+  MemoryAccessRange(cur_thread(), STRIP_PAC_PC(pc), (uptr)addr, size, true);
  }
diff --git a/libsanitizer/tsan/tsan_mman.cpp b/libsanitizer/tsan/tsan_mman.cpp
index 743e67bf2f7..45a39f0f8ec 100644
--- a/libsanitizer/tsan/tsan_mman.cpp
+++ b/libsanitizer/tsan/tsan_mman.cpp
@@ -145,7 +145,7 @@ void AllocatorPrintStats() {
  
  static void SignalUnsafeCall(ThreadState *thr, uptr pc) {
    if (atomic_load_relaxed(&thr->in_signal_handler) == 0 ||
-      !flags()->report_signal_unsafe)
+      !ShouldReport(thr, ReportTypeSignalUnsafe))
      return;
    VarSizeStackTrace stack;
    ObtainCurrentStack(thr, pc, &stack);
diff --git a/libsanitizer/tsan/tsan_platform.h b/libsanitizer/tsan/tsan_platform.h
index 16169cab666..101522d8fa4 100644
--- a/libsanitizer/tsan/tsan_platform.h
+++ b/libsanitizer/tsan/tsan_platform.h
@@ -23,9 +23,21 @@
  
  namespace __tsan {
  
+#if defined(__x86_64__)
+#define HAS_48_BIT_ADDRESS_SPACE 1
+#elif SANITIZER_IOSSIM // arm64 iOS simulators (order of #if matters)
+#define HAS_48_BIT_ADDRESS_SPACE 1
+#elif SANITIZER_IOS // arm64 iOS devices (order of #if matters)
+#define HAS_48_BIT_ADDRESS_SPACE 0
+#elif SANITIZER_MAC // arm64 macOS (order of #if matters)
+#define HAS_48_BIT_ADDRESS_SPACE 1
+#else
+#define HAS_48_BIT_ADDRESS_SPACE 0
+#endif
+
  #if !SANITIZER_GO
  
-#if defined(__x86_64__)
+#if HAS_48_BIT_ADDRESS_SPACE
  /*
  C/C++ on linux/x86_64 and freebsd/x86_64
  0000 0000 1000 - 0080 0000 0000: main binary and/or MAP_32BIT mappings (512GB)
@@ -93,7 +105,7 @@ fe00 0000 00 - ff00 0000 00: heap                                        (4 GB)
  ff00 0000 00 - ff80 0000 00: -                                           (2 GB)
  ff80 0000 00 - ffff ffff ff: modules and main thread stack              (<2 GB)
  */
-struct Mapping {
+struct Mapping40 {
    static const uptr kMetaShadowBeg = 0x4000000000ull;
    static const uptr kMetaShadowEnd = 0x5000000000ull;
    static const uptr kTraceMemBeg   = 0xb000000000ull;
@@ -114,6 +126,7 @@ struct Mapping {
  };
  
  #define TSAN_MID_APP_RANGE 1
+#define TSAN_RUNTIME_VMA 1
  #elif defined(__aarch64__) && defined(__APPLE__)
  /*
  C/C++ on Darwin/iOS/ARM64 (36-bit VMA, 64 GB VM)
@@ -146,7 +159,7 @@ struct Mapping {
    static const uptr kVdsoBeg       = 0x7000000000000000ull;
  };
  
-#elif defined(__aarch64__)
+#elif defined(__aarch64__) && !defined(__APPLE__)
  // AArch64 supports multiple VMA which leads to multiple address transformation
  // functions.  To support these multiple VMAS transformations and mappings TSAN
  // runtime for AArch64 uses an external memory read (vmaSize) to select which
@@ -354,7 +367,7 @@ struct Mapping47 {
  #define TSAN_RUNTIME_VMA 1
  #endif
  
-#elif SANITIZER_GO && !SANITIZER_WINDOWS && defined(__x86_64__)
+#elif SANITIZER_GO && !SANITIZER_WINDOWS && HAS_48_BIT_ADDRESS_SPACE
  
  /* Go on linux, darwin and freebsd on x86_64
  0000 0000 1000 - 0000 1000 0000: executable
@@ -502,7 +515,7 @@ Go on linux/mips64 (47-bit VMA)
  6000 0000 0000 - 6200 0000 0000: traces
  6200 0000 0000 - 8000 0000 0000: -
  */
-struct Mapping {
+struct Mapping47 {
    static const uptr kMetaShadowBeg = 0x300000000000ull;
    static const uptr kMetaShadowEnd = 0x400000000000ull;
    static const uptr kTraceMemBeg = 0x600000000000ull;
@@ -512,6 +525,9 @@ struct Mapping {
    static const uptr kAppMemBeg = 0x000000001000ull;
    static const uptr kAppMemEnd = 0x00e000000000ull;
  };
+
+#define TSAN_RUNTIME_VMA 1
+
  #else
  # error "Unknown platform"
  #endif
@@ -592,6 +608,16 @@ uptr MappingArchImpl(void) {
    }
    DCHECK(0);
    return 0;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return MappingImpl<Mapping40, Type>();
+#else
+    case 47: return MappingImpl<Mapping47, Type>();
+#endif
+  }
+  DCHECK(0);
+  return 0;
  #else
    return MappingImpl<Mapping, Type>();
  #endif
@@ -749,6 +775,16 @@ bool IsAppMem(uptr mem) {
    }
    DCHECK(0);
    return false;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return IsAppMemImpl<Mapping40>(mem);
+#else
+    case 47: return IsAppMemImpl<Mapping47>(mem);
+#endif
+  }
+  DCHECK(0);
+  return false;
  #else
    return IsAppMemImpl<Mapping>(mem);
  #endif
@@ -780,6 +816,16 @@ bool IsShadowMem(uptr mem) {
    }
    DCHECK(0);
    return false;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return IsShadowMemImpl<Mapping40>(mem);
+#else
+    case 47: return IsShadowMemImpl<Mapping47>(mem);
+#endif
+  }
+  DCHECK(0);
+  return false;
  #else
    return IsShadowMemImpl<Mapping>(mem);
  #endif
@@ -811,6 +857,16 @@ bool IsMetaMem(uptr mem) {
    }
    DCHECK(0);
    return false;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return IsMetaMemImpl<Mapping40>(mem);
+#else
+    case 47: return IsMetaMemImpl<Mapping47>(mem);
+#endif
+  }
+  DCHECK(0);
+  return false;
  #else
    return IsMetaMemImpl<Mapping>(mem);
  #endif
@@ -852,6 +908,16 @@ uptr MemToShadow(uptr x) {
    }
    DCHECK(0);
    return 0;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return MemToShadowImpl<Mapping40>(x);
+#else
+    case 47: return MemToShadowImpl<Mapping47>(x);
+#endif
+  }
+  DCHECK(0);
+  return 0;
  #else
    return MemToShadowImpl<Mapping>(x);
  #endif
@@ -895,6 +961,16 @@ u32 *MemToMeta(uptr x) {
    }
    DCHECK(0);
    return 0;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return MemToMetaImpl<Mapping40>(x);
+#else
+    case 47: return MemToMetaImpl<Mapping47>(x);
+#endif
+  }
+  DCHECK(0);
+  return 0;
  #else
    return MemToMetaImpl<Mapping>(x);
  #endif
@@ -951,6 +1027,16 @@ uptr ShadowToMem(uptr s) {
    }
    DCHECK(0);
    return 0;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return ShadowToMemImpl<Mapping40>(s);
+#else
+    case 47: return ShadowToMemImpl<Mapping47>(s);
+#endif
+  }
+  DCHECK(0);
+  return 0;
  #else
    return ShadowToMemImpl<Mapping>(s);
  #endif
@@ -990,6 +1076,16 @@ uptr GetThreadTrace(int tid) {
    }
    DCHECK(0);
    return 0;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return GetThreadTraceImpl<Mapping40>(tid);
+#else
+    case 47: return GetThreadTraceImpl<Mapping47>(tid);
+#endif
+  }
+  DCHECK(0);
+  return 0;
  #else
    return GetThreadTraceImpl<Mapping>(tid);
  #endif
@@ -1024,6 +1120,16 @@ uptr GetThreadTraceHeader(int tid) {
    }
    DCHECK(0);
    return 0;
+#elif defined(__mips64)
+  switch (vmaSize) {
+#if !SANITIZER_GO
+    case 40: return GetThreadTraceHeaderImpl<Mapping40>(tid);
+#else
+    case 47: return GetThreadTraceHeaderImpl<Mapping47>(tid);
+#endif
+  }
+  DCHECK(0);
+  return 0;
  #else
    return GetThreadTraceHeaderImpl<Mapping>(tid);
  #endif
@@ -1040,9 +1146,8 @@ int ExtractRecvmsgFDs(void *msg, int *fds, int nfd);
  uptr ExtractLongJmpSp(uptr *env);
  void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size);
  
