ld: Unify STT_GNU_IFUNC handling

Take STT_GNU_IFUNC handling scattered across targets and gather it in
the generic ELF linker.

bfd/

	PR ld/23238
	* elf-s390-common.c (elf_s390_add_symbol_hook): Removed.
	* elf32-arc.c (elf_arc_add_symbol_hook): Likewise.
	(elf_backend_add_symbol_hook): Likewise.
	* elf32-m68k.c (elf_m68k_add_symbol_hook): Likewise.
	(elf_backend_add_symbol_hook): Likewise.
	* elf32-s390.c (elf_backend_add_symbol_hook): Likewise.
	* elf32-sparc.c (elf32_sparc_add_symbol_hook): Likewise.
	(elf_backend_add_symbol_hook): Likewise.
	* elf64-s390.c (elf_backend_add_symbol_hook): Likewise.
	* elfxx-aarch64.c (_bfd_aarch64_elf_add_symbol_hook): Likewise.
	* elfxx-aarch64.h (_bfd_aarch64_elf_add_symbol_hook): Likewise.
	(elf_backend_add_symbol_hook): Likewise.
	* elf32-arm.c (elf32_arm_add_symbol_hook): Remove STT_GNU_IFUNC
	handling.
	* elf32-ppc.c (ppc_elf_add_symbol_hook): Likewise.
	* elf64-ppc.c (ppc64_elf_add_symbol_hook): Likewise.
	* elf64-sparc.c (elf64_sparc_add_symbol_hook): Likewise.
	* elflink.c (elf_link_add_object_symbols): Set
	elf_gnu_symbol_ifunc for STT_GNU_IFUNC symbols.

ld/

	PR ld/23238
	* testsuite/ld-ifunc/ifunc-26.d: New file.
	* testsuite/ld-ifunc/ifunc-26.s: Likewise.
	* testsuite/ld-ifunc/ifunc.exp: Run *.d tests without a
	working compiler.

14 files changed, 34 insertions, 133 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 0419bec..f190b9f 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,26 @@
+2018-05-28  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/23238
+	* elf-s390-common.c (elf_s390_add_symbol_hook): Removed.
+	* elf32-arc.c (elf_arc_add_symbol_hook): Likewise.
+	(elf_backend_add_symbol_hook): Likewise.
+	* elf32-m68k.c (elf_m68k_add_symbol_hook): Likewise.
+	(elf_backend_add_symbol_hook): Likewise.
+	* elf32-s390.c (elf_backend_add_symbol_hook): Likewise.
+	* elf32-sparc.c (elf32_sparc_add_symbol_hook): Likewise.
+	(elf_backend_add_symbol_hook): Likewise.
+	* elf64-s390.c (elf_backend_add_symbol_hook): Likewise.
+	* elfxx-aarch64.c (_bfd_aarch64_elf_add_symbol_hook): Likewise.
+	* elfxx-aarch64.h (_bfd_aarch64_elf_add_symbol_hook): Likewise.
+	(elf_backend_add_symbol_hook): Likewise.
+	* elf32-arm.c (elf32_arm_add_symbol_hook): Remove STT_GNU_IFUNC
+	handling.
+	* elf32-ppc.c (ppc_elf_add_symbol_hook): Likewise.
+	* elf64-ppc.c (ppc64_elf_add_symbol_hook): Likewise.
+	* elf64-sparc.c (elf64_sparc_add_symbol_hook): Likewise.
+	* elflink.c (elf_link_add_object_symbols): Set
+	elf_gnu_symbol_ifunc for STT_GNU_IFUNC symbols.
+
 2018-05-26  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR ld/23194
diff --git a/bfd/elf-s390-common.c b/bfd/elf-s390-common.c
index 21195f2..b37cb25 100644
--- a/bfd/elf-s390-common.c
+++ b/bfd/elf-s390-common.c
@@ -223,25 +223,6 @@ elf_s390_allocate_local_syminfo (bfd *abfd, Elf_Internal_Shdr *symtab_hdr)
   return TRUE;
 }
 
