/* ELF linker support. Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. This file is part of BFD, the Binary File Descriptor library. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* ELF linker code. */ static bfd_boolean is_global_data_symbol_definition PARAMS ((bfd *, Elf_Internal_Sym *)); static bfd_boolean elf_link_is_defined_archive_symbol PARAMS ((bfd *, carsym *)); static bfd_boolean elf_link_add_object_symbols PARAMS ((bfd *, struct bfd_link_info *)); static bfd_boolean elf_link_add_archive_symbols PARAMS ((bfd *, struct bfd_link_info *)); static bfd_boolean elf_finalize_dynstr PARAMS ((bfd *, struct bfd_link_info *)); static bfd_boolean elf_collect_hash_codes PARAMS ((struct elf_link_hash_entry *, PTR)); static size_t compute_bucket_count PARAMS ((struct bfd_link_info *)); static void elf_link_adjust_relocs PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int, struct elf_link_hash_entry **)); static int elf_link_sort_cmp1 PARAMS ((const void *, const void *)); static int elf_link_sort_cmp2 PARAMS ((const void *, const void *)); static size_t elf_link_sort_relocs PARAMS ((bfd *, struct bfd_link_info *, asection **)); static bfd_boolean elf_section_ignore_discarded_relocs PARAMS ((asection *)); /* Given an ELF BFD, add symbols to the global hash table as appropriate. */ bfd_boolean elf_bfd_link_add_symbols (abfd, info) bfd *abfd; struct bfd_link_info *info; { switch (bfd_get_format (abfd)) { case bfd_object: return elf_link_add_object_symbols (abfd, info); case bfd_archive: return elf_link_add_archive_symbols (abfd, info); default: bfd_set_error (bfd_error_wrong_format); return FALSE; } } /* Return TRUE iff this is a non-common, definition of a non-function symbol. */ static bfd_boolean is_global_data_symbol_definition (abfd, sym) bfd * abfd ATTRIBUTE_UNUSED; Elf_Internal_Sym * sym; { /* Local symbols do not count, but target specific ones might. */ if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL && ELF_ST_BIND (sym->st_info) < STB_LOOS) return FALSE; /* Function symbols do not count. */ if (ELF_ST_TYPE (sym->st_info) == STT_FUNC) return FALSE; /* If the section is undefined, then so is the symbol. */ if (sym->st_shndx == SHN_UNDEF) return FALSE; /* If the symbol is defined in the common section, then it is a common definition and so does not count. */ if (sym->st_shndx == SHN_COMMON) return FALSE; /* If the symbol is in a target specific section then we must rely upon the backend to tell us what it is. */ if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS) /* FIXME - this function is not coded yet: return _bfd_is_global_symbol_definition (abfd, sym); Instead for now assume that the definition is not global, Even if this is wrong, at least the linker will behave in the same way that it used to do. */ return FALSE; return TRUE; } /* Search the symbol table of the archive element of the archive ABFD whose archive map contains a mention of SYMDEF, and determine if the symbol is defined in this element. */ static bfd_boolean elf_link_is_defined_archive_symbol (abfd, symdef) bfd * abfd; carsym * symdef; { Elf_Internal_Shdr * hdr; bfd_size_type symcount; bfd_size_type extsymcount; bfd_size_type extsymoff; Elf_Internal_Sym *isymbuf; Elf_Internal_Sym *isym; Elf_Internal_Sym *isymend; bfd_boolean result; 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; /* If we have already included the element containing this symbol in the link then we do not need to include it again. Just claim that any symbol it contains is not a definition, so that our caller will not decide to (re)include this element. */ if (abfd->archive_pass) 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; } if (extsymcount == 0) return FALSE; /* Read in the symbol table. */ isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff, NULL, NULL, NULL); if (isymbuf == NULL) return FALSE; /* Scan the symbol table looking for SYMDEF. */ result = FALSE; for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++) { const char *name; name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, isym->st_name); if (name == (const char *) NULL) break; if (strcmp (name, symdef->name) == 0) { result = is_global_data_symbol_definition (abfd, isym); break; } } free (isymbuf); 