[PATCH] symfile, vdso: remove target sections

[PATCH] symfile, vdso: remove target sections

[Markus Metzger]

Target sections added by the add-symbol-file-from-memory command are not
removed when the process exits.  In fact, they are not removed, at all.

This causes GDB to crash in gdb.base/break-interp.exp.

Change the owner of those target sections to the object file generated in
symbol_file_add_from_memory and generalize the free_objfile observer in
symfile.c to remove target sections of any freed object file.

2014-06-04  Markus Metzger  <markus.t.metzger@intel.com>

	* symfile.c (symfile_free_objfile): Remove restriction to
	OBJF_USERLOADED.
	* symfile-mem.c (symbol_file_add_from_memory): Call
	add_target_sections_of_objfile.
---
 gdb/symfile-mem.c | 18 +-----------------
 gdb/symfile.c     |  2 +-
 2 files changed, 2 insertions(+), 18 deletions(-)

diff --git a/gdb/symfile-mem.c b/gdb/symfile-mem.c
index b29421e..ef48f7d 100644
--- a/gdb/symfile-mem.c
+++ b/gdb/symfile-mem.c
@@ -92,7 +92,6 @@ symbol_file_add_from_memory (struct bfd *templ, CORE_ADDR addr,
   struct section_addr_info *sai;
   unsigned int i;
   struct cleanup *cleanup;
-  struct target_section *sections, *sections_end, *tsec;
 
   if (bfd_get_flavour (templ) != bfd_target_elf_flavour)
     error (_("add-symbol-file-from-memory not supported for this target"));
@@ -132,22 +131,7 @@ symbol_file_add_from_memory (struct bfd *templ, CORE_ADDR addr,
 				   from_tty ? SYMFILE_VERBOSE : 0,
                                    sai, OBJF_SHARED, NULL);
 
-  sections = NULL;
-  sections_end = NULL;
-
-  if (build_section_table (nbfd, &sections, &sections_end) == 0)
-    {
-      make_cleanup (xfree, sections);
-
-      /* Adjust the target section addresses by the load address.  */
-      for (tsec = sections; tsec != sections_end; ++tsec)
-	{
-	  tsec->addr += loadbase;
-	  tsec->endaddr += loadbase;
-	}
-
-      add_target_sections (&nbfd, sections, sections_end);
-    }
+  add_target_sections_of_objfile (objf);
 
   /* This might change our ideas about frames already looked at.  */
   reinit_frame_cache ();
diff --git a/gdb/symfile.c b/gdb/symfile.c
index 64a83c6..caa0722 100644
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -3893,7 +3893,7 @@ static void
 symfile_free_objfile (struct objfile *objfile)
 {
   /* Remove the target sections of user-added objfiles.  */
-  if (objfile != 0 && objfile->flags & OBJF_USERLOADED)
+  if (objfile != NULL)
     remove_target_sections ((void *) objfile);
 }
 
-- 
1.8.3.1

Re: [PATCH] symfile, vdso: remove target sections

[Pedro Alves]

On 06/04/2014 01:31 PM, Markus Metzger wrote:

> diff --git a/gdb/symfile.c b/gdb/symfile.c
> index 64a83c6..caa0722 100644
> --- a/gdb/symfile.c
> +++ b/gdb/symfile.c
> @@ -3893,7 +3893,7 @@ static void
>  symfile_free_objfile (struct objfile *objfile)
>  {
>    /* Remove the target sections of user-added objfiles.  */

This comment is now stale.  How about:

    /* Remove the target sections owned by this objfile.  */

?

Otherwise OK.

Thanks!

-- 
Pedro Alves