-int call_pthread_cancel_with_cleanup(int(*fn)(void *c, void *m,
-    void *abstime), void *c, void *m, void *abstime,
-    void(*cleanup)(void *arg), void *arg);
+int call_pthread_cancel_with_cleanup(int (*fn)(void *arg),
+                                     void (*cleanup)(void *arg), void *arg);
  
  void DestroyThreadState();
  void PlatformCleanUpThreadState(ThreadState *thr);
diff --git a/libsanitizer/tsan/tsan_platform_linux.cpp b/libsanitizer/tsan/tsan_platform_linux.cpp
index d136dcb1cec..e5b6690edfd 100644
--- a/libsanitizer/tsan/tsan_platform_linux.cpp
+++ b/libsanitizer/tsan/tsan_platform_linux.cpp
@@ -250,6 +250,20 @@ void InitializePlatformEarly() {
      Die();
    }
  # endif
+#elif defined(__mips64)
+# if !SANITIZER_GO
+  if (vmaSize != 40) {
+    Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
+    Printf("FATAL: Found %zd - Supported 40\n", vmaSize);
+    Die();
+  }
+# else
+  if (vmaSize != 47) {
+    Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
+    Printf("FATAL: Found %zd - Supported 47\n", vmaSize);
+    Die();
+  }
+# endif
  #endif
  #endif
  }
@@ -443,14 +457,13 @@ void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size) {
  
  // Note: this function runs with async signals enabled,
  // so it must not touch any tsan state.
-int call_pthread_cancel_with_cleanup(int(*fn)(void *c, void *m,
-    void *abstime), void *c, void *m, void *abstime,
-    void(*cleanup)(void *arg), void *arg) {
+int call_pthread_cancel_with_cleanup(int (*fn)(void *arg),
+                                     void (*cleanup)(void *arg), void *arg) {
    // pthread_cleanup_push/pop are hardcore macros mess.
    // We can't intercept nor call them w/o including pthread.h.
    int res;
    pthread_cleanup_push(cleanup, arg);
-  res = fn(c, m, abstime);
+  res = fn(arg);
    pthread_cleanup_pop(0);
    return res;
  }
@@ -484,7 +497,7 @@ ThreadState *cur_thread() {
          dead_thread_state->fast_state.SetIgnoreBit();
          dead_thread_state->ignore_interceptors = 1;
          dead_thread_state->is_dead = true;
-        *const_cast<int*>(&dead_thread_state->tid) = -1;
+        *const_cast<u32*>(&dead_thread_state->tid) = -1;
          CHECK_EQ(0, internal_mprotect(dead_thread_state, sizeof(ThreadState),
                                        PROT_READ));
        }
diff --git a/libsanitizer/tsan/tsan_platform_mac.cpp b/libsanitizer/tsan/tsan_platform_mac.cpp
index ec2c5fb1621..d9719a136b2 100644
--- a/libsanitizer/tsan/tsan_platform_mac.cpp
+++ b/libsanitizer/tsan/tsan_platform_mac.cpp
@@ -234,7 +234,7 @@ static void my_pthread_introspection_hook(unsigned int event, pthread_t thread,
  #endif
  
  void InitializePlatformEarly() {
-#if !SANITIZER_GO && defined(__aarch64__)
+#if !SANITIZER_GO && !HAS_48_BIT_ADDRESS_SPACE
    uptr max_vm = GetMaxUserVirtualAddress() + 1;
    if (max_vm != Mapping::kHiAppMemEnd) {
      Printf("ThreadSanitizer: unsupported vm address limit %p, expected %p.\n",
@@ -306,14 +306,13 @@ void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size) {
  #if !SANITIZER_GO
  // Note: this function runs with async signals enabled,
  // so it must not touch any tsan state.
-int call_pthread_cancel_with_cleanup(int(*fn)(void *c, void *m,
-    void *abstime), void *c, void *m, void *abstime,
-    void(*cleanup)(void *arg), void *arg) {
+int call_pthread_cancel_with_cleanup(int (*fn)(void *arg),
+                                     void (*cleanup)(void *arg), void *arg) {
    // pthread_cleanup_push/pop are hardcore macros mess.
    // We can't intercept nor call them w/o including pthread.h.
    int res;
    pthread_cleanup_push(cleanup, arg);
-  res = fn(c, m, abstime);
+  res = fn(arg);
    pthread_cleanup_pop(0);
    return res;
  }
diff --git a/libsanitizer/tsan/tsan_platform_posix.cpp b/libsanitizer/tsan/tsan_platform_posix.cpp
index d56b6c3b9c5..73e1d4577c2 100644
--- a/libsanitizer/tsan/tsan_platform_posix.cpp
+++ b/libsanitizer/tsan/tsan_platform_posix.cpp
@@ -99,7 +99,7 @@ void CheckAndProtect() {
      Die();
    }
  