-/* Pick ELFOSABI_GNU if IFUNC symbols are used.  */
-
-static bfd_boolean
-elf_s390_add_symbol_hook (bfd *abfd,
-			  struct bfd_link_info *info,
-			  Elf_Internal_Sym *sym,
-			  const char **namep ATTRIBUTE_UNUSED,
-			  flagword *flagsp ATTRIBUTE_UNUSED,
-			  asection **secp ATTRIBUTE_UNUSED,
-			  bfd_vma *valp ATTRIBUTE_UNUSED)
-{
-  if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
-      && (abfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-
-  return TRUE;
-}
-
 /* Whether to sort relocs output by ld -r or ld --emit-relocs, by
    r_offset.  Don't do so for code sections.  We want to keep ordering
    of GDCALL / PLT32DBL for TLS optimizations as is.  On the other
diff --git a/bfd/elf32-arc.c b/bfd/elf32-arc.c
index 33fff58..a48ef0c 100644
--- a/bfd/elf32-arc.c
+++ b/bfd/elf32-arc.c
@@ -2797,26 +2797,6 @@ const struct elf_size_info arc_elf32_size_info =
 
 #define elf_backend_size_info		arc_elf32_size_info
 
-/* Hook called by the linker routine which adds symbols from an object
-   file.  */
-
-static bfd_boolean
-elf_arc_add_symbol_hook (bfd * abfd,
-			 struct bfd_link_info * info,
-			 Elf_Internal_Sym * sym,
-			 const char ** namep ATTRIBUTE_UNUSED,
-			 flagword * flagsp ATTRIBUTE_UNUSED,
-			 asection ** secp ATTRIBUTE_UNUSED,
-			 bfd_vma * valp ATTRIBUTE_UNUSED)
-{
-  if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
-      && (abfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-
-  return TRUE;
-}
-
 /* GDB expects general purpose registers to be in section .reg.  However Linux
    kernel doesn't create this section and instead writes registers to NOTE
    section.  It is up to the binutils to create a pseudo-section .reg from the
@@ -2946,7 +2926,6 @@ elf32_arc_section_from_shdr (bfd *abfd,
 
 #define elf_backend_finish_dynamic_sections  elf_arc_finish_dynamic_sections
 #define elf_backend_size_dynamic_sections    elf_arc_size_dynamic_sections
-#define elf_backend_add_symbol_hook	     elf_arc_add_symbol_hook
 
 #define elf_backend_can_gc_sections	1
 #define elf_backend_want_got_plt	1
diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c
index 5a3b58f..dbfd838 100644
--- a/bfd/elf32-arm.c
+++ b/bfd/elf32-arm.c
@@ -19753,11 +19753,6 @@ elf32_arm_add_symbol_hook (bfd *abfd, struct bfd_link_info *info,
 			   Elf_Internal_Sym *sym, const char **namep,
 			   flagword *flagsp, asection **secp, bfd_vma *valp)
 {
-  if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
-      && (abfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-
   if (elf32_arm_hash_table (info) == NULL)
     return FALSE;
 
diff --git a/bfd/elf32-m68k.c b/bfd/elf32-m68k.c
index 8680504..70532c2 100644
--- a/bfd/elf32-m68k.c
+++ b/bfd/elf32-m68k.c
@@ -4589,26 +4589,6 @@ elf_m68k_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
   return TRUE;
 }
 
-/* Hook called by the linker routine which adds symbols from an object
-   file.  */
-
-static bfd_boolean
-elf_m68k_add_symbol_hook (bfd *abfd,
-			  struct bfd_link_info *info,
-			  Elf_Internal_Sym *sym,
-			  const char **namep ATTRIBUTE_UNUSED,
-			  flagword *flagsp ATTRIBUTE_UNUSED,
-			  asection **secp ATTRIBUTE_UNUSED,
-			  bfd_vma *valp ATTRIBUTE_UNUSED)
-{
-  if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
-      && (abfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-
-  return TRUE;
-}
-
 #define TARGET_BIG_SYM			m68k_elf32_vec
 #define TARGET_BIG_NAME			"elf32-m68k"
 #define ELF_MACHINE_CODE		EM_68K
@@ -4646,7 +4626,6 @@ elf_m68k_add_symbol_hook (bfd *abfd,
 #define elf_backend_object_p		elf32_m68k_object_p
 #define elf_backend_grok_prstatus	elf_m68k_grok_prstatus
 #define elf_backend_grok_psinfo		elf_m68k_grok_psinfo
-#define elf_backend_add_symbol_hook	elf_m68k_add_symbol_hook
 
