Set SEC_KEEP on section XXX for undefined __start_XXX/__stop_XXX

[deliverable/binutils-gdb.git] / bfd / elflink.c

diff --git a/bfd/elflink.c b/bfd/elflink.c
index c42c6e135bde963d5b332533d13c5b2298a2fc43..f9f804de739dcf0ffefbd18cac767f036bc50222 100644 (file)
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -1,6 +1,6 @@
 /* ELF linking support for BFD.
    Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
 /* ELF linking support for BFD.
    Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,

-   2005, 2006, 2007, 2008, 2009
+   2005, 2006, 2007, 2008, 2009, 2010

    Free Software Foundation, Inc.
 
    This file is part of BFD, the Binary File Descriptor library.
    Free Software Foundation, Inc.
 
    This file is part of BFD, the Binary File Descriptor library.


@@ -185,7 +185,7 @@ bfd_boolean
 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
 {
   flagword flags;
 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
 {
   flagword flags;

-  register asection *s;
+  asection *s;

   const struct elf_backend_data *bed;
 
   if (! is_elf_hash_table (info->hash))
   const struct elf_backend_data *bed;
 
   if (! is_elf_hash_table (info->hash))


@@ -570,8 +570,7 @@ bfd_elf_record_link_assignment (bfd *output_bfd,
 
   if (provide && hidden)
     {
 
   if (provide && hidden)
     {

-      const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
-
+      bed = get_elf_backend_data (output_bfd);

       h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
       (*bed->elf_backend_hide_symbol) (info, h, TRUE);
     }
       h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
       (*bed->elf_backend_hide_symbol) (info, h, TRUE);
     }


@@ -1184,9 +1183,8 @@ _bfd_elf_merge_symbol (bfd *abfd,
             was referenced before.  */
          if (h->ref_regular)
            {
             was referenced before.  */
          if (h->ref_regular)
            {

-             const struct elf_backend_data *bed
-               = get_elf_backend_data (abfd);

              struct elf_link_hash_entry *vh = *sym_hash;
              struct elf_link_hash_entry *vh = *sym_hash;

+

              vh->root.type = h->root.type;
              h->root.type = bfd_link_hash_indirect;
              (*bed->elf_backend_copy_indirect_symbol) (info, vh, h);
              vh->root.type = h->root.type;
              h->root.type = bfd_link_hash_indirect;
              (*bed->elf_backend_copy_indirect_symbol) (info, vh, h);


@@ -1548,7 +1546,6 @@ _bfd_elf_merge_symbol (bfd *abfd,
       /* Handle the case where we had a versioned symbol in a dynamic
         library and now find a definition in a normal object.  In this
         case, we make the versioned symbol point to the normal one.  */
       /* Handle the case where we had a versioned symbol in a dynamic
         library and now find a definition in a normal object.  In this
         case, we make the versioned symbol point to the normal one.  */

-      const struct elf_backend_data *bed = get_elf_backend_data (abfd);

       flip->root.type = h->root.type;
       flip->root.u.undef.abfd = h->root.u.undef.abfd;
       h->root.type = bfd_link_hash_indirect;
       flip->root.type = h->root.type;
       flip->root.u.undef.abfd = h->root.u.undef.abfd;
       h->root.type = bfd_link_hash_indirect;


@@ -3234,6 +3231,8 @@ elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
        case DT_RUNPATH:
        case DT_FILTER:
        case DT_AUXILIARY:
        case DT_RUNPATH:
        case DT_FILTER:
        case DT_AUXILIARY:

+       case DT_AUDIT:
+       case DT_DEPAUDIT:

          dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
          break;
        default:
          dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
          break;
        default:


@@ -3525,6 +3524,7 @@ elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
     {
       asection *s;
       const char *soname = NULL;
     {
       asection *s;
       const char *soname = NULL;

+      char *audit = NULL;

       struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
       int ret;
 
       struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
       int ret;
 


@@ -3653,6 +3653,11 @@ error_free_dyn:
                    ;
                  *pn = n;
                }
                    ;
                  *pn = n;
                }