-#if defined(__aarch64__) && defined(__APPLE__)
+#if defined(__aarch64__) && defined(__APPLE__) && !HAS_48_BIT_ADDRESS_SPACE
    ProtectRange(HeapMemEnd(), ShadowBeg());
    ProtectRange(ShadowEnd(), MetaShadowBeg());
    ProtectRange(MetaShadowEnd(), TraceMemBeg());
diff --git a/libsanitizer/tsan/tsan_report.cpp b/libsanitizer/tsan/tsan_report.cpp
index 968c7b97553..8ef9f0cd4fe 100644
--- a/libsanitizer/tsan/tsan_report.cpp
+++ b/libsanitizer/tsan/tsan_report.cpp
@@ -69,7 +69,7 @@ ReportDesc::~ReportDesc() {
  
  const int kThreadBufSize = 32;
  const char *thread_name(char *buf, int tid) {
-  if (tid == 0)
+  if (tid == kMainTid)
      return "main thread";
    internal_snprintf(buf, kThreadBufSize, "thread T%d", tid);
    return buf;
@@ -127,7 +127,7 @@ void PrintStack(const ReportStack *ent) {
    }
    SymbolizedStack *frame = ent->frames;
    for (int i = 0; frame && frame->info.address; frame = frame->next, i++) {
-    InternalScopedString res(2 * GetPageSizeCached());
+    InternalScopedString res;
      RenderFrame(&res, common_flags()->stack_trace_format, i,
                  frame->info.address, &frame->info,
                  common_flags()->symbolize_vs_style,
@@ -250,7 +250,7 @@ static void PrintMutex(const ReportMutex *rm) {
  
  static void PrintThread(const ReportThread *rt) {
    Decorator d;
-  if (rt->id == 0)  // Little sense in describing the main thread.
+  if (rt->id == kMainTid)  // Little sense in describing the main thread.
      return;
    Printf("%s", d.ThreadDescription());
    Printf("  Thread T%d", rt->id);
@@ -394,7 +394,7 @@ void PrintReport(const ReportDesc *rep) {
  
  #else  // #if !SANITIZER_GO
  
-const int kMainThreadId = 1;
+const u32 kMainGoroutineId = 1;
  
  void PrintStack(const ReportStack *ent) {
    if (ent == 0 || ent->frames == 0) {
@@ -415,7 +415,7 @@ static void PrintMop(const ReportMop *mop, bool first) {
    Printf("%s at %p by ",
        (first ? (mop->write ? "Write" : "Read")
               : (mop->write ? "Previous write" : "Previous read")), mop->addr);
-  if (mop->tid == kMainThreadId)
+  if (mop->tid == kMainGoroutineId)
      Printf("main goroutine:\n");
    else
      Printf("goroutine %d:\n", mop->tid);
@@ -428,7 +428,7 @@ static void PrintLocation(const ReportLocation *loc) {
      Printf("\n");
      Printf("Heap block of size %zu at %p allocated by ",
          loc->heap_chunk_size, loc->heap_chunk_start);
-    if (loc->tid == kMainThreadId)
+    if (loc->tid == kMainGoroutineId)
        Printf("main goroutine:\n");
      else
        Printf("goroutine %d:\n", loc->tid);
@@ -448,7 +448,7 @@ static void PrintLocation(const ReportLocation *loc) {
  }
  
  static void PrintThread(const ReportThread *rt) {
-  if (rt->id == kMainThreadId)
+  if (rt->id == kMainGoroutineId)
      return;
    Printf("\n");
    Printf("Goroutine %d (%s) created at:\n",
diff --git a/libsanitizer/tsan/tsan_rtl.cpp b/libsanitizer/tsan/tsan_rtl.cpp
index 3d721eb95a2..0efa99788ab 100644
--- a/libsanitizer/tsan/tsan_rtl.cpp
+++ b/libsanitizer/tsan/tsan_rtl.cpp
@@ -11,17 +11,19 @@
  // Main file (entry points) for the TSan run-time.
  //===----------------------------------------------------------------------===//
  
+#include "tsan_rtl.h"
+
  #include "sanitizer_common/sanitizer_atomic.h"
  #include "sanitizer_common/sanitizer_common.h"
  #include "sanitizer_common/sanitizer_file.h"
  #include "sanitizer_common/sanitizer_libc.h"
-#include "sanitizer_common/sanitizer_stackdepot.h"
  #include "sanitizer_common/sanitizer_placement_new.h"
+#include "sanitizer_common/sanitizer_stackdepot.h"
  #include "sanitizer_common/sanitizer_symbolizer.h"
  #include "tsan_defs.h"
-#include "tsan_platform.h"
-#include "tsan_rtl.h"
+#include "tsan_interface.h"
  #include "tsan_mman.h"
+#include "tsan_platform.h"
  #include "tsan_suppressions.h"
  #include "tsan_symbolize.h"
  #include "ubsan/ubsan_init.h"
@@ -56,12 +58,23 @@ Context *ctx;
  bool OnFinalize(bool failed);
  void OnInitialize();
  #else
+#include <dlfcn.h>
  SANITIZER_WEAK_CXX_DEFAULT_IMPL
  bool OnFinalize(bool failed) {
+#if !SANITIZER_GO
+  if (auto *ptr = dlsym(RTLD_DEFAULT, "__tsan_on_finalize"))
+    return reinterpret_cast<decltype(&__tsan_on_finalize)>(ptr)(failed);
+#endif
    return failed;
  }
  SANITIZER_WEAK_CXX_DEFAULT_IMPL
-void OnInitialize() {}
+void OnInitialize() {
+#if !SANITIZER_GO
+  if (auto *ptr = dlsym(RTLD_DEFAULT, "__tsan_on_initialize")) {
+    return reinterpret_cast<decltype(&__tsan_on_initialize)>(ptr)();
+  }
+#endif
+}
  #endif
  
  static char thread_registry_placeholder[sizeof(ThreadRegistry)];
@@ -77,12 +90,19 @@ static ThreadContextBase *CreateThreadContext(u32 tid) {
    new((void*)hdr) Trace();
    // We are going to use only a small part of the trace with the default
    // value of history_size. However, the constructor writes to the whole trace.
-  // Unmap the unused part.
+  // Release the unused part.
    uptr hdr_end = hdr + sizeof(Trace);
    hdr_end -= sizeof(TraceHeader) * (kTraceParts - TraceParts());
    hdr_end = RoundUp(hdr_end, GetPageSizeCached());
-  if (hdr_end < hdr + sizeof(Trace))
-    UnmapOrDie((void*)hdr_end, hdr + sizeof(Trace) - hdr_end);
+  if (hdr_end < hdr + sizeof(Trace)) {
+    ReleaseMemoryPagesToOS(hdr_end, hdr + sizeof(Trace));
+    uptr unused = hdr + sizeof(Trace) - hdr_end;
+    if (hdr_end != (uptr)MmapFixedNoAccess(hdr_end, unused)) {
+      Report("ThreadSanitizer: failed to mprotect(%p, %p)\n",
+          hdr_end, unused);
+      CHECK("unable to mprotect" && 0);
+    }
+  }
    void *mem = internal_alloc(MBlockThreadContex, sizeof(ThreadContext));
    return new(mem) ThreadContext(tid);
  }
@@ -94,42 +114,45 @@ static const u32 kThreadQuarantineSize = 64;
  #endif
  
