Handle STT_GNU_IFUNC symols when building shared library.

bfd/

2012-05-25  H.J. Lu  <hongjiu.lu@intel.com>

	Backport from mainline
	2012-01-06  H.J. Lu  <hongjiu.lu@intel.com>

	PR ld/12366
	PR ld/12371
	* elf-ifunc.c (_bfd_elf_allocate_ifunc_dyn_relocs): Properly
	handle symbols marked with regular reference, but not non-GOT
	reference when building shared library.

	* elf32-i386.c (elf_i386_gc_sweep_hook): Properly handle
	local and global STT_GNU_IFUNC symols when building shared
	library.
	* elf64-x86-64.c (elf_x86_64_gc_sweep_hook): Likewise.

ld/testsuite/

2012-05-25  H.J. Lu  <hongjiu.lu@intel.com>

	Backport from mainline
	2012-01-06  H.J. Lu  <hongjiu.lu@intel.com>

	PR ld/12366
	PR ld/12371
	* ld-ifunc/ifunc-10-i386.s: Add more tests.
	* ld-ifunc/ifunc-10-x86-64.s: Likewise.
	* ld-ifunc/ifunc-11-i386.s: Likewise.
	* ld-ifunc/ifunc-11-x86-64.s: Likewise.

	* ld-ifunc/ifunc-12-i386.d: New.
	* ld-ifunc/ifunc-12-i386.s: Likewise.
	* ld-ifunc/ifunc-12-x86-64.d: Likewise.
	* ld-ifunc/ifunc-12-x86-64.s: Likewise.
	* ld-ifunc/ifunc-13-i386.d: Likewise.
	* ld-ifunc/ifunc-13-x86-64.d: Likewise.
	* ld-ifunc/ifunc-13a-i386.s: Likewise.
	* ld-ifunc/ifunc-13a-x86-64.s: Likewise.
	* ld-ifunc/ifunc-13b-i386.s: Likewise.
	* ld-ifunc/ifunc-13b-x86-64.s: Likewise.

4 files changed, 77 insertions, 33 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 64bdff6c93..bcc02f3bf1 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,19 @@
+2012-05-25  H.J. Lu  <hongjiu.lu@intel.com>
+
+	Backport from mainline
+	2012-01-06  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/12366
+	PR ld/12371
+	* elf-ifunc.c (_bfd_elf_allocate_ifunc_dyn_relocs): Properly
+	handle symbols marked with regular reference, but not non-GOT
+	reference when building shared library.
+
+	* elf32-i386.c (elf_i386_gc_sweep_hook): Properly handle
+	local and global STT_GNU_IFUNC symols when building shared
+	library.
+	* elf64-x86-64.c (elf_x86_64_gc_sweep_hook): Likewise.
+
 2011-05-23  DJ Delorie  <dj@redhat.com>
 
 	* elf32-rx.c (rx_elf_object_p): When reading an RX object in, undo
diff --git a/bfd/elf-ifunc.c b/bfd/elf-ifunc.c
index 760fc26c1a..17b23c2ffc 100644
--- a/bfd/elf-ifunc.c
+++ b/bfd/elf-ifunc.c
@@ -190,10 +190,29 @@ _bfd_elf_allocate_ifunc_dyn_relocs (struct bfd_link_info *info,
   /* Support garbage collection against STT_GNU_IFUNC symbols.  */
   if (h->plt.refcount <= 0 && h->got.refcount <= 0)
     {
-      h->got = htab->init_got_offset;
-      h->plt = htab->init_plt_offset;
-      *head = NULL;
-      return TRUE;
+      /* When building shared library, we need to handle the case
+         where it is marked with regular reference, but not non-GOT
+	 reference.  It may happen if we didn't see STT_GNU_IFUNC
+	 symbol at the time when checking relocations.  */
+      bfd_size_type count = 0;
+
+      if (info->shared
+	  && !h->non_got_ref
+	  && h->ref_regular)
+	{
+	  for (p = *head; p != NULL; p = p->next)
+	    count += p->count;
+	  if (count != 0)
+	    h->non_got_ref = 1;
+	}
+
+      if (count == 0)
+	{
+	  h->got = htab->init_got_offset;
+	  h->plt = htab->init_plt_offset;
+	  *head = NULL;
+	  return TRUE;
+	}
     }
 
