diff options
| -rw-r--r-- | bfd/ChangeLog | 11 | ||||
| -rw-r--r-- | bfd/elflink.h | 110 |
2 files changed, 120 insertions, 1 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog index e351bfb..fe91368 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,5 +1,16 @@ 1999-12-10 Nick Clifton <nickc@cygnus.com> + * elflink.h (elf_link_is_defined_archive_symbol): New + function: Decide if a symbol, in an archive map is there + because it is defined in the archive element, or because it is + just another common declaration of it. + (elf_link_add_archive_symbols): Use + elf_link_is_defined_archive_symbol to decide if an archive + element contain a reference to a common symbol should be + linked in or not. + +1999-12-10 Nick Clifton <nickc@cygnus.com> + * elflink.h: Revert previous patch. * targets.c: Revert previous patch. * libbfd-in2.h: Revert previous patch. diff --git a/bfd/elflink.h b/bfd/elflink.h index ab679a7..6e21a1f 100644 --- a/bfd/elflink.h +++ b/bfd/elflink.h @@ -80,6 +80,97 @@ elf_bfd_link_add_symbols (abfd, info) } } +/* Search the symbol table of the archive element of the archive ABFD + whoes archove map contains a mention of SYMDEF, and determine if + the symbol is defined in this element. */ +static boolean +elf_link_is_defined_archive_symbol (abfd, symdef) + bfd * abfd; + carsym * symdef; +{ + Elf_Internal_Shdr * hdr; + Elf_External_Sym * esym; + Elf_External_Sym * esymend; + Elf_External_Sym * buf = NULL; + size_t symcount; + size_t extsymcount; + size_t extsymoff; + boolean result = false; + + abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset); + if (abfd == (bfd *) NULL) + return false; + + if (! bfd_check_format (abfd, bfd_object)) + return false; + + /* Select the appropriate symbol table. */ + if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0) + hdr = &elf_tdata (abfd)->symtab_hdr; + else + hdr = &elf_tdata (abfd)->dynsymtab_hdr; + + symcount = hdr->sh_size / sizeof (Elf_External_Sym); + + /* The sh_info field of the symtab header tells us where the + external symbols start. We don't care about the local symbols. */ + if (elf_bad_symtab (abfd)) + { + extsymcount = symcount; + extsymoff = 0; + } + else + { + extsymcount = symcount - hdr->sh_info; + extsymoff = hdr->sh_info; + } + + buf = ((Elf_External_Sym *) + bfd_malloc (extsymcount * sizeof (Elf_External_Sym))); + if (buf == NULL && extsymcount != 0) + return false; + + /* Read in the symbol table. + FIXME: This ought to be cached somewhere. */ + if (bfd_seek (abfd, + hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym), + SEEK_SET) != 0 + || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd) + != extsymcount * sizeof (Elf_External_Sym))) + { + free (buf); + return false; + } + + /* Scan the symbol table looking for SYMDEF. */ + esymend = buf + extsymcount; + for (esym = buf; + esym < esymend; + esym++) + { + Elf_Internal_Sym sym; + const char * name; + + elf_swap_symbol_in (abfd, esym, & sym); + + name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name); + if (name == (const char *) NULL) + break; + + if (strcmp (name, symdef->name) == 0) + { + result = + (ELF_ST_BIND (sym.st_info) == STB_GLOBAL) + && (sym.st_shndx != SHN_UNDEF); + break; + } + } + + free (buf); + + return result; +} + /* Add symbols from an ELF archive file to the linker hash table. We don't use _bfd_generic_link_add_archive_symbols because of a @@ -200,7 +291,24 @@ elf_link_add_archive_symbols (abfd, info) if (h == NULL) continue; - if (h->root.type != bfd_link_hash_undefined) + if (h->root.type == bfd_link_hash_common) + { + /* We currently have a common symbol. The archive map contains + a reference to this symbol, so we may want to include it. We + only want to include it however, if this archive element + contains a definition of the symbol, not just another common + declaration of it. + + Unfortunately some archivers (including GNU ar) will put + declarations of common symbols into their archive maps, as + well as real definitions, so we cannot just go by the archive + map alone. Instead we must read in the element's symbol + table and check that to see what kind of symbol definition + this is. */ + if (! elf_link_is_defined_archive_symbol (abfd, symdef)) + continue; + } + else if (h->root.type != bfd_link_hash_undefined) { if (h->root.type != bfd_link_hash_undefweak) defined[i] = true; |