  Context::Context()
-  : initialized()
-  , report_mtx(MutexTypeReport, StatMtxReport)
-  , nreported()
-  , nmissed_expected()
-  , thread_registry(new(thread_registry_placeholder) ThreadRegistry(
-      CreateThreadContext, kMaxTid, kThreadQuarantineSize, kMaxTidReuse))
-  , racy_mtx(MutexTypeRacy, StatMtxRacy)
-  , racy_stacks()
-  , racy_addresses()
-  , fired_suppressions_mtx(MutexTypeFired, StatMtxFired)
-  , clock_alloc("clock allocator") {
+    : initialized(),
+      report_mtx(MutexTypeReport, StatMtxReport),
+      nreported(),
+      nmissed_expected(),
+      thread_registry(new (thread_registry_placeholder) ThreadRegistry(
+          CreateThreadContext, kMaxTid, kThreadQuarantineSize, kMaxTidReuse)),
+      racy_mtx(MutexTypeRacy, StatMtxRacy),
+      racy_stacks(),
+      racy_addresses(),
+      fired_suppressions_mtx(MutexTypeFired, StatMtxFired),
+      clock_alloc(LINKER_INITIALIZED, "clock allocator") {
    fired_suppressions.reserve(8);
  }
  
  // The objects are allocated in TLS, so one may rely on zero-initialization.
-ThreadState::ThreadState(Context *ctx, int tid, int unique_id, u64 epoch,
-                         unsigned reuse_count,
-                         uptr stk_addr, uptr stk_size,
+ThreadState::ThreadState(Context *ctx, u32 tid, int unique_id, u64 epoch,
+                         unsigned reuse_count, uptr stk_addr, uptr stk_size,
                           uptr tls_addr, uptr tls_size)
-  : fast_state(tid, epoch)
-  // Do not touch these, rely on zero initialization,
-  // they may be accessed before the ctor.
-  // , ignore_reads_and_writes()
-  // , ignore_interceptors()
-  , clock(tid, reuse_count)
+    : fast_state(tid, epoch)
+      // Do not touch these, rely on zero initialization,
+      // they may be accessed before the ctor.
+      // , ignore_reads_and_writes()
+      // , ignore_interceptors()
+      ,
+      clock(tid, reuse_count)
  #if !SANITIZER_GO
-  , jmp_bufs()
+      ,
+      jmp_bufs()
  #endif
-  , tid(tid)
-  , unique_id(unique_id)
-  , stk_addr(stk_addr)
-  , stk_size(stk_size)
-  , tls_addr(tls_addr)
-  , tls_size(tls_size)
+      ,
+      tid(tid),
+      unique_id(unique_id),
+      stk_addr(stk_addr),
+      stk_size(stk_size),
+      tls_addr(tls_addr),
+      tls_size(tls_size)
  #if !SANITIZER_GO
-  , last_sleep_clock(tid)
+      ,
+      last_sleep_clock(tid)
  #endif
  {
  }
@@ -160,12 +183,12 @@ static void *BackgroundThread(void *arg) {
      } else if (internal_strcmp(flags()->profile_memory, "stderr") == 0) {
        mprof_fd = 2;
      } else {
-      InternalScopedString filename(kMaxPathLength);
+      InternalScopedString filename;
        filename.append("%s.%d", flags()->profile_memory, (int)internal_getpid());
        fd_t fd = OpenFile(filename.data(), WrOnly);
        if (fd == kInvalidFd) {
          Printf("ThreadSanitizer: failed to open memory profile file '%s'\n",
-            &filename[0]);
+               filename.data());
        } else {
          mprof_fd = fd;
        }
@@ -351,6 +374,18 @@ static void TsanOnDeadlySignal(int signo, void *siginfo, void *context) {
  }
  #endif
  
+void CheckUnwind() {
+  // There is high probability that interceptors will check-fail as well,
+  // on the other hand there is no sense in processing interceptors
+  // since we are going to die soon.
+  ScopedIgnoreInterceptors ignore;
+#if !SANITIZER_GO
+  cur_thread()->ignore_sync++;
+  cur_thread()->ignore_reads_and_writes++;
+#endif
+  PrintCurrentStackSlow(StackTrace::GetCurrentPc());
+}
+
  void Initialize(ThreadState *thr) {
    // Thread safe because done before all threads exist.
    static bool is_initialized = false;
@@ -361,7 +396,7 @@ void Initialize(ThreadState *thr) {
    ScopedIgnoreInterceptors ignore;
    SanitizerToolName = "ThreadSanitizer";
    // Install tool-specific callbacks in sanitizer_common.
-  SetCheckFailedCallback(TsanCheckFailed);
+  SetCheckUnwindCallback(CheckUnwind);
  
    ctx = new(ctx_placeholder) Context;
    const char *env_name = SANITIZER_GO ? "GORACE" : "TSAN_OPTIONS";
@@ -499,23 +534,27 @@ int Finalize(ThreadState *thr) {
  void ForkBefore(ThreadState *thr, uptr pc) {
    ctx->thread_registry->Lock();
    ctx->report_mtx.Lock();
-  // Ignore memory accesses in the pthread_atfork callbacks.
-  // If any of them triggers a data race we will deadlock
-  // on the report_mtx.
-  // We could ignore interceptors and sync operations as well,
+  // Suppress all reports in the pthread_atfork callbacks.
+  // Reports will deadlock on the report_mtx.
+  // We could ignore sync operations as well,
    // but so far it's unclear if it will do more good or harm.
    // Unnecessarily ignoring things can lead to false positives later.
-  ThreadIgnoreBegin(thr, pc);
+  thr->suppress_reports++;
+  // On OS X, REAL(fork) can call intercepted functions (OSSpinLockLock), and
+  // we'll assert in CheckNoLocks() unless we ignore interceptors.
+  thr->ignore_interceptors++;
  }
  
  void ForkParentAfter(ThreadState *thr, uptr pc) {
-  ThreadIgnoreEnd(thr, pc);  // Begin is in ForkBefore.
+  thr->suppress_reports--;  // Enabled in ForkBefore.
+  thr->ignore_interceptors--;
    ctx->report_mtx.Unlock();
    ctx->thread_registry->Unlock();
  }
  
  void ForkChildAfter(ThreadState *thr, uptr pc) {
-  ThreadIgnoreEnd(thr, pc);  // Begin is in ForkBefore.
+  thr->suppress_reports--;  // Enabled in ForkBefore.
+  thr->ignore_interceptors--;
    ctx->report_mtx.Unlock();
    ctx->thread_registry->Unlock();
  
diff --git a/libsanitizer/tsan/tsan_rtl.h b/libsanitizer/tsan/tsan_rtl.h
index 04d474e044e..3ae519d34da 100644
--- a/libsanitizer/tsan/tsan_rtl.h
+++ b/libsanitizer/tsan/tsan_rtl.h
@@ -84,9 +84,6 @@ typedef Allocator::AllocatorCache AllocatorCache;
  Allocator *allocator();
  #endif
  