+             if (dyn.d_tag == DT_AUDIT)
+               {
+                 unsigned int tagv = dyn.d_un.d_val;
+                 audit = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
+               }

            }
 
          free (dynbuf);
            }
 
          free (dynbuf);


@@ -3705,6 +3710,9 @@ error_free_dyn:
         particular dynamic object more than once.  */
       if (ret > 0)
        return TRUE;
         particular dynamic object more than once.  */
       if (ret > 0)
        return TRUE;

+
+      /* Save the DT_AUDIT entry for the linker emulation code. */
+      elf_dt_audit (abfd) = audit; 

     }
 
   /* If this is a dynamic object, we always link against the .dynsym
     }
 
   /* If this is a dynamic object, we always link against the .dynsym


@@ -3866,6 +3874,7 @@ error_free_dyn:
       bfd_boolean common;
       unsigned int old_alignment;
       bfd *old_bfd;
       bfd_boolean common;
       unsigned int old_alignment;
       bfd *old_bfd;

+      bfd * undef_bfd = NULL;

 
       override = FALSE;
 
 
       override = FALSE;
 


@@ -4097,6 +4106,20 @@ error_free_dyn:
              name = newname;
            }
 
              name = newname;
            }
 

+         /* If this is a definition of a previously undefined symbol
+            make a note of the bfd that contained the reference in
+            case we need to refer to it later on in error messages.  */
+         if (! bfd_is_und_section (sec))
+           {
+             h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
+
+             if (h != NULL
+                 && (h->root.type == bfd_link_hash_undefined
+                     || h->root.type == bfd_link_hash_undefweak)
+                 && h->root.u.undef.abfd)
+               undef_bfd = h->root.u.undef.abfd;
+           }
+

          if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
                                      &value, &old_alignment,
                                      sym_hash, &skip, &override,
          if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
                                      &value, &old_alignment,
                                      sym_hash, &skip, &override,


@@ -4362,7 +4385,6 @@ error_free_dyn:
          if (definition && (sec->flags & SEC_DEBUGGING) && !info->relocatable)
            {
              /* We don't want to make debug symbol dynamic.  */
          if (definition && (sec->flags & SEC_DEBUGGING) && !info->relocatable)
            {
              /* We don't want to make debug symbol dynamic.  */

-             (*bed->elf_backend_hide_symbol) (info, h, TRUE);

              dynsym = FALSE;
            }
 
              dynsym = FALSE;
            }
 


@@ -4437,9 +4459,12 @@ error_free_dyn:
              if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
                {
                  (*_bfd_error_handler)
              if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
                {
                  (*_bfd_error_handler)

-                   (_("%s: invalid DSO for symbol `%s' definition"),
+                   (_("%B: undefined reference to symbol '%s'"),
+                    undef_bfd == NULL ? info->output_bfd : undef_bfd, name);
+                 (*_bfd_error_handler)
+                   (_("note: '%s' is defined in DSO %B so try adding it to the linker command line"),

                     abfd, name);
                     abfd, name);

-                 bfd_set_error (bfd_error_bad_value);
+                 bfd_set_error (bfd_error_invalid_operation);

                  goto error_free_vers;
                }
 
                  goto error_free_vers;
                }
 


@@ -5451,6 +5476,8 @@ bfd_elf_size_dynamic_sections (bfd *output_bfd,
                               const char *soname,
                               const char *rpath,
                               const char *filter_shlib,
                               const char *soname,
                               const char *rpath,
                               const char *filter_shlib,

+                              const char *audit,
+                              const char *depaudit,

                               const char * const *auxiliary_filters,
                               struct bfd_link_info *info,
                               asection **sinterpptr,
                               const char * const *auxiliary_filters,
                               struct bfd_link_info *info,
                               asection **sinterpptr,


@@ -5603,6 +5630,28 @@ bfd_elf_size_dynamic_sections (bfd *output_bfd,
            }
        }
 
