From: "H.J. Lu" <hjl.tools@gmail.com>
To: binutils@sourceware.org
Subject: [PATCH] Don't complain undefined weak dynamic reference
Date: Thu, 25 Apr 2019 21:20:00 -0000 [thread overview]
Message-ID: <20190425212000.4919-1-hjl.tools@gmail.com> (raw)
When undefined non-weak references in IR objects are optimized out
by LTO, we can have weak dynamic referencs to symbols marked with
bfd_link_hash_undefined. We shouldn't complain such undefined weak
dynamic references.
bfd/
PR ld/24486
* elflink.c (elf_link_output_extsym): Don't complain undefined
weak dynamic reference.
ld/
PR ld/24486
* testsuite/ld-plugin/lto.exp: Run PR ld/24486 tests.
* testsuite/ld-plugin/pr24486a.c: New file.
* testsuite/ld-plugin/pr24486b.c: Likewise.
* testsuite/ld-plugin/pr24486c.c: Likewise.
---
bfd/elflink.c | 2 +-
ld/testsuite/ld-plugin/lto.exp | 12 ++++++++++++
ld/testsuite/ld-plugin/pr24486a.c | 8 ++++++++
ld/testsuite/ld-plugin/pr24486b.c | 8 ++++++++
ld/testsuite/ld-plugin/pr24486c.c | 1 +
5 files changed, 30 insertions(+), 1 deletion(-)
create mode 100644 ld/testsuite/ld-plugin/pr24486a.c
create mode 100644 ld/testsuite/ld-plugin/pr24486b.c
create mode 100644 ld/testsuite/ld-plugin/pr24486c.c
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 81e667dab0..ddeaa08d50 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -9776,7 +9776,7 @@ elf_link_output_extsym (struct bfd_hash_entry *bh, void *data)
/* If we are reporting errors for this situation then do so now. */
if (!ignore_undef
- && h->ref_dynamic
+ && h->ref_dynamic_nonweak
&& (!h->ref_regular || flinfo->info->gc_sections)
&& !elf_link_check_versioned_symbol (flinfo->info, bed, h)
&& flinfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
diff --git a/ld/testsuite/ld-plugin/lto.exp b/ld/testsuite/ld-plugin/lto.exp
index b13a77333f..e913c6f203 100644
--- a/ld/testsuite/ld-plugin/lto.exp
+++ b/ld/testsuite/ld-plugin/lto.exp
@@ -325,6 +325,18 @@ set lto_link_elf_tests [list \
[list {Build pr22220main.o} \
{} {-flto} \
{pr22220main.cc} {} {} {c++}] \
+ [list "Build pr24486a.o" \
+ "$plug_opt" "-flto -O2" \
+ {pr24486a.c} {} "" "c"] \
+ [list "Build pr24486b.so" \
+ "-shared" "-O2 -fpic" \
+ {pr24486b.c} {} "pr24486b.so" "c"] \
+ [list "Build pr24486c.so" \
+ "-shared -Wl,--no-as-needed tmpdir/pr24486b.so" "-O2 -fpic" \
+ {pr24486c.c} {} "pr24486c.so" "c"] \
+ [list "PR ld/24486" \
+ "-O2 -flto tmpdir/pr24486a.o tmpdir/pr24486c.so -Wl,--as-needed tmpdir/pr24486b.so" "" \
+ {dummy.c} {} "pr24486.exe"] \
]
# PR 14918 checks that libgcc is not spuriously included in a shared link of
diff --git a/ld/testsuite/ld-plugin/pr24486a.c b/ld/testsuite/ld-plugin/pr24486a.c
new file mode 100644
index 0000000000..def0139598
--- /dev/null
+++ b/ld/testsuite/ld-plugin/pr24486a.c
@@ -0,0 +1,8 @@
+extern int FLAGS_verbose;
+extern void bar (void);
+int
+a(void) {
+return FLAGS_verbose;
+}
+void unused (void) { bar(); }
+int main() { return a (); }
diff --git a/ld/testsuite/ld-plugin/pr24486b.c b/ld/testsuite/ld-plugin/pr24486b.c
new file mode 100644
index 0000000000..3aabe2a395
--- /dev/null
+++ b/ld/testsuite/ld-plugin/pr24486b.c
@@ -0,0 +1,8 @@
+extern void bar (void) __attribute__((weak));
+
+void
+foo (void)
+{
+ if (bar)
+ bar ();
+}
diff --git a/ld/testsuite/ld-plugin/pr24486c.c b/ld/testsuite/ld-plugin/pr24486c.c
new file mode 100644
index 0000000000..f289177d3e
--- /dev/null
+++ b/ld/testsuite/ld-plugin/pr24486c.c
@@ -0,0 +1 @@
+int FLAGS_verbose;
--
2.20.1
next reply other threads:[~2019-04-25 21:20 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-25 21:20 H.J. Lu [this message]
2019-04-25 23:38 ` Alan Modra
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