-void TsanCheckFailed(const char *file, int line, const char *cond,
-                     u64 v1, u64 v2);
-
  const u64 kShadowRodata = (u64)-1;  // .rodata shadow marker
  
  // FastState (from most significant bit):
@@ -406,7 +403,7 @@ struct ThreadState {
  #if TSAN_COLLECT_STATS
    u64 stat[StatCnt];
  #endif
-  const int tid;
+  const u32 tid;
    const int unique_id;
    bool in_symbolizer;
    bool in_ignored_lib;
@@ -447,9 +444,8 @@ struct ThreadState {
  
    const ReportDesc *current_report;
  
-  explicit ThreadState(Context *ctx, int tid, int unique_id, u64 epoch,
-                       unsigned reuse_count,
-                       uptr stk_addr, uptr stk_size,
+  explicit ThreadState(Context *ctx, u32 tid, int unique_id, u64 epoch,
+                       unsigned reuse_count, uptr stk_addr, uptr stk_size,
                         uptr tls_addr, uptr tls_size);
  };
  
@@ -624,6 +620,7 @@ class ScopedReport : public ScopedReportBase {
    ScopedErrorReportLock lock_;
  };
  
+bool ShouldReport(ThreadState *thr, ReportType typ);
  ThreadContext *IsThreadStackOrTls(uptr addr, bool *is_stack);
  void RestoreStack(int tid, const u64 epoch, VarSizeStackTrace *stk,
                    MutexSet *mset, uptr *tag = nullptr);
diff --git a/libsanitizer/tsan/tsan_rtl_mutex.cpp b/libsanitizer/tsan/tsan_rtl_mutex.cpp
index 27897f0592b..0a8f3aa3ddb 100644
--- a/libsanitizer/tsan/tsan_rtl_mutex.cpp
+++ b/libsanitizer/tsan/tsan_rtl_mutex.cpp
@@ -51,6 +51,8 @@ static void ReportMutexMisuse(ThreadState *thr, uptr pc, ReportType typ,
    // or false positives (e.g. unlock in a different thread).
    if (SANITIZER_GO)
      return;
+  if (!ShouldReport(thr, typ))
+    return;
    ThreadRegistryLock l(ctx->thread_registry);
    ScopedReport rep(typ);
    rep.AddMutex(mid);
@@ -96,9 +98,8 @@ void MutexDestroy(ThreadState *thr, uptr pc, uptr addr, u32 flagz) {
      ctx->dd->MutexInit(&cb, &s->dd);
    }
    bool unlock_locked = false;
-  if (flags()->report_destroy_locked
-      && s->owner_tid != SyncVar::kInvalidTid
-      && !s->IsFlagSet(MutexFlagBroken)) {
+  if (flags()->report_destroy_locked && s->owner_tid != kInvalidTid &&
+      !s->IsFlagSet(MutexFlagBroken)) {
      s->SetFlags(MutexFlagBroken);
      unlock_locked = true;
    }
@@ -107,7 +108,7 @@ void MutexDestroy(ThreadState *thr, uptr pc, uptr addr, u32 flagz) {
    if (!unlock_locked)
      s->Reset(thr->proc());  // must not reset it before the report is printed
    s->mtx.Unlock();
-  if (unlock_locked) {
+  if (unlock_locked && ShouldReport(thr, ReportTypeMutexDestroyLocked)) {
      ThreadRegistryLock l(ctx->thread_registry);
      ScopedReport rep(ReportTypeMutexDestroyLocked);
      rep.AddMutex(mid);
@@ -169,7 +170,7 @@ void MutexPostLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz, int rec) {
    thr->fast_state.IncrementEpoch();
    TraceAddEvent(thr, thr->fast_state, EventTypeLock, s->GetId());
    bool report_double_lock = false;
-  if (s->owner_tid == SyncVar::kInvalidTid) {
+  if (s->owner_tid == kInvalidTid) {
      CHECK_EQ(s->recursion, 0);
      s->owner_tid = thr->tid;
      s->last_lock = thr->fast_state.raw();
@@ -229,7 +230,7 @@ int MutexUnlock(ThreadState *thr, uptr pc, uptr addr, u32 flagz) {
      s->recursion -= rec;
      if (s->recursion == 0) {
        StatInc(thr, StatMutexUnlock);
-      s->owner_tid = SyncVar::kInvalidTid;
+      s->owner_tid = kInvalidTid;
        ReleaseStoreImpl(thr, pc, &s->clock);
      } else {
        StatInc(thr, StatMutexRecUnlock);
@@ -275,7 +276,7 @@ void MutexPostReadLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz) {
    thr->fast_state.IncrementEpoch();
    TraceAddEvent(thr, thr->fast_state, EventTypeRLock, s->GetId());
    bool report_bad_lock = false;
-  if (s->owner_tid != SyncVar::kInvalidTid) {
+  if (s->owner_tid != kInvalidTid) {
      if (flags()->report_mutex_bugs && !s->IsFlagSet(MutexFlagBroken)) {
        s->SetFlags(MutexFlagBroken);
        report_bad_lock = true;
@@ -314,7 +315,7 @@ void MutexReadUnlock(ThreadState *thr, uptr pc, uptr addr) {
    thr->fast_state.IncrementEpoch();
    TraceAddEvent(thr, thr->fast_state, EventTypeRUnlock, s->GetId());
    bool report_bad_unlock = false;
-  if (s->owner_tid != SyncVar::kInvalidTid) {
+  if (s->owner_tid != kInvalidTid) {
      if (flags()->report_mutex_bugs && !s->IsFlagSet(MutexFlagBroken)) {
        s->SetFlags(MutexFlagBroken);
        report_bad_unlock = true;
@@ -344,7 +345,7 @@ void MutexReadOrWriteUnlock(ThreadState *thr, uptr pc, uptr addr) {
    SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
    bool write = true;
    bool report_bad_unlock = false;
-  if (s->owner_tid == SyncVar::kInvalidTid) {
+  if (s->owner_tid == kInvalidTid) {
      // Seems to be read unlock.
      write = false;
      StatInc(thr, StatMutexReadUnlock);
@@ -359,7 +360,7 @@ void MutexReadOrWriteUnlock(ThreadState *thr, uptr pc, uptr addr) {
      s->recursion--;
      if (s->recursion == 0) {
        StatInc(thr, StatMutexUnlock);
-      s->owner_tid = SyncVar::kInvalidTid;
+      s->owner_tid = kInvalidTid;
        ReleaseStoreImpl(thr, pc, &s->clock);
      } else {
        StatInc(thr, StatMutexRecUnlock);
@@ -387,7 +388,7 @@ void MutexReadOrWriteUnlock(ThreadState *thr, uptr pc, uptr addr) {
  void MutexRepair(ThreadState *thr, uptr pc, uptr addr) {
    DPrintf("#%d: MutexRepair %zx\n", thr->tid, addr);
    SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
-  s->owner_tid = SyncVar::kInvalidTid;
+  s->owner_tid = kInvalidTid;
    s->recursion = 0;
    s->mtx.Unlock();
  }
@@ -534,7 +535,7 @@ void AcquireReleaseImpl(ThreadState *thr, uptr pc, SyncClock *c) {
  }
  