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 problem which arises on UnixWare. The UnixWare libc.so is an archive which includes an entry libc.so.1 which defines a bunch of symbols. The libc.so archive also includes a number of other object files, which also define symbols, some of which are the same as those defined in libc.so.1. Correct linking requires that we consider each object file in turn, and include it if it defines any symbols we need. _bfd_generic_link_add_archive_symbols does not do this; it looks through the list of undefined symbols, and includes any object file which defines them. When this algorithm is used on UnixWare, it winds up pulling in libc.so.1 early and defining a bunch of symbols. This means that some of the other objects in the archive are not included in the link, which is incorrect since they precede libc.so.1 in the archive. Fortunately, ELF archive handling is simpler than that done by _bfd_generic_link_add_archive_symbols, which has to allow for a.out oddities. In ELF, if we find a symbol in the archive map, and the symbol is currently undefined, we know that we must pull in that object file. Unfortunately, we do have to make multiple passes over the symbol table until nothing further is resolved. */ static bfd_boolean elf_link_add_archive_symbols (abfd, info) bfd *abfd; struct bfd_link_info *info; { symindex c; bfd_boolean *defined = NULL; bfd_boolean *included = NULL; carsym *symdefs; bfd_boolean loop; bfd_size_type amt; if (! bfd_has_map (abfd)) { /* An empty archive is a special case. */ if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL) return TRUE; bfd_set_error (bfd_error_no_armap); return FALSE; } /* Keep track of all symbols we know to be already defined, and all files we know to be already included. This is to speed up the second and subsequent passes. */ c = bfd_ardata (abfd)->symdef_count; if (c == 0) return TRUE; amt = c; amt *= sizeof (bfd_boolean); defined = (bfd_boolean *) bfd_zmalloc (amt); included = (bfd_boolean *) bfd_zmalloc (amt); if (defined == (bfd_boolean *) NULL || included == (bfd_boolean *) NULL) goto error_return; symdefs = bfd_ardata (abfd)->symdefs; do { file_ptr last; symindex i; carsym *symdef; carsym *symdefend; loop = FALSE; last = -1; symdef = symdefs; symdefend = symdef + c; for (i = 0; symdef < symdefend; symdef++, i++) { struct elf_link_hash_entry *h; bfd *element; struct bfd_link_hash_entry *undefs_tail; symindex mark; if (defined[i] || included[i]) continue; if (symdef->file_offset == last) { included[i] = TRUE; continue; } h = elf_link_hash_lookup (elf_hash_table (info), symdef->name, FALSE, FALSE, FALSE); if (h == NULL) { char *p, *copy; size_t len, first; /* If this is a default version (the name contains @@), look up the symbol again with only one `@' as well as without the version. The effect is that references to the symbol with and without the version will be matched by the default symbol in the archive. */ p = strchr (symdef->name, ELF_VER_CHR); if (p == NULL || p[1] != ELF_VER_CHR) continue; /* First check with only one `@'. */ len = strlen (symdef->name); copy = bfd_alloc (abfd, (bfd_size_type) len); if (copy == NULL) goto error_return; first = p - symdef->name + 1; memcpy (copy, symdef->name, first); memcpy (copy + first, symdef->name + first + 1, len - first); h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE); if (h == NULL) { /* We also need to check references to the symbol without the version. */ copy[first - 1] = '\0'; h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE); } bfd_release (abfd, copy); } if (h == NULL) continue; 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; continue; } /* We need to include this archive member. */ element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset); if (element == (bfd *) NULL) goto error_return; if (! bfd_check_format (element, bfd_object)) goto error_return; /* Doublecheck that we have not included this object already--it should be impossible, but there may be something wrong with the archive. */ if (element->archive_pass != 0) { bfd_set_error (bfd_error_bad_value); goto error_return; } element->archive_pass = 1; undefs_tail = info->hash->undefs_tail; if (! (*info->callbacks->add_archive_element) (info, element, symdef->name)) goto