            }
        }
 

+      if (audit != NULL)
+       {
+         bfd_size_type indx;
+
+         indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, audit,
+                                     TRUE);
+         if (indx == (bfd_size_type) -1
+             || !_bfd_elf_add_dynamic_entry (info, DT_AUDIT, indx))
+           return FALSE;
+       }
+
+      if (depaudit != NULL)
+       {
+         bfd_size_type indx;
+
+         indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, depaudit,
+                                     TRUE);
+         if (indx == (bfd_size_type) -1
+             || !_bfd_elf_add_dynamic_entry (info, DT_DEPAUDIT, indx))
+           return FALSE;
+       }
+

       eif.info = info;
       eif.verdefs = verdefs;
       eif.failed = FALSE;
       eif.info = info;
       eif.verdefs = verdefs;
       eif.failed = FALSE;


@@ -8587,9 +8636,11 @@ elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
     strip = FALSE;
 
   /* If we're stripping it, and it's not a dynamic symbol, there's
     strip = FALSE;
 
   /* If we're stripping it, and it's not a dynamic symbol, there's

-     nothing else to do unless it is a forced local symbol.  */
+     nothing else to do unless it is a forced local symbol or a
+     STT_GNU_IFUNC symbol.  */

   if (strip
       && h->dynindx == -1
   if (strip
       && h->dynindx == -1

+      && h->type != STT_GNU_IFUNC

       && !h->forced_local)
     return TRUE;
 
       && !h->forced_local)
     return TRUE;
 


@@ -8597,7 +8648,11 @@ elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
   sym.st_size = h->size;
   sym.st_other = h->other;
   if (h->forced_local)
   sym.st_size = h->size;
   sym.st_other = h->other;
   if (h->forced_local)

-    sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
+    {
+      sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
+      /* Turn off visibility on local symbol.  */
+      sym.st_other &= ~ELF_ST_VISIBILITY (-1);
+    }

   else if (h->unique_global)
     sym.st_info = ELF_ST_INFO (STB_GNU_UNIQUE, h->type);
   else if (h->root.type == bfd_link_hash_undefweak
   else if (h->unique_global)
     sym.st_info = ELF_ST_INFO (STB_GNU_UNIQUE, h->type);
   else if (h->root.type == bfd_link_hash_undefweak


@@ -10053,9 +10108,9 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
   bfd_boolean emit_relocs;
   bfd *dynobj;
   struct elf_final_link_info finfo;
   bfd_boolean emit_relocs;
   bfd *dynobj;
   struct elf_final_link_info finfo;

-  register asection *o;
-  register struct bfd_link_order *p;
-  register bfd *sub;
+  asection *o;
+  struct bfd_link_order *p;
+  bfd *sub;

   bfd_size_type max_contents_size;
   bfd_size_type max_external_reloc_size;
   bfd_size_type max_internal_reloc_count;
   bfd_size_type max_contents_size;
   bfd_size_type max_external_reloc_size;
   bfd_size_type max_internal_reloc_count;


@@ -10504,9 +10559,10 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
          if (size == 0
              && (sec->flags & SEC_HAS_CONTENTS) == 0)
            {
          if (size == 0
              && (sec->flags & SEC_HAS_CONTENTS) == 0)
            {

-             struct bfd_link_order *o = sec->map_tail.link_order;
-             if (o != NULL)
-               size = o->offset + o->size;
+             struct bfd_link_order *ord = sec->map_tail.link_order;
+
+             if (ord != NULL)
+               size = ord->offset + ord->size;

            }
          end = sec->vma + size;
        }
            }
          end = sec->vma + size;
        }


@@ -10669,13 +10725,11 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
              asection *s;
              bfd_byte *dest;
 
              asection *s;
              bfd_byte *dest;
 

-             sym.st_size = e->isym.st_size;
-             sym.st_other = e->isym.st_other;
-
-             /* Copy the internal symbol as is.
+             /* Copy the internal symbol and turn off visibility.

