[PATCH 0/5] Random cleanup patches

[PATCH 0/5] Random cleanup patches

[Simon Marchi]

Here are some more preparatory patches that are in the series I'm
currently working on.  I think they make sense on their own, so here
they are.

Simon Marchi (5):
  gdb: add program_space parameter to mark_breakpoints_out
  gdb: add inferior parameter to breakpoint_init_inferior
  gdb: add program_space parameter to disable_breakpoints_in_shlibs
  gdb: add program_space parameter to clear_solib
  gdb: remove unnecessary nullptr check in remove_user_added_objfile

 gdb/breakpoint.c  | 35 +++++++++++------------------------
 gdb/breakpoint.h  | 22 ++++++++++++++++++----
 gdb/corelow.c     |  2 +-
 gdb/infcmd.c      | 10 +++++-----
 gdb/infrun.c      |  6 +++---
 gdb/solib.c       | 23 +++++++++++++----------
 gdb/solib.h       |  6 +++---
 gdb/symtab.h      |  4 ----
 gdb/target.c      |  4 ++--
 gdb/windows-nat.c |  2 +-
 10 files changed, 57 insertions(+), 57 deletions(-)


base-commit: 6fdf95ae532c61263e19e2036cfe3057bb928385
-- 
2.43.0

[PATCH 1/5] gdb: add program_space parameter to mark_breakpoints_out

[Simon Marchi]

Make the current_program_space reference bubble up one level.

Change-Id: Idc8ed78d23bf3bb2969f6963d8cc049f26901c29
---
 gdb/breakpoint.c | 8 ++++----
 gdb/breakpoint.h | 5 +++--
 gdb/infrun.c     | 2 +-
 gdb/target.c     | 2 +-
 4 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 7d1171ec35eb..d844ef7baf25 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -4216,13 +4216,13 @@ remove_breakpoint (struct bp_location *bl)
   return remove_breakpoint_1 (bl, REMOVE_BREAKPOINT);
 }
 
-/* Clear the "inserted" flag in all breakpoints.  */
+/* See breakpoint.h.  */
 
 void
-mark_breakpoints_out (void)
+mark_breakpoints_out (program_space *pspace)
 {
   for (bp_location *bl : all_bp_locations ())
-    if (bl->pspace == current_program_space)
+    if (bl->pspace == pspace)
       bl->inserted = 0;
 }
 
@@ -4248,7 +4248,7 @@ breakpoint_init_inferior (enum inf_context context)
   if (gdbarch_has_global_breakpoints (current_inferior ()->arch ()))
     return;
 
-  mark_breakpoints_out ();
+  mark_breakpoints_out (pspace);
 
   for (breakpoint &b : all_breakpoints_safe ())
     {
diff --git a/gdb/breakpoint.h b/gdb/breakpoint.h
index 93c49520e8ce..e7bebed2725d 100644
--- a/gdb/breakpoint.h
+++ b/gdb/breakpoint.h
@@ -1764,8 +1764,9 @@ extern void breakpoint_set_inferior (struct breakpoint *b, int inferior);
 
 extern void breakpoint_set_task (struct breakpoint *b, int task);
 
-/* Clear the "inserted" flag in all breakpoints.  */
-extern void mark_breakpoints_out (void);
+/* Clear the "inserted" flag in all breakpoints locations in PSPACE.  */
+
+extern void mark_breakpoints_out (program_space *pspace);
 
 extern struct breakpoint *create_jit_event_breakpoint (struct gdbarch *,
 						       CORE_ADDR);
diff --git a/gdb/infrun.c b/gdb/infrun.c
index 87965fb12742..d00a98906d71 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -1247,7 +1247,7 @@ follow_exec (ptid_t ptid, const char *exec_file_target)
      value that was overwritten with a TRAP instruction).  Since
      we now have a new a.out, those shadow contents aren't valid.  */
 