  void ReportDeadlock(ThreadState *thr, uptr pc, DDReport *r) {
-  if (r == 0)
+  if (r == 0 || !ShouldReport(thr, ReportTypeDeadlock))
      return;
    ThreadRegistryLock l(ctx->thread_registry);
    ScopedReport rep(ReportTypeDeadlock);
diff --git a/libsanitizer/tsan/tsan_rtl_ppc64.S b/libsanitizer/tsan/tsan_rtl_ppc64.S
index 9e533a71a9c..8285e21aa1e 100644
--- a/libsanitizer/tsan/tsan_rtl_ppc64.S
+++ b/libsanitizer/tsan/tsan_rtl_ppc64.S
@@ -1,6 +1,5 @@
  #include "tsan_ppc_regs.h"
  
-        .machine altivec
          .section .text
          .hidden __tsan_setjmp
          .globl _setjmp
diff --git a/libsanitizer/tsan/tsan_rtl_report.cpp b/libsanitizer/tsan/tsan_rtl_report.cpp
index 208d0df44df..706794fdad1 100644
--- a/libsanitizer/tsan/tsan_rtl_report.cpp
+++ b/libsanitizer/tsan/tsan_rtl_report.cpp
@@ -31,23 +31,6 @@ using namespace __sanitizer;
  
  static ReportStack *SymbolizeStack(StackTrace trace);
  
-void TsanCheckFailed(const char *file, int line, const char *cond,
-                     u64 v1, u64 v2) {
-  // There is high probability that interceptors will check-fail as well,
-  // on the other hand there is no sense in processing interceptors
-  // since we are going to die soon.
-  ScopedIgnoreInterceptors ignore;
-#if !SANITIZER_GO
-  cur_thread()->ignore_sync++;
-  cur_thread()->ignore_reads_and_writes++;
-#endif
-  Printf("FATAL: ThreadSanitizer CHECK failed: "
-         "%s:%d \"%s\" (0x%zx, 0x%zx)\n",
-         file, line, cond, (uptr)v1, (uptr)v2);
-  PrintCurrentStackSlow(StackTrace::GetCurrentPc());
-  Die();
-}
-
  // Can be overriden by an application/test to intercept reports.
  #ifdef TSAN_EXTERNAL_HOOKS
  bool OnReport(const ReportDesc *rep, bool suppressed);
@@ -142,6 +125,34 @@ static ReportStack *SymbolizeStack(StackTrace trace) {
    return stack;
  }
  
+bool ShouldReport(ThreadState *thr, ReportType typ) {
+  // We set thr->suppress_reports in the fork context.
+  // Taking any locking in the fork context can lead to deadlocks.
+  // If any locks are already taken, it's too late to do this check.
+  CheckNoLocks(thr);
+  // For the same reason check we didn't lock thread_registry yet.
+  if (SANITIZER_DEBUG)
+    ThreadRegistryLock l(ctx->thread_registry);
+  if (!flags()->report_bugs || thr->suppress_reports)
+    return false;
+  switch (typ) {
+    case ReportTypeSignalUnsafe:
+      return flags()->report_signal_unsafe;
+    case ReportTypeThreadLeak:
+#if !SANITIZER_GO
+      // It's impossible to join phantom threads
+      // in the child after fork.
+      if (ctx->after_multithreaded_fork)
+        return false;
+#endif
+      return flags()->report_thread_leaks;
+    case ReportTypeMutexDestroyLocked:
+      return flags()->report_destroy_locked;
+    default:
+      return true;
+  }
+}
+
  ScopedReportBase::ScopedReportBase(ReportType typ, uptr tag) {
    ctx->thread_registry->CheckLocked();
    void *mem = internal_alloc(MBlockReport, sizeof(ReportDesc));
@@ -497,8 +508,10 @@ static bool HandleRacyAddress(ThreadState *thr, uptr addr_min, uptr addr_max) {
  }
  
  bool OutputReport(ThreadState *thr, const ScopedReport &srep) {
-  if (!flags()->report_bugs || thr->suppress_reports)
-    return false;
+  // These should have been checked in ShouldReport.
+  // It's too late to check them here, we have already taken locks.
+  CHECK(flags()->report_bugs);
+  CHECK(!thr->suppress_reports);
    atomic_store_relaxed(&ctx->last_symbolize_time_ns, NanoTime());
    const ReportDesc *rep = srep.GetReport();
    CHECK_EQ(thr->current_report, nullptr);
@@ -589,7 +602,7 @@ void ReportRace(ThreadState *thr) {
    // at best it will cause deadlocks on internal mutexes.
    ScopedIgnoreInterceptors ignore;
  
-  if (!flags()->report_bugs)
+  if (!ShouldReport(thr, ReportTypeRace))
      return;
    if (!flags()->report_atomic_races && !RaceBetweenAtomicAndFree(thr))
      return;
@@ -722,8 +735,7 @@ void PrintCurrentStack(ThreadState *thr, uptr pc) {
  // However, this solution is not reliable enough, please see dvyukov's comment
  // http://reviews.llvm.org/D19148#406208
  // Also see PR27280 comment 2 and 3 for breaking examples and analysis.
-ALWAYS_INLINE
-void PrintCurrentStackSlow(uptr pc) {
+ALWAYS_INLINE USED void PrintCurrentStackSlow(uptr pc) {
  #if !SANITIZER_GO
    uptr bp = GET_CURRENT_FRAME();
    BufferedStackTrace *ptrace =
diff --git a/libsanitizer/tsan/tsan_rtl_thread.cpp b/libsanitizer/tsan/tsan_rtl_thread.cpp
index d80146735ea..6d1ccd8c9c7 100644
--- a/libsanitizer/tsan/tsan_rtl_thread.cpp
+++ b/libsanitizer/tsan/tsan_rtl_thread.cpp
@@ -51,7 +51,7 @@ struct OnCreatedArgs {
  
  void ThreadContext::OnCreated(void *arg) {
    thr = 0;
-  if (tid == 0)
+  if (tid == kMainTid)
      return;
    OnCreatedArgs *args = static_cast<OnCreatedArgs *>(arg);
    if (!args->thr)  // GCD workers don't have a parent thread.
@@ -179,7 +179,7 @@ static void MaybeReportThreadLeak(ThreadContextBase *tctx_base, void *arg) {
  