error_return; if (! elf_link_add_object_symbols (element, info)) goto error_return; /* If there are any new undefined symbols, we need to make another pass through the archive in order to see whether they can be defined. FIXME: This isn't perfect, because common symbols wind up on undefs_tail and because an undefined symbol which is defined later on in this pass does not require another pass. This isn't a bug, but it does make the code less efficient than it could be. */ if (undefs_tail != info->hash->undefs_tail) loop = TRUE; /* Look backward to mark all symbols from this object file which we have already seen in this pass. */ mark = i; do { included[mark] = TRUE; if (mark == 0) break; --mark; } while (symdefs[mark].file_offset == symdef->file_offset); /* We mark subsequent symbols from this object file as we go on through the loop. */ last = symdef->file_offset; } } while (loop); free (defined); free (included); return TRUE; error_return: if (defined != (bfd_boolean *) NULL) free (defined); if (included != (bfd_boolean *) NULL) free (included); return FALSE; } /* Add symbols from an ELF object file to the linker hash table. */ static bfd_boolean elf_link_add_object_symbols (abfd, info) bfd *abfd; struct bfd_link_info *info; { bfd_boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *, const Elf_Internal_Sym *, const char **, flagword *, asection **, bfd_vma *)); bfd_boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *)); bfd_boolean collect; Elf_Internal_Shdr *hdr; bfd_size_type symcount; bfd_size_type extsymcount; bfd_size_type extsymoff; struct elf_link_hash_entry **sym_hash; bfd_boolean dynamic; Elf_External_Versym *extversym = NULL; Elf_External_Versym *ever; struct elf_link_hash_entry *weaks; struct elf_link_hash_entry **nondeflt_vers = NULL; bfd_size_type nondeflt_vers_cnt = 0; Elf_Internal_Sym *isymbuf = NULL; Elf_Internal_Sym *isym; Elf_Internal_Sym *isymend; struct elf_backend_data *bed; bfd_boolean dt_needed; struct elf_link_hash_table * hash_table; bfd_size_type amt; hash_table = elf_hash_table (info); bed = get_elf_backend_data (abfd); add_symbol_hook = bed->elf_add_symbol_hook; collect = bed->collect; if ((abfd->flags & DYNAMIC) == 0) dynamic = FALSE; else { dynamic = TRUE; /* You can't use -r against a dynamic object. Also, there's no hope of using a dynamic object which does not exactly match the format of the output file. */ if (info->relocateable || info->hash->creator != abfd->xvec) { bfd_set_error (bfd_error_invalid_operation); goto error_return; } } /* As a GNU extension, any input sections which are named .gnu.warning.SYMBOL are treated as warning symbols for the given symbol. This differs from .gnu.warning sections, which generate warnings when they are included in an output file. */ if (info->executable) { asection *s; for (s = abfd->sections; s != NULL; s = s->next) { const char *name; name = bfd_get_section_name (abfd, s); if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0) { char *msg; bfd_size_type sz; name += sizeof ".gnu.warning." - 1; /* If this is a shared object, then look up the symbol in the hash table. If it is there, and it is already been defined, then we will not be using the entry from this shared object, so we don't need to warn. FIXME: If we see the definition in a regular object later on, we will warn, but we shouldn't. The only fix is to keep track of what warnings we are supposed to emit, and then handle them all at the end of the link. */ if (dynamic && abfd->xvec == info->hash->creator) { struct elf_link_hash_entry *h; h = elf_link_hash_lookup (hash_table, name, FALSE, FALSE, TRUE); /* FIXME: What about bfd_link_hash_common? */ if (h != NULL && (h->root.type == bfd_link_hash_defined || h->root.type == bfd_link_hash_defweak)) { /* We don't want to issue this warning. Clobber the section size so that the warning does not get copied into the output file. */ s->_raw_size = 0; continue; } } sz = bfd_section_size (abfd, s); msg = (char *) bfd_alloc (abfd, sz + 1); if (msg == NULL) goto error_return; if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz)) goto error_return; msg[sz] = '\0'; if (! (_bfd_generic_link_add_one_symbol (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg, FALSE, collect, (struct