-  mark_breakpoints_out ();
+  mark_breakpoints_out (current_program_space);
 
   /* The target reports the exec event to the main thread, even if
      some other thread does the exec, and even if the main thread was
diff --git a/gdb/target.c b/gdb/target.c
index ec75f952ea20..e72e22da69a3 100644
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -3628,7 +3628,7 @@ generic_mourn_inferior (void)
   /* Mark breakpoints uninserted in case something tries to delete a
      breakpoint while we delete the inferior's threads (which would
      fail, since the inferior is long gone).  */
-  mark_breakpoints_out ();
+  mark_breakpoints_out (inf->pspace);
 
   if (inf->pid != 0)
     exit_inferior (inf);
-- 
2.43.0

[PATCH 2/5] gdb: add inferior parameter to breakpoint_init_inferior

[Simon Marchi]

By inspection, I believe that breakpoint_init_inferior doesn't call
anything that relies on the current program space or inferior.  So,
add an inferior parameter, to make the current inferior / program space
references bubble up one level.

Change-Id: Ib07b7a6d360e324f6ae1aa502dd314b8cce421b7
---
 gdb/breakpoint.c | 22 +++++-----------------
 gdb/breakpoint.h | 12 +++++++++++-
 gdb/infcmd.c     | 10 +++++-----
 gdb/infrun.c     |  4 ++--
 gdb/target.c     |  2 +-
 5 files changed, 24 insertions(+), 26 deletions(-)

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index d844ef7baf25..8d8e97400e37 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -4226,33 +4226,21 @@ mark_breakpoints_out (program_space *pspace)
       bl->inserted = 0;
 }
 
-/* Clear the "inserted" flag in all breakpoints and delete any
-   breakpoints which should go away between runs of the program.
-
-   Plus other such housekeeping that has to be done for breakpoints
-   between runs.
-
-   Note: this function gets called at the end of a run (by
-   generic_mourn_inferior) and when a run begins (by
-   init_wait_for_inferior).  */
-
-
+/* See breakpoint.h.  */
 
 void
-breakpoint_init_inferior (enum inf_context context)
+breakpoint_init_inferior (inferior *inf, inf_context context)
 {
-  struct program_space *pspace = current_program_space;
-
   /* If breakpoint locations are shared across processes, then there's
      nothing to do.  */
-  if (gdbarch_has_global_breakpoints (current_inferior ()->arch ()))
+  if (gdbarch_has_global_breakpoints (inf->arch ()))
     return;
 
-  mark_breakpoints_out (pspace);
+  mark_breakpoints_out (inf->pspace);
 
   for (breakpoint &b : all_breakpoints_safe ())
     {
-      if (b.has_locations () && b.first_loc ().pspace != pspace)
+      if (b.has_locations () && b.first_loc ().pspace != inf->pspace)
 	continue;
 
       switch (b.type)
diff --git a/gdb/breakpoint.h b/gdb/breakpoint.h
index e7bebed2725d..8530a7127945 100644
--- a/gdb/breakpoint.h
+++ b/gdb/breakpoint.h
@@ -1515,7 +1515,17 @@ extern struct breakpoint *clone_momentary_breakpoint (struct breakpoint *bpkt);
 
 extern void set_ignore_count (int, int, int);
 
-extern void breakpoint_init_inferior (enum inf_context);
+/* Clear the "inserted" flag in all breakpoint locations of INF's program space
+   and delete any breakpoints which should go away between runs of the program.
+
+   Plus other such housekeeping that has to be done for breakpoints
+   between runs.
+
+   Note: this function gets called at the end of a run (by
+   generic_mourn_inferior) and when a run begins (by
+   init_wait_for_inferior).  */
+
+extern void breakpoint_init_inferior (inferior *inf, inf_context context);
 
 extern void breakpoint_auto_delete (bpstat *);
 
diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index 54063b37beb8..4e17a6b06295 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -2824,14 +2824,14 @@ detach_command (const char *args, int from_tty)
   /* Hold a strong reference to the target while (maybe)
      detaching the parent.  Otherwise detaching could close the
      target.  */
-  auto target_ref
-    = target_ops_ref::new_reference (current_inferior ()->process_target ());
+  inferior *inf = current_inferior ();
+  auto target_ref = target_ops_ref::new_reference (inf->process_target ());
 