 #define elf_backend_can_gc_sections 1
 #define elf_backend_can_refcount 1
diff --git a/bfd/elf32-ppc.c b/bfd/elf32-ppc.c
index 462c8af..3482bac 100644
--- a/bfd/elf32-ppc.c
+++ b/bfd/elf32-ppc.c
@@ -3792,11 +3792,6 @@ ppc_elf_add_symbol_hook (bfd *abfd,
       *valp = sym->st_size;
     }
 
-  if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
-      && (abfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-
   return TRUE;
 }
 
diff --git a/bfd/elf32-s390.c b/bfd/elf32-s390.c
index b3603bd..99ceb76 100644
--- a/bfd/elf32-s390.c
+++ b/bfd/elf32-s390.c
@@ -4049,7 +4049,6 @@ elf32_s390_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info)
 #define elf_backend_grok_psinfo		      elf_s390_grok_psinfo
 #define elf_backend_write_core_note	      elf_s390_write_core_note
 #define elf_backend_plt_sym_val		      elf_s390_plt_sym_val
-#define elf_backend_add_symbol_hook	      elf_s390_add_symbol_hook
 #define elf_backend_sort_relocs_p	      elf_s390_elf_sort_relocs_p
 
 #define bfd_elf32_mkobject		elf_s390_mkobject
diff --git a/bfd/elf32-sparc.c b/bfd/elf32-sparc.c
index 1a18e1e..4378b61 100644
--- a/bfd/elf32-sparc.c
+++ b/bfd/elf32-sparc.c
@@ -175,25 +175,6 @@ elf32_sparc_reloc_type_class (const struct bfd_link_info *info ATTRIBUTE_UNUSED,
     }
 }
 
-/* Hook called by the linker routine which adds symbols from an object
-   file.  */
-
-static bfd_boolean
-elf32_sparc_add_symbol_hook (bfd * abfd,
-			     struct bfd_link_info * info,
-			     Elf_Internal_Sym * sym,
-			     const char ** namep ATTRIBUTE_UNUSED,
-			     flagword * flagsp ATTRIBUTE_UNUSED,
-			     asection ** secp ATTRIBUTE_UNUSED,
-			     bfd_vma * valp ATTRIBUTE_UNUSED)
-{
-  if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
-      && (abfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-  return TRUE;
-}
-
 #define TARGET_BIG_SYM	sparc_elf32_vec
 #define TARGET_BIG_NAME	"elf32-sparc"
 #define ELF_ARCH	bfd_arch_sparc
@@ -249,8 +230,6 @@ elf32_sparc_add_symbol_hook (bfd * abfd,
 #define elf_backend_want_dynrelro 1
 #define elf_backend_rela_normal 1
 
-#define elf_backend_add_symbol_hook		elf32_sparc_add_symbol_hook
-
 #define elf_backend_linux_prpsinfo32_ugid16	TRUE
 
 #include "elf32-target.h"
diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index 7f7a8f7..f543cb0 100644
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -5034,11 +5034,6 @@ ppc64_elf_add_symbol_hook (bfd *ibfd,
 			   asection **sec,
 			   bfd_vma *value)
 {
-  if (ELF_ST_TYPE (isym->st_info) == STT_GNU_IFUNC
-      && (ibfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-
   if (*sec != NULL
       && strcmp ((*sec)->name, ".opd") == 0)
     {
diff --git a/bfd/elf64-s390.c b/bfd/elf64-s390.c
index bfa0234..612557f 100644
--- a/bfd/elf64-s390.c
+++ b/bfd/elf64-s390.c
@@ -3962,7 +3962,6 @@ const struct elf_size_info s390_elf64_size_info =
 #define elf_backend_grok_psinfo		      elf_s390_grok_psinfo
 #define elf_backend_write_core_note	      elf_s390_write_core_note
 #define elf_backend_plt_sym_val		      elf_s390_plt_sym_val
-#define elf_backend_add_symbol_hook	      elf_s390_add_symbol_hook
 #define elf_backend_sort_relocs_p	      elf_s390_elf_sort_relocs_p
 #define elf_backend_additional_program_headers elf_s390_additional_program_headers
 #define elf_backend_modify_segment_map	      elf_s390_modify_segment_map
diff --git a/bfd/elf64-sparc.c b/bfd/elf64-sparc.c
index b4c0475..8c45d32 100644
--- a/bfd/elf64-sparc.c
+++ b/bfd/elf64-sparc.c
@@ -444,11 +444,6 @@ elf64_sparc_add_symbol_hook (bfd *abfd, struct bfd_link_info *info,
 {
   static const char *const stt_types[] = { "NOTYPE", "OBJECT", "FUNCTION" };
 