   /* Return and discard space for dynamic relocations against it if
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index 1071f015d0..bd349e1083 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -1807,23 +1807,10 @@ elf_i386_gc_sweep_hook (bfd *abfd,
       r_symndx = ELF32_R_SYM (rel->r_info);
       if (r_symndx >= symtab_hdr->sh_info)
 	{
-	  struct elf_i386_link_hash_entry *eh;
-	  struct elf_dyn_relocs **pp;
-	  struct elf_dyn_relocs *p;
-
 	  h = sym_hashes[r_symndx - symtab_hdr->sh_info];
 	  while (h->root.type == bfd_link_hash_indirect
 		 || h->root.type == bfd_link_hash_warning)
 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
-	  eh = (struct elf_i386_link_hash_entry *) h;
-
-	  for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
-	    if (p->sec == sec)
-	      {
-		/* Everything must go for SEC.  */
-		*pp = p->next;
-		break;
-	      }
 	}
       else
 	{
@@ -1843,6 +1830,22 @@ elf_i386_gc_sweep_hook (bfd *abfd,
 	    }
 	}
 
+      if (h)
+	{
+	  struct elf_i386_link_hash_entry *eh;
+	  struct elf_dyn_relocs **pp;
+	  struct elf_dyn_relocs *p;
+
+	  eh = (struct elf_i386_link_hash_entry *) h;
+	  for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
+	    if (p->sec == sec)
+	      {
+		/* Everything must go for SEC.  */
+		*pp = p->next;
+		break;
+	      }
+	}
+
       r_type = ELF32_R_TYPE (rel->r_info);
       if (! elf_i386_tls_transition (info, abfd, sec, NULL,
 				     symtab_hdr, sym_hashes,
@@ -1883,7 +1886,8 @@ elf_i386_gc_sweep_hook (bfd *abfd,
 
 	case R_386_32:
 	case R_386_PC32:
-	  if (info->shared)
+	  if (info->shared
+	      && (h == NULL || h->type != STT_GNU_IFUNC))
 	    break;
 	  /* Fall through */
 
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index 09af249dfe..04c74550be 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -1645,23 +1645,10 @@ elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
       r_symndx = ELF64_R_SYM (rel->r_info);
       if (r_symndx >= symtab_hdr->sh_info)
 	{
-	  struct elf64_x86_64_link_hash_entry *eh;
-	  struct elf_dyn_relocs **pp;
-	  struct elf_dyn_relocs *p;
-
 	  h = sym_hashes[r_symndx - symtab_hdr->sh_info];
 	  while (h->root.type == bfd_link_hash_indirect
 		 || h->root.type == bfd_link_hash_warning)
 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
-	  eh = (struct elf64_x86_64_link_hash_entry *) h;
-
-	  for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
-	    if (p->sec == sec)
-	      {
-		/* Everything must go for SEC.  */
-		*pp = p->next;
-		break;
-	      }
 	}
       else
 	{
@@ -1682,7 +1669,24 @@ elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
 	    }
 	}
 
-      r_type = ELF64_R_TYPE (rel->r_info);
+      if (h)
+	{
+	  struct elf64_x86_64_link_hash_entry *eh;
+	  struct elf_dyn_relocs **pp;
+	  struct elf_dyn_relocs *p;
+
+	  eh = (struct elf64_x86_64_link_hash_entry *) h;
+
+	  for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
+	    if (p->sec == sec)
+	      {
+		/* Everything must go for SEC.  */
+		*pp = p->next;
+		break;
+	      }
+	}
+
+      r_type = ELF32_R_TYPE (rel->r_info);
       if (! elf64_x86_64_tls_transition (info, abfd, sec, NULL,
 					 symtab_hdr, sym_hashes,
 					 &r_type, GOT_UNKNOWN,
@@ -1733,7 +1737,8 @@ elf64_x86_64_gc_sweep_hook (bfd *abfd, struct bfd_link_info *info,
 	case R_X86_64_PC16:
 	case R_X86_64_PC32:
 	case R_X86_64_PC64:
-	  if (info->shared)
+	  if (info->shared
+	      && (h == NULL || h->type != STT_GNU_IFUNC))
 	    break;
 	  /* Fall thru */