   /* Save this before detaching, since detaching may unpush the
      process_stratum target.  */
   bool was_non_stop_p = target_is_non_stop_p ();
 
-  target_detach (current_inferior (), from_tty);
+  target_detach (inf, from_tty);
 
   update_previous_thread ();
 
@@ -2840,11 +2840,11 @@ detach_command (const char *args, int from_tty)
      this within target_detach because that is also used when
      following child forks, and in that case we will want to transfer
      breakpoints to the child, not delete them.  */
-  breakpoint_init_inferior (inf_exited);
+  breakpoint_init_inferior (inf, inf_exited);
 
   /* If the solist is global across inferiors, don't clear it when we
      detach from a single inferior.  */
-  if (!gdbarch_has_global_solist (current_inferior ()->arch ()))
+  if (!gdbarch_has_global_solist (inf->arch ()))
     no_shared_libraries (nullptr, from_tty);
 
   if (deprecated_detach_hook)
diff --git a/gdb/infrun.c b/gdb/infrun.c
index d00a98906d71..fa68ab8296e9 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -1297,7 +1297,7 @@ follow_exec (ptid_t ptid, const char *exec_file_target)
   /* We've followed the inferior through an exec.  Therefore, the
      inferior has essentially been killed & reborn.  */
 
-  breakpoint_init_inferior (inf_execd);
+  breakpoint_init_inferior (current_inferior (), inf_execd);
 
   gdb::unique_xmalloc_ptr<char> exec_file_host
     = exec_file_find (exec_file_target, nullptr);
@@ -3819,7 +3819,7 @@ init_wait_for_inferior (void)
 {
   /* These are meaningless until the first time through wait_for_inferior.  */
 
-  breakpoint_init_inferior (inf_starting);
+  breakpoint_init_inferior (current_inferior (), inf_starting);
 
   clear_proceed_status (0);
 
diff --git a/gdb/target.c b/gdb/target.c
index e72e22da69a3..bbc1badc9e19 100644
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -3636,7 +3636,7 @@ generic_mourn_inferior (void)
   /* Note this wipes step-resume breakpoints, so needs to be done
      after exit_inferior, which ends up referencing the step-resume
      breakpoints through clear_thread_inferior_resources.  */
-  breakpoint_init_inferior (inf_exited);
+  breakpoint_init_inferior (inf, inf_exited);
 
   registers_changed ();
 
-- 
2.43.0

[PATCH 3/5] gdb: add program_space parameter to disable_breakpoints_in_shlibs

[Simon Marchi]

Make the current_program_space reference bubble up one level.

Change-Id: Ide917aa306bff1872d961244901d79f65d2da62e
---
 gdb/breakpoint.c  | 7 +++----
 gdb/breakpoint.h  | 5 ++++-
 gdb/solib.c       | 2 +-
 gdb/windows-nat.c | 2 +-
 4 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 8d8e97400e37..5f05657a8b3e 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -7972,11 +7972,10 @@ create_and_insert_solib_event_breakpoint (struct gdbarch *gdbarch, CORE_ADDR add
   return b;
 }
 