-  if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
-      && (abfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-
   if (ELF_ST_TYPE (sym->st_info) == STT_REGISTER)
     {
       int reg;
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 05664b4..9dfd3e9 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -4680,10 +4680,17 @@ error_free_dyn:
 	      (struct bfd_link_hash_entry **) sym_hash)))
 	goto error_free_vers;
 
-      if ((flags & BSF_GNU_UNIQUE)
-	  && (abfd->flags & DYNAMIC) == 0
-	  && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-	elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_unique;
+      if ((abfd->flags & DYNAMIC) == 0
+	  && (bfd_get_flavour (info->output_bfd)
+	      == bfd_target_elf_flavour))
+	{
+	  if (ELF_ST_TYPE (isym->st_info) == STT_GNU_IFUNC)
+	    elf_tdata (info->output_bfd)->has_gnu_symbols
+	      |= elf_gnu_symbol_ifunc;
+	  if ((flags & BSF_GNU_UNIQUE))
+	    elf_tdata (info->output_bfd)->has_gnu_symbols
+	      |= elf_gnu_symbol_unique;
+	}
 
       h = *sym_hash;
       /* We need to make sure that indirect symbol dynamic flags are
diff --git a/bfd/elfxx-aarch64.c b/bfd/elfxx-aarch64.c
index 45a732d..af37f82 100644
--- a/bfd/elfxx-aarch64.c
+++ b/bfd/elfxx-aarch64.c
@@ -558,25 +558,6 @@ _bfd_aarch64_elf_resolve_relocation (bfd_reloc_code_real_type r_type,
   return value;
 }
 
-/* Hook called by the linker routine which adds symbols from an object
-   file.  */
-
-bfd_boolean
-_bfd_aarch64_elf_add_symbol_hook (bfd *abfd, struct bfd_link_info *info,
-				  Elf_Internal_Sym *sym,
-				  const char **namep ATTRIBUTE_UNUSED,
-				  flagword *flagsp ATTRIBUTE_UNUSED,
-				  asection **secp ATTRIBUTE_UNUSED,
-				  bfd_vma *valp ATTRIBUTE_UNUSED)
-{
-  if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC
-      && (abfd->flags & DYNAMIC) == 0
-      && bfd_get_flavour (info->output_bfd) == bfd_target_elf_flavour)
-    elf_tdata (info->output_bfd)->has_gnu_symbols |= elf_gnu_symbol_ifunc;
-
-  return TRUE;
-}
-
 /* Support for core dump NOTE sections.  */
 
 bfd_boolean
diff --git a/bfd/elfxx-aarch64.h b/bfd/elfxx-aarch64.h
index 977faf3..301af73 100644
--- a/bfd/elfxx-aarch64.h
+++ b/bfd/elfxx-aarch64.h
@@ -48,11 +48,6 @@ _bfd_aarch64_elf_resolve_relocation (bfd_reloc_code_real_type, bfd_vma, bfd_vma,
 				     bfd_vma, bfd_boolean);
 
 extern bfd_boolean
-_bfd_aarch64_elf_add_symbol_hook (bfd *, struct bfd_link_info *,
-				  Elf_Internal_Sym *, const char **,
-				  flagword *, asection **, bfd_vma *);
-
-extern bfd_boolean
 _bfd_aarch64_elf_grok_prstatus (bfd *, Elf_Internal_Note *);
 
 extern bfd_boolean
@@ -61,7 +56,6 @@ _bfd_aarch64_elf_grok_psinfo (bfd *, Elf_Internal_Note *);
 extern char *
 _bfd_aarch64_elf_write_core_note (bfd *, char *, int *, int, ...);
 
-#define elf_backend_add_symbol_hook	_bfd_aarch64_elf_add_symbol_hook
 #define elf_backend_grok_prstatus	_bfd_aarch64_elf_grok_prstatus
 #define elf_backend_grok_psinfo		_bfd_aarch64_elf_grok_psinfo
 #define elf_backend_write_core_note	_bfd_aarch64_elf_write_core_note