bfd_link_hash_entry **) NULL))) goto error_return; if (! info->relocateable) { /* Clobber the section size so that the warning does not get copied into the output file. */ s->_raw_size = 0; } } } } dt_needed = FALSE; if (! dynamic) { /* If we are creating a shared library, create all the dynamic sections immediately. We need to attach them to something, so we attach them to this BFD, provided it is the right format. FIXME: If there are no input BFD's of the same format as the output, we can't make a shared library. */ if (info->shared && is_elf_hash_table (info) && ! hash_table->dynamic_sections_created && abfd->xvec == info->hash->creator) { if (! _bfd_elf_link_create_dynamic_sections (abfd, info)) goto error_return; } } else if (! is_elf_hash_table (info)) goto error_return; else { asection *s; bfd_boolean add_needed; const char *name; bfd_size_type oldsize; bfd_size_type strindex; struct bfd_link_needed_list *rpath = NULL, *runpath = NULL; /* ld --just-symbols and dynamic objects don't mix very well. Test for --just-symbols by looking at info set up by _bfd_elf_link_just_syms. */ if ((s = abfd->sections) != NULL && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS) goto error_return; /* Find the name to use in a DT_NEEDED entry that refers to this object. If the object has a DT_SONAME entry, we use it. Otherwise, if the generic linker stuck something in elf_dt_name, we use that. Otherwise, we just use the file name. If the generic linker put a null string into elf_dt_name, we don't make a DT_NEEDED entry at all, even if there is a DT_SONAME entry. */ add_needed = TRUE; name = bfd_get_filename (abfd); if (elf_dt_name (abfd) != NULL) { name = elf_dt_name (abfd); if (*name == '\0') { if (elf_dt_soname (abfd) != NULL) dt_needed = TRUE; add_needed = FALSE; } } s = bfd_get_section_by_name (abfd, ".dynamic"); if (s != NULL) { Elf_External_Dyn *dynbuf = NULL; Elf_External_Dyn *extdyn; Elf_External_Dyn *extdynend; int elfsec; unsigned long shlink; dynbuf = (Elf_External_Dyn *) bfd_malloc (s->_raw_size); if (dynbuf == NULL) goto error_return; if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf, (file_ptr) 0, s->_raw_size)) goto error_free_dyn; elfsec = _bfd_elf_section_from_bfd_section (abfd, s); if (elfsec == -1) goto error_free_dyn; shlink = elf_elfsections (abfd)[elfsec]->sh_link; extdyn = dynbuf; extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn); for (; extdyn < extdynend; extdyn++) { Elf_Internal_Dyn dyn; elf_swap_dyn_in (abfd, extdyn, &dyn); if (dyn.d_tag == DT_SONAME) { unsigned int tagv = dyn.d_un.d_val; name = bfd_elf_string_from_elf_section (abfd, shlink, tagv); if (name == NULL) goto error_free_dyn; } if (dyn.d_tag == DT_NEEDED) { struct bfd_link_needed_list *n, **pn; char *fnm, *anm; unsigned int tagv = dyn.d_un.d_val; amt = sizeof (struct bfd_link_needed_list); n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt); fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv); if (n == NULL || fnm == NULL) goto error_free_dyn; amt = strlen (fnm) + 1; anm = bfd_alloc (abfd, amt); if (anm == NULL) goto error_free_dyn; memcpy (anm, fnm, (size_t) amt); n->name = anm; n->by = abfd; n->next = NULL; for (pn = & hash_table->needed; *pn != NULL; pn = &(*pn)->next) ; *pn = n; } if (dyn.d_tag == DT_RUNPATH) { struct bfd_link_needed_list *n, **pn; char *fnm, *anm; unsigned int tagv = dyn.d_un.d_val; amt = sizeof (struct bfd_link_needed_list); n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt); fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv); if (n == NULL || fnm == NULL) goto error_free_dyn; amt = strlen (fnm) + 1; anm = bfd_alloc (abfd, amt); if (anm == NULL) goto error_free_dyn; memcpy (anm, fnm, (size_t) amt); n->name = anm; n->by = abfd; n->next = NULL; for (pn = & runpath; *pn != NULL; pn = &(*pn)->next) ; *pn = n; } /* Ignore DT_RPATH if we have seen DT_RUNPATH. */ if (!runpath && dyn.d_tag == DT_RPATH) { struct bfd_link_needed_list *n, **pn; char *fnm, *anm; unsigned int tagv = dyn.d_un.d_val; amt = sizeof (struct bfd_link_needed_list); n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt); fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv); if (n == NULL || fnm == NULL) goto error_free_dyn; amt = strlen (fnm) + 1; anm = bfd_alloc (abfd, amt); if (anm == NULL) { error_free_dyn: free (dynbuf); goto error_return; } memcpy (anm, fnm, (size_t) amt); n->name = anm; n->by = abfd; n->next = NULL; for (pn = & rpath; *pn != NULL; pn = &(*pn)->next) ; *pn = n; } } free (dynbuf); } /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that frees all more recently bfd_alloc'd blocks as well. */ if (runpath) rpath = runpath; if (rpath) { struct bfd_link_needed_list **pn; for (pn = & hash_table->runpath; *pn != NULL; pn = &(*pn)->next) ; *pn = rpath; } /* We do not want to include any of the sections in a dynamic object in the output file. We hack by simply clobbering the list of sections in the BFD. This could be handled more cleanly by, say, a new section flag; the existing SEC_NEVER_LOAD flag is not the one we want, because that one still implies that the section takes up space in the output file. */ bfd_section_list_clear (abfd); /* If this is the first dynamic object found in the link, create the special sections required for dynamic linking. */ if (! hash_table->dynamic_sections_created) if (! _bfd_elf_link_create_dynamic_sections (abfd, info)) goto error_return; if (add_needed) { /* Add a DT_NEEDED entry for this dynamic object. */ oldsize = _bfd_elf_strtab_size (hash_table->dynstr); strindex = _bfd_elf_strtab_add (hash_table->dynstr, name, FALSE); if (strindex == (bfd_size_type) -1) goto error_return; if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr)) { asection *sdyn; Elf_External_Dyn *dyncon, *dynconend; /* The hash table size did not change, which means that the dynamic object name was already entered. If we have already included this dynamic object in the link, just ignore it. There is no reason to include a particular dynamic object more than once. */ sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic"); BFD_ASSERT (sdyn != NULL); dyncon = (Elf_External_Dyn *) sdyn->contents; dynconend = (Elf_External_Dyn *) (sdyn->contents + sdyn->_raw_size); for (; dyncon < dynconend; dyncon++) { Elf_Internal_Dyn dyn; elf_swap_dyn_in (hash_table->dynobj, dyncon, & dyn); if (dyn.d_tag == DT_NEEDED && dyn.d_un.d_val == strindex) { _bfd_elf_strtab_delref (hash_table->dynstr, strindex); return TRUE; } } } if (! elf_add_dynamic_entry (info, (bfd_vma) DT_NEEDED, strindex)) goto error_return; } /* Save the SONAME, if there is one, because sometimes the linker emulation code will need to know it. */ if (*name == '\0') name = basename (bfd_get_filename (abfd)); elf_dt_name (abfd) = name; } /* If this is a dynamic object, we always link against the .dynsym symbol table, not the .symtab symbol table. The dynamic linker will only see the .dynsym symbol table, so there is no reason to look at .symtab for a dynamic object. */ if (! dynamic || 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 at this point. */ if (elf_bad_symtab (abfd)) { extsymcount = symcount; extsymoff = 0; } else { extsymcount = symcount - hdr->sh_info; extsymoff = hdr->sh_info; } sym_hash = NULL; if (extsymcount != 0) { isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff, NULL, NULL, NULL); if (isymbuf == NULL) goto error_return; /* We store a pointer to the hash table entry for each external symbol. */ amt = extsymcount * sizeof (struct elf_link_hash_entry *); sym_hash = (struct elf_link_hash_entry **) bfd_alloc (abfd, amt); if (sym_hash == NULL) goto error_free_sym; elf_sym_hashes (abfd) = sym_hash; } if (dynamic) { /* Read in any version definitions. */ if (! _bfd_elf_slurp_version_tables (abfd)) goto error_free_sym; /* Read in the symbol versions, but don't bother to convert them to internal format. */ if (elf_dynversym (abfd) != 0) { Elf_Internal_Shdr *versymhdr; versymhdr = &elf_tdata (abfd)->dynversym_hdr; extversym = (Elf_External_Versym *) bfd_malloc (versymhdr->sh_size); if (extversym == NULL) goto error_free_sym; amt = versymhdr->sh_size; if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0 || bfd_bread ((PTR) extversym, amt, abfd) != amt) goto error_free_vers; } } weaks = NULL; ever = extversym != NULL ? extversym + extsymoff : NULL; for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL)) { int bind; bfd_vma value; asection *sec; flagword flags; const char *name; struct elf