-/* Disable any breakpoints that are on code in shared libraries.  Only
-   apply to enabled breakpoints, disabled ones can just stay disabled.  */
+/* See breakpoint.h.  */
 
 void
-disable_breakpoints_in_shlibs (void)
+disable_breakpoints_in_shlibs (program_space *pspace)
 {
   for (bp_location *loc : all_bp_locations ())
     {
@@ -7992,7 +7991,7 @@ disable_breakpoints_in_shlibs (void)
 	   || (b->type == bp_jit_event)
 	   || (b->type == bp_hardware_breakpoint)
 	   || (is_tracepoint (b)))
-	  && loc->pspace == current_program_space
+	  && loc->pspace == pspace
 	  && !loc->shlib_disabled
 	  && solib_name_from_address (loc->pspace, loc->address)
 	  )
diff --git a/gdb/breakpoint.h b/gdb/breakpoint.h
index 8530a7127945..226e4d06993e 100644
--- a/gdb/breakpoint.h
+++ b/gdb/breakpoint.h
@@ -1802,7 +1802,10 @@ extern void remove_solib_event_breakpoints (void);
    delete at next stop disposition.  */
 extern void remove_solib_event_breakpoints_at_next_stop (void);
 
-extern void disable_breakpoints_in_shlibs (void);
+/* Disable any breakpoints that are on code in shared libraries in PSPACE.
+   Only apply to enabled breakpoints, disabled ones can just stay disabled.  */
+
+extern void disable_breakpoints_in_shlibs (program_space *pspace);
 
 /* This function returns true if B is a catchpoint.  */
 
diff --git a/gdb/solib.c b/gdb/solib.c
index 0a888430cf9b..98cda039a833 100644
--- a/gdb/solib.c
+++ b/gdb/solib.c
@@ -1187,7 +1187,7 @@ clear_solib (void)
 {
   const solib_ops *ops = gdbarch_so_ops (current_inferior ()->arch ());
 
-  disable_breakpoints_in_shlibs ();
+  disable_breakpoints_in_shlibs (current_program_space);
 
   current_program_space->so_list.clear_and_dispose ([] (solib *so) {
     notify_solib_unloaded (current_program_space, *so);
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index 48b0d10d24c7..7f3044fc61de 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -1906,7 +1906,7 @@ windows_nat_target::do_initial_windows_stuff (DWORD pid, bool attaching)
   inf = current_inferior ();
   if (!inf->target_is_pushed (this))
     inf->push_target (this);
-  disable_breakpoints_in_shlibs ();
+  disable_breakpoints_in_shlibs (current_program_space);
   windows_clear_solib ();
   clear_proceed_status (0);
   init_wait_for_inferior ();
-- 
2.43.0

[PATCH 4/5] gdb: add program_space parameter to clear_solib

[Simon Marchi]

Make the current_program_space reference bubble up one level.

Remove one unnecessary declaration of clear_solib.

Change-Id: I234e2c8c0b71713364fc7b76cee2bee2b026bd6d
---
 gdb/corelow.c |  2 +-
 gdb/solib.c   | 21 ++++++++++++---------
 gdb/solib.h   |  6 +++---
 gdb/symtab.h  |  4 ----
 4 files changed, 16 insertions(+), 17 deletions(-)

diff --git a/gdb/corelow.c b/gdb/corelow.c
index 43c1f69b1317..f291b2aba191 100644
--- a/gdb/corelow.c
+++ b/gdb/corelow.c
@@ -335,7 +335,7 @@ core_target::clear_core ()
 
       /* Clear out solib state while the bfd is still open.  See
 	 comments in clear_solib in solib.c.  */
-      clear_solib ();
+      clear_solib (current_program_space);
 
       current_program_space->cbfd.reset (nullptr);
     }
diff --git a/gdb/solib.c b/gdb/solib.c
index 98cda039a833..bd69c549b8e8 100644
--- a/gdb/solib.c
+++ b/gdb/solib.c
@@ -1180,23 +1180,26 @@ solib_keep_data_in_core (CORE_ADDR vaddr, unsigned long size)
     return false;
 }
 
