[binutils-gdb] PR22451, strip no longer works on older object files

[Alan Modra <amodra at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=28e07a0510ca896311014cddf125aedfd7a8cd52

commit 28e07a0510ca896311014cddf125aedfd7a8cd52
Author: Alan Modra <amodra@gmail.com>
Date:   Mon Nov 20 21:35:09 2017 +1030

    PR22451, strip no longer works on older object files
    
    Setting SHF_GROUP unconditionally on rel/rela sections associated with
    SHF_GROUP sections fails badly with objcopy/strip and ld -r if the
    input file SHT_GROUP section didn't specify the rel/rela sections.
    This patch rearranges where SHF_GROUP is set for rel/rela sections.
    
    	PR 22451
    	PR 22460
    	* elf.c (_bfd_elf_init_reloc_shdr): Delete "sec_hdr" parameter
    	and leave rel_hdr->sh_flags zero.  Update calls.
    	(bfd_elf_set_group_contents): Check input rel/rela SHF_GROUP
    	flag when !gas before adding rel/rela section to group.  Set
    	output rel/rela SHF_GROUP flags.

Diff:
---
 bfd/ChangeLog | 10 ++++++++++
 bfd/elf.c     | 22 +++++++++++++++-------
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 485371a..6e148b0 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,13 @@
+2017-11-20  Alan Modra  <amodra@gmail.com>
+
+	PR 22451
+	PR 22460
+	* elf.c (_bfd_elf_init_reloc_shdr): Delete "sec_hdr" parameter
+	and leave rel_hdr->sh_flags zero.  Update calls.
+	(bfd_elf_set_group_contents): Check input rel/rela SHF_GROUP
+	flag when !gas before adding rel/rela section to group.  Set
+	output rel/rela SHF_GROUP flags.
+
 2017-11-18  Jim Wilson  <jimw@sifive.com>
 
 	* elfnn-riscv.c (_bfd_riscv_relax_align): Add space between alignment
diff --git a/bfd/elf.c b/bfd/elf.c
index 93ed443..8cd67ad 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -3061,7 +3061,6 @@ _bfd_elf_set_reloc_sh_name (bfd *abfd,
 static bfd_boolean
 _bfd_elf_init_reloc_shdr (bfd *abfd,
 			  struct bfd_elf_section_reloc_data *reldata,
-			  const Elf_Internal_Shdr *sec_hdr,
 			  const char *sec_name,
 			  bfd_boolean use_rela_p,
 			  bfd_boolean delay_st_name_p)
@@ -3083,7 +3082,7 @@ _bfd_elf_init_reloc_shdr (bfd *abfd,
 			 ? bed->s->sizeof_rela
 			 : bed->s->sizeof_rel);
   rel_hdr->sh_addralign = (bfd_vma) 1 << bed->s->log_file_align;
-  rel_hdr->sh_flags = sec_hdr->sh_flags & SHF_GROUP;
+  rel_hdr->sh_flags = 0;
   rel_hdr->sh_addr = 0;
   rel_hdr->sh_size = 0;
   rel_hdr->sh_offset = 0;
@@ -3374,14 +3373,14 @@ elf_fake_sections (bfd *abfd, asection *asect, void *fsarg)
 	      || arg->link_info->emitrelocations))
 	{
 	  if (esd->rel.count && esd->rel.hdr == NULL
-	      && !_bfd_elf_init_reloc_shdr (abfd, &esd->rel, this_hdr, name,
+	      && !_bfd_elf_init_reloc_shdr (abfd, &esd->rel, name,
 					    FALSE, delay_st_name_p))
 	    {
 	      arg->failed = TRUE;
 	      return;
 	    }
 	  if (esd->rela.count && esd->rela.hdr == NULL
-	      && !_bfd_elf_init_reloc_shdr (abfd, &esd->rela, this_hdr, name,
+	      && !_bfd_elf_init_reloc_shdr (abfd, &esd->rela, name,
 					    TRUE, delay_st_name_p))
 	    {
 	      arg->failed = TRUE;
@@ -3391,7 +3390,6 @@ elf_fake_sections (bfd *abfd, asection *asect, void *fsarg)
       else if (!_bfd_elf_init_reloc_shdr (abfd,
 					  (asect->use_rela_p
 					   ? &esd->rela : &esd->rel),
-					  this_hdr,
 					  name,
 					  asect->use_rela_p,
 					  delay_st_name_p))
@@ -3526,13 +3524,23 @@ bfd_elf_set_group_contents (bfd *abfd, asection *sec, void *failedptrarg)
 	  && !bfd_is_abs_section (s))
 	{
 	  struct bfd_elf_section_data *elf_sec = elf_section_data (s);
-	  if (elf_sec->rel.hdr != NULL)
+	  struct bfd_elf_section_data *input_elf_sec = elf_section_data (elt);
+
+	  if (elf_sec->rel.hdr != NULL
+	      && (gas
+		  || (input_elf_sec->rel.hdr != NULL
+		      && input_elf_sec->rel.hdr->sh_flags & SHF_GROUP) != 0))
 	    {
+	      elf_sec->rel.hdr->sh_flags |= SHF_GROUP;
 	      loc -= 4;
 	      H_PUT_32 (abfd, elf_sec->rel.idx, loc);
 	    }
-	  if (elf_sec->rela.hdr != NULL)
+	  if (elf_sec->rela.hdr != NULL
+	      && (gas
+		  || (input_elf_sec->rela.hdr != NULL
+		      && input_elf_sec->rela.hdr->sh_flags & SHF_GROUP) != 0))
 	    {
+	      elf_sec->rela.hdr->sh_flags |= SHF_GROUP;
 	      loc -= 4;
 	      H_PUT_32 (abfd, elf_sec->rela.idx, loc);
 	    }