[PATCH] elf: Always ignore SHF_EXCLUDE for relocatable link

[Alan Modra]

On Fri, Mar 19, 2021 at 07:52:50AM -0700, H.J. Lu via Binutils wrote:
> --- a/ld/ldlang.c
> +++ b/ld/ldlang.c
> @@ -7566,6 +7566,7 @@ lang_gc_sections (void)
>  
>    /* SEC_EXCLUDE is ignored when doing a relocatable link, except in
>       the special case of debug info.  (See bfd/stabs.c)

The exception for debug sections in clearing SEC_EXCLUDE when
relocatable was really for one specific debug section, so let's make
it do just that.

bfd/
	PR 27590
	* elf.c (_bfd_elf_make_section_from_shdr): Remove SHF_EXCLUDE
	test for .gnu.debuglto*.
ld/
	PR 27590
	* ldlang.c (lang_gc_sections): Clear SEC_EXCLUDE when relocatable
	for all sections except .stabstr.

diff --git a/bfd/elf.c b/bfd/elf.c
index 7bd12dfbf3..381951da12 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -1085,10 +1085,7 @@ _bfd_elf_make_section_from_shdr (bfd *abfd,
       if (name [0] == '.')
 	{
 	  if (strncmp (name, ".debug", 6) == 0
-	      /* NB: Treate .gnu.debuglto_.debug_ section as debugging
-		 section unless it is marked with SHF_EXCLUDE.  */
-	      || ((flags & SEC_EXCLUDE) == 0
-		  && strncmp (name, ".gnu.debuglto_.debug_", 21) == 0)
+	      || strncmp (name, ".gnu.debuglto_.debug_", 21) == 0
 	      || strncmp (name, ".gnu.linkonce.wi.", 17) == 0
 	      || strncmp (name, ".zdebug", 7) == 0)
 	    flags |= SEC_DEBUGGING | SEC_ELF_OCTETS;
diff --git a/ld/ldlang.c b/ld/ldlang.c
index 684e1d23a2..df8a5d17ac 100644
--- a/ld/ldlang.c
+++ b/ld/ldlang.c
@@ -7565,7 +7565,7 @@ lang_gc_sections (void)
   lang_gc_sections_1 (statement_list.head);
 
   /* SEC_EXCLUDE is ignored when doing a relocatable link, except in
-     the special case of debug info.  (See bfd/stabs.c)
+     the special case of .stabstr debug info.  (See bfd/stabs.c)
      Twiddle the flag here, to simplify later linker code.  */
   if (bfd_link_relocatable (&link_info))
     {
@@ -7577,7 +7577,8 @@ lang_gc_sections (void)
 	    continue;
 #endif
 	  for (sec = f->the_bfd->sections; sec != NULL; sec = sec->next)
-	    if ((sec->flags & SEC_DEBUGGING) == 0)
+	    if ((sec->flags & SEC_DEBUGGING) == 0
+		|| strcmp (sec->name, ".stabstr") != 0)
 	      sec->flags &= ~SEC_EXCLUDE;
 	}
     }


-- 
Alan Modra
Australia Development Lab, IBM