-/* Called by free_all_symtabs */
+/* See solib.h.  */
 
 void
-clear_solib (void)
+clear_solib (program_space *pspace)
 {
-  const solib_ops *ops = gdbarch_so_ops (current_inferior ()->arch ());
+  inferior *inf = find_inferior_for_program_space (pspace);
+  gdb_assert (inf != nullptr);
+
+  const solib_ops *ops = gdbarch_so_ops (inf->arch ());
 
-  disable_breakpoints_in_shlibs (current_program_space);
+  disable_breakpoints_in_shlibs (pspace);
 
-  current_program_space->so_list.clear_and_dispose ([] (solib *so) {
-    notify_solib_unloaded (current_program_space, *so);
-    current_program_space->remove_target_sections (so);
+  pspace->so_list.clear_and_dispose ([pspace] (solib *so) {
+    notify_solib_unloaded (pspace, *so);
+    pspace->remove_target_sections (so);
     delete so;
   });
 
   if (ops->clear_solib != nullptr)
-    ops->clear_solib (current_program_space);
+    ops->clear_solib (pspace);
 }
 
 /* Shared library startup support.  When GDB starts up the inferior,
@@ -1244,7 +1247,7 @@ no_shared_libraries (const char *ignored, int from_tty)
      access to their associated objfiles.  Therefore, we can not purge the
      solibs' objfiles before clear_solib has been called.  */
 
-  clear_solib ();
+  clear_solib (current_program_space);
   objfile_purge_solibs ();
 }
 
diff --git a/gdb/solib.h b/gdb/solib.h
index 69183278318b..f7a93c0718f0 100644
--- a/gdb/solib.h
+++ b/gdb/solib.h
@@ -42,10 +42,10 @@ extern bool debug_solib;
 #define SOLIB_SCOPED_DEBUG_START_END(fmt, ...) \
   scoped_debug_start_end (debug_solib, "solib", fmt, ##__VA_ARGS__)
 
-/* Called when we free all symtabs, to free the shared library information
-   as well.  */
+/* Called when we free all symtabs of PSPACE, to free the shared library
+   information as well.  */
 
-extern void clear_solib (void);
+extern void clear_solib (program_space *pspace);
 
 /* Called to add symbols from a shared library to gdb's symbol table.  */
 
diff --git a/gdb/symtab.h b/gdb/symtab.h
index 3b067a77b3c8..ca5a5b0f7fde 100644
--- a/gdb/symtab.h
+++ b/gdb/symtab.h
@@ -2423,10 +2423,6 @@ extern bool find_line_pc_range (struct symtab_and_line, CORE_ADDR *,
 
 extern void resolve_sal_pc (struct symtab_and_line *);
 
-/* solib.c */
-
-extern void clear_solib (void);
-
 /* The reason we're calling into a completion match list collector
    function.  */
 enum class complete_symbol_mode
-- 
2.43.0

Re: [PATCH 4/5] gdb: add program_space parameter to clear_solib

[Simon Marchi]

On 2/6/24 12:14, Simon Marchi wrote:
> Make the current_program_space reference bubble up one level.
> 
> Remove one unnecessary declaration of clear_solib.
> 
> Change-Id: I234e2c8c0b71713364fc7b76cee2bee2b026bd6d
> ---
>  gdb/corelow.c |  2 +-
>  gdb/solib.c   | 21 ++++++++++++---------
>  gdb/solib.h   |  6 +++---
>  gdb/symtab.h  |  4 ----
>  4 files changed, 16 insertions(+), 17 deletions(-)
> 
> diff --git a/gdb/corelow.c b/gdb/corelow.c
> index 43c1f69b1317..f291b2aba191 100644
> --- a/gdb/corelow.c
> +++ b/gdb/corelow.c
> @@ -335,7 +335,7 @@ core_target::clear_core ()
>  
>        /* Clear out solib state while the bfd is still open.  See
>  	 comments in clear_solib in solib.c.  */
> -      clear_solib ();
> +      clear_solib (current_program_space);
>  
>        current_program_space->cbfd.reset (nullptr);
>      }
> diff --git a/gdb/solib.c b/gdb/solib.c
> index 98cda039a833..bd69c549b8e8 100644
> --- a/gdb/solib.c
> +++ b/gdb/solib.c
> @@ -1180,23 +1180,26 @@ solib_keep_data_in_core (CORE_ADDR vaddr, unsigned long size)
>      return false;
>  }
>  
> -/* Called by free_all_symtabs */
> +/* See solib.h.  */
>  
>  void
> -clear_solib (void)
> +clear_solib (program_space *pspace)
>  {
> -  const solib_ops *ops = gdbarch_so_ops (current_inferior ()->arch ());
> +  inferior *inf = find_inferior_for_program_space (pspace);
> +  gdb_assert (inf != nullptr);