                 Note that we saved a word of storage and overwrote
                 the original st_name with the dynstr_index.  */
              sym = e->isym;
                 Note that we saved a word of storage and overwrote
                 the original st_name with the dynstr_index.  */
              sym = e->isym;

+             sym.st_other &= ~ELF_ST_VISIBILITY (-1);

 
              s = bfd_section_from_elf_index (e->input_bfd,
                                              e->isym.st_shndx);
 
              s = bfd_section_from_elf_index (e->input_bfd,
                                              e->isym.st_shndx);


@@ -11277,6 +11331,8 @@ _bfd_elf_gc_mark_hook (asection *sec,
                       struct elf_link_hash_entry *h,
                       Elf_Internal_Sym *sym)
 {
                       struct elf_link_hash_entry *h,
                       Elf_Internal_Sym *sym)
 {

+  const char *sec_name;
+

   if (h != NULL)
     {
       switch (h->root.type)
   if (h != NULL)
     {
       switch (h->root.type)


@@ -11288,6 +11344,33 @@ _bfd_elf_gc_mark_hook (asection *sec,
        case bfd_link_hash_common:
          return h->root.u.c.p->section;
 
        case bfd_link_hash_common:
          return h->root.u.c.p->section;
 

+       case bfd_link_hash_undefined:
+       case bfd_link_hash_undefweak:
+         /* To work around a glibc bug, keep all XXX input sections
+            when there is an as yet undefined reference to __start_XXX
+            or __stop_XXX symbols.  The linker will later define such
+            symbols for orphan input sections that have a name
+            representable as a C identifier.  */
+         if (strncmp (h->root.root.string, "__start_", 8) == 0)
+           sec_name = h->root.root.string + 8;
+         else if (strncmp (h->root.root.string, "__stop_", 7) == 0)
+           sec_name = h->root.root.string + 7;
+         else
+           sec_name = NULL;
+
+         if (sec_name && *sec_name != '\0')
+           {
+             bfd *i;
+             
+             for (i = info->input_bfds; i; i = i->link_next)
+               {
+                 sec = bfd_get_section_by_name (i, sec_name);
+                 if (sec)
+                   sec->flags |= SEC_KEEP;
+               }
+           }
+         break;
+

        default:
          break;
        }
        default:
          break;
        }


@@ -11473,9 +11556,10 @@ elf_gc_sweep (bfd *abfd, struct bfd_link_info *info)
              o->gc_mark = first->gc_mark;
            }
          else if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
              o->gc_mark = first->gc_mark;
            }
          else if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0

-                  || (o->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) == 0)
+                  || (o->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) == 0
+                  || elf_section_data (o)->this_hdr.sh_type == SHT_NOTE)

            {
            {

-             /* Keep debug and special sections.  */
+             /* Keep debug, special and SHT_NOTE sections.  */

              o->gc_mark = 1;
            }
 
              o->gc_mark = 1;
            }
 


@@ -12495,7 +12579,7 @@ _bfd_elf_get_dynamic_reloc_section (bfd *       abfd,
    section does not exist it is created and attached to the DYNOBJ
    bfd and stored in the SRELOC field of SEC's elf_section_data
    structure.
    section does not exist it is created and attached to the DYNOBJ
    bfd and stored in the SRELOC field of SEC's elf_section_data
    structure.

-   
+

    ALIGNMENT is the alignment for the newly created section and
    IS_RELA defines whether the name should be .rela.<SEC's name>
    or .rel.<SEC's name>.  The section name is looked up in the
    ALIGNMENT is the alignment for the newly created section and
    IS_RELA defines whether the name should be .rela.<SEC's name>
    or .rel.<SEC's name>.  The section name is looked up in the


@@ -12540,3 +12624,15 @@ _bfd_elf_make_dynamic_reloc_section (asection *         sec,
 
   return reloc_sec;
 }
 
   return reloc_sec;
 }

+
+/* Copy the ELF symbol type associated with a linker hash entry.  */
+void
+_bfd_elf_copy_link_hash_symbol_type (bfd *abfd ATTRIBUTE_UNUSED,
+    struct bfd_link_hash_entry * hdest,
+    struct bfd_link_hash_entry * hsrc)
+{
+  struct elf_link_hash_entry *ehdest = (struct elf_link_hash_entry *)hdest;
+  struct elf_link_hash_entry *ehsrc = (struct elf_link_hash_entry *)hsrc;
+
+  ehdest->type = ehsrc->type;
+}