  #if !SANITIZER_GO
  static void ReportIgnoresEnabled(ThreadContext *tctx, IgnoreSet *set) {
-  if (tctx->tid == 0) {
+  if (tctx->tid == kMainTid) {
      Printf("ThreadSanitizer: main thread finished with ignores enabled\n");
    } else {
      Printf("ThreadSanitizer: thread T%d %s finished with ignores enabled,"
@@ -210,7 +210,7 @@ static void ThreadCheckIgnore(ThreadState *thr) {}
  void ThreadFinalize(ThreadState *thr) {
    ThreadCheckIgnore(thr);
  #if !SANITIZER_GO
-  if (!flags()->report_thread_leaks)
+  if (!ShouldReport(thr, ReportTypeThreadLeak))
      return;
    ThreadRegistryLock l(ctx->thread_registry);
    Vector<ThreadLeak> leaks;
@@ -250,9 +250,10 @@ void ThreadStart(ThreadState *thr, int tid, tid_t os_id,
    uptr tls_size = 0;
  #if !SANITIZER_GO
    if (thread_type != ThreadType::Fiber)
-    GetThreadStackAndTls(tid == 0, &stk_addr, &stk_size, &tls_addr, &tls_size);
+    GetThreadStackAndTls(tid == kMainTid, &stk_addr, &stk_size, &tls_addr,
+                         &tls_size);
  
-  if (tid) {
+  if (tid != kMainTid) {
      if (stk_addr && stk_size)
        MemoryRangeImitateWrite(thr, /*pc=*/ 1, stk_addr, stk_size);
  
@@ -313,7 +314,7 @@ static bool ConsumeThreadByUid(ThreadContextBase *tctx, void *arg) {
  int ThreadConsumeTid(ThreadState *thr, uptr pc, uptr uid) {
    ConsumeThreadContext findCtx = {uid, nullptr};
    ctx->thread_registry->FindThread(ConsumeThreadByUid, &findCtx);
-  int tid = findCtx.tctx ? findCtx.tctx->tid : ThreadRegistry::kUnknownTid;
+  int tid = findCtx.tctx ? findCtx.tctx->tid : kInvalidTid;
    DPrintf("#%d: ThreadTid uid=%zu tid=%d\n", thr->tid, uid, tid);
    return tid;
  }
diff --git a/libsanitizer/tsan/tsan_sync.cpp b/libsanitizer/tsan/tsan_sync.cpp
index 17ddd50f128..ba24f98ae9f 100644
--- a/libsanitizer/tsan/tsan_sync.cpp
+++ b/libsanitizer/tsan/tsan_sync.cpp
@@ -53,8 +53,8 @@ void SyncVar::Reset(Processor *proc) {
  }
  
  MetaMap::MetaMap()
-    : block_alloc_("heap block allocator")
-    , sync_alloc_("sync allocator") {
+    : block_alloc_(LINKER_INITIALIZED, "heap block allocator"),
+      sync_alloc_(LINKER_INITIALIZED, "sync allocator") {
    atomic_store(&uid_gen_, 0, memory_order_relaxed);
  }
  
diff --git a/libsanitizer/tsan/tsan_sync.h b/libsanitizer/tsan/tsan_sync.h
index 47f2739d8de..c4056f684d7 100644
--- a/libsanitizer/tsan/tsan_sync.h
+++ b/libsanitizer/tsan/tsan_sync.h
@@ -50,13 +50,11 @@ enum MutexFlags {
  struct SyncVar {
    SyncVar();
  
-  static const int kInvalidTid = -1;
-
    uptr addr;  // overwritten by DenseSlabAlloc freelist
    Mutex mtx;
    u64 uid;  // Globally unique id.
    u32 creation_stack_id;
-  int owner_tid;  // Set only by exclusive owners.
+  u32 owner_tid;  // Set only by exclusive owners.
    u64 last_lock;
    int recursion;
    atomic_uint32_t flags;
@@ -130,8 +128,8 @@ class MetaMap {
    static const u32 kFlagMask  = 3u << 30;
    static const u32 kFlagBlock = 1u << 30;
    static const u32 kFlagSync  = 2u << 30;
-  typedef DenseSlabAlloc<MBlock, 1<<16, 1<<12> BlockAlloc;
-  typedef DenseSlabAlloc<SyncVar, 1<<16, 1<<10> SyncAlloc;
+  typedef DenseSlabAlloc<MBlock, 1 << 18, 1 << 12, kFlagMask> BlockAlloc;
+  typedef DenseSlabAlloc<SyncVar, 1 << 20, 1 << 10, kFlagMask> SyncAlloc;
    BlockAlloc block_alloc_;
    SyncAlloc sync_alloc_;
    atomic_uint64_t uid_gen_;
diff --git a/libsanitizer/ubsan/ubsan_diag.cpp b/libsanitizer/ubsan/ubsan_diag.cpp
index 1b2828d236d..ef2e495cac8 100644
--- a/libsanitizer/ubsan/ubsan_diag.cpp
+++ b/libsanitizer/ubsan/ubsan_diag.cpp
@@ -278,7 +278,7 @@ static void PrintMemorySnippet(const Decorator &Decor, MemoryLocation Loc,
    }
  
    // Emit data.
-  InternalScopedString Buffer(1024);
+  InternalScopedString Buffer;
    for (uptr P = Min; P != Max; ++P) {
      unsigned char C = *reinterpret_cast<const unsigned char*>(P);
      Buffer.append("%s%02x", (P % 8 == 0) ? "  " : " ", C);
@@ -346,7 +346,7 @@ Diag::~Diag() {
    // All diagnostics should be printed under report mutex.
    ScopedReport::CheckLocked();
    Decorator Decor;
-  InternalScopedString Buffer(1024);
+  InternalScopedString Buffer;
  
    // Prepare a report that a monitor process can inspect.
    if (Level == DL_Error) {
@@ -388,6 +388,10 @@ ScopedReport::ScopedReport(ReportOptions Opts, Location SummaryLoc,
  ScopedReport::~ScopedReport() {
    MaybePrintStackTrace(Opts.pc, Opts.bp);
    MaybeReportErrorSummary(SummaryLoc, Type);
+
+  if (common_flags()->print_module_map >= 2)
+    DumpProcessMap();
+
    if (flags()->halt_on_error)
      Die();
  }
diff --git a/libsanitizer/ubsan/ubsan_flags.cpp b/libsanitizer/ubsan/ubsan_flags.cpp
index 9a66bd37518..25cefd46ce2 100644
--- a/libsanitizer/ubsan/ubsan_flags.cpp
+++ b/libsanitizer/ubsan/ubsan_flags.cpp
@@ -50,7 +50,6 @@ void InitializeFlags() {
    {
      CommonFlags cf;
      cf.CopyFrom(*common_flags());
-    cf.print_summary = false;
      cf.external_symbolizer_path = GetFlag("UBSAN_SYMBOLIZER_PATH");
      OverrideCommonFlags(cf);
    }
diff --git a/libsanitizer/ubsan/ubsan_handlers.cpp b/libsanitizer/ubsan/ubsan_handlers.cpp
index 2184625aa6e..e201e6bba22 100644
--- a/libsanitizer/ubsan/ubsan_handlers.cpp
+++ b/libsanitizer/ubsan/ubsan_handlers.cpp
@@ -894,21 +894,6 @@ void __ubsan_handle_cfi_bad_type(CFICheckFailData *Data, ValueHandle Vtable,
  