Thanks to the Linaro CI for pointing it out, this particular change
causes some regressions, for instance in gdb.base/catch-fork-kill.exp.
The assertion fails because inf is nullptr.

We're here:

    #0  internal_error_loc (file=0x55adc73f51c0 "/home/smarchi/src/binutils-gdb/gdb/solib.c", line=1189,
        fmt=0x55adc73f4b00 "%s: Assertion `%s' failed.") at /home/smarchi/src/binutils-gdb/gdbsupport/errors.cc:57
    #1  0x000055adcb297e6d in clear_solib (pspace=0x613000011d80) at /home/smarchi/src/binutils-gdb/gdb/solib.c:1189
    #2  0x000055adcb29822e in no_shared_libraries (ignored=0x0, from_tty=0) at /home/smarchi/src/binutils-gdb/gdb/solib.c:1250
    #3  0x000055adca9f26d4 in program_space::~program_space (this=0x613000011d80, __in_chrg=<optimized out>)
        at /home/smarchi/src/binutils-gdb/gdb/progspace.c:120
    #4  0x000055adca0c570c in delete_inferior (inf=0x618000225480) at /home/smarchi/src/binutils-gdb/gdb/inferior.c:302
    #5  0x000055adca0c801d in prune_inferiors () at /home/smarchi/src/binutils-gdb/gdb/inferior.c:492

What I observe is that the current inferior is #1, bound to pspace #1,
and we're deleting inferior #2, bound to pspace #2.  My change doesn't
work, because at this point inferior #2 has been removed from the
inferior list, so find_inferior_for_program_space returns nullptr.

However, the current code seems wrong too, because we're using inferior
#1's arch to get hold of an solib_ops to call ops->clear_solib on,
despite deleting program space #2, which was bound to inferior #2.  It
works here, because both inferiors have the same gdbarch with the same
solib_ops.  But it would be possible for the two inferiors to have
different gdbarches and solib_ops.

My upcoming solib series should improve the situation, by having a
backlink from program_space to solib_ops.  So we won't need an inferior
here in order to get the solib_ops.  In the mean time, I'll try to
revert using current_inferior to get the arch and solib_ops, even though
I know it's wrong.

Simon

[PATCH 5/5] gdb: remove unnecessary nullptr check in remove_user_added_objfile

[Simon Marchi]

Since commit 74daa597e74 ("gdb: add all_objfiles_removed observer"), the
objfile passed to the free_objfile observable can't be nullptr.

Change-Id: If215aa051ab43c068b11746938022c7efca09caa
---
 gdb/solib.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb/solib.c b/gdb/solib.c
index bd69c549b8e8..3eb84d814a20 100644
--- a/gdb/solib.c
+++ b/gdb/solib.c
@@ -1698,7 +1698,7 @@ gdb_bfd_lookup_symbol (bfd *abfd,
 static void
 remove_user_added_objfile (struct objfile *objfile)
 {
-  if (objfile != 0 && objfile->flags & OBJF_USERLOADED)
+  if (objfile->flags & OBJF_USERLOADED)
     {
       for (solib &so : objfile->pspace->solibs ())
 	if (so.objfile == objfile)
-- 
2.43.0