  }  // namespace __ubsan
  
-void __ubsan::__ubsan_handle_cfi_bad_icall(CFIBadIcallData *CallData,
-                                           ValueHandle Function) {
-  GET_REPORT_OPTIONS(false);
-  CFICheckFailData Data = {CFITCK_ICall, CallData->Loc, CallData->Type};
-  handleCFIBadIcall(&Data, Function, Opts);
-}
-
-void __ubsan::__ubsan_handle_cfi_bad_icall_abort(CFIBadIcallData *CallData,
-                                                 ValueHandle Function) {
-  GET_REPORT_OPTIONS(true);
-  CFICheckFailData Data = {CFITCK_ICall, CallData->Loc, CallData->Type};
-  handleCFIBadIcall(&Data, Function, Opts);
-  Die();
-}
-
  void __ubsan::__ubsan_handle_cfi_check_fail(CFICheckFailData *Data,
                                              ValueHandle Value,
                                              uptr ValidVtable) {
diff --git a/libsanitizer/ubsan/ubsan_handlers.h b/libsanitizer/ubsan/ubsan_handlers.h
index 9f412353fc0..219fb15de55 100644
--- a/libsanitizer/ubsan/ubsan_handlers.h
+++ b/libsanitizer/ubsan/ubsan_handlers.h
@@ -215,20 +215,12 @@ enum CFITypeCheckKind : unsigned char {
    CFITCK_VMFCall,
  };
  
-struct CFIBadIcallData {
-  SourceLocation Loc;
-  const TypeDescriptor &Type;
-};
-
  struct CFICheckFailData {
    CFITypeCheckKind CheckKind;
    SourceLocation Loc;
    const TypeDescriptor &Type;
  };
  
-/// \brief Handle control flow integrity failure for indirect function calls.
-RECOVERABLE(cfi_bad_icall, CFIBadIcallData *Data, ValueHandle Function)
-
  /// \brief Handle control flow integrity failures.
  RECOVERABLE(cfi_check_fail, CFICheckFailData *Data, ValueHandle Function,
              uptr VtableIsValid)
diff --git a/libsanitizer/ubsan/ubsan_init.cpp b/libsanitizer/ubsan/ubsan_init.cpp
index e0be5a72ec4..9931d85bf40 100644
--- a/libsanitizer/ubsan/ubsan_init.cpp
+++ b/libsanitizer/ubsan/ubsan_init.cpp
@@ -33,6 +33,11 @@ static void CommonInit() {
    InitializeSuppressions();
  }
  
+static void UbsanDie() {
+  if (common_flags()->print_module_map >= 1)
+    DumpProcessMap();
+}
+
  static void CommonStandaloneInit() {
    SanitizerToolName = GetSanititizerToolName();
    CacheBinaryName();
@@ -42,6 +47,10 @@ static void CommonStandaloneInit() {
    AndroidLogInit();
    InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
    CommonInit();
+
+  // Only add die callback when running in standalone mode to avoid printing
+  // the same information from multiple sanitizers' output
+  AddDieCallback(UbsanDie);
    Symbolizer::LateInitialize();
  }
  
diff --git a/libsanitizer/ubsan/ubsan_monitor.cpp b/libsanitizer/ubsan/ubsan_monitor.cpp
index d064e95f76f..69dd986f9bd 100644
--- a/libsanitizer/ubsan/ubsan_monitor.cpp
+++ b/libsanitizer/ubsan/ubsan_monitor.cpp
@@ -17,7 +17,7 @@ using namespace __ubsan;
  UndefinedBehaviorReport::UndefinedBehaviorReport(const char *IssueKind,
                                                   Location &Loc,
                                                   InternalScopedString &Msg)
-    : IssueKind(IssueKind), Loc(Loc), Buffer(Msg.length() + 1) {
+    : IssueKind(IssueKind), Loc(Loc) {
    // We have the common sanitizer reporting lock, so it's safe to register a
    // new UB report.
    RegisterUndefinedBehaviorReport(this);
@@ -52,9 +52,9 @@ void __ubsan::__ubsan_get_current_report_data(const char **OutIssueKind,
  
    // Ensure that the first character of the diagnostic text can't start with a
    // lowercase letter.
-  char FirstChar = Buf.data()[0];
+  char FirstChar = *Buf.data();
    if (FirstChar >= 'a' && FirstChar <= 'z')
-    Buf.data()[0] = FirstChar - 'a' + 'A';
+    *Buf.data() += 'A' - 'a';
  
    *OutIssueKind = CurrentUBR->IssueKind;
    *OutMessage = Buf.data();
diff --git a/libsanitizer/ubsan/ubsan_platform.h b/libsanitizer/ubsan/ubsan_platform.h
index 98542fcea96..51e535d1e22 100644
--- a/libsanitizer/ubsan/ubsan_platform.h
+++ b/libsanitizer/ubsan/ubsan_platform.h
@@ -12,16 +12,14 @@
  #ifndef UBSAN_PLATFORM_H
  #define UBSAN_PLATFORM_H
  
-#ifndef CAN_SANITIZE_UB
  // Other platforms should be easy to add, and probably work as-is.
  #if defined(__linux__) || defined(__FreeBSD__) || defined(__APPLE__) ||        \
-    defined(__NetBSD__) || \
+    defined(__NetBSD__) || defined(__DragonFly__) || \
      (defined(__sun__) && defined(__svr4__)) || \
      defined(_WIN32) || defined(__Fuchsia__) || defined(__rtems__)
  # define CAN_SANITIZE_UB 1
  #else
  # define CAN_SANITIZE_UB 0
  #endif
-#endif //CAN_SANITIZE_UB
  
  #endif
-- 
2.31.1


             reply	other threads:[~2021-05-13  7:28 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-13  7:28 Martin Liška [this message]
2021-05-13 15:54 ` H.J. Lu
2021-05-13 17:27   ` Martin Liška
2021-05-13 20:01     ` H.J. Lu
2021-05-13 20:11       ` H.J. Lu
2021-05-14  1:26         ` [PATCH] libsanitizer: cherry-pick from upstream H.J. Lu
2021-06-04  7:32 ` [PATCH] libsanitizer: merge from master Hongtao Liu
2021-06-04  7:36   ` Martin Liška
2021-06-04  7:53     ` Hongtao Liu
  -- strict thread matches above, loose matches on Subject: below --
2020-06-02  6:00 [PATCH] Libsanitizer: " Martin Liška
2020-06-06 19:47 ` Andreas Schwab
2020-10-16  8:59 ` Martin Liška
2020-10-19  7:04   ` Tobias Burnus
2020-10-19  7:11     ` Martin Liška
2020-10-19  7:39       ` Tobias Burnus
2020-10-20  8:09         ` Tobias Burnus
2020-10-20  9:16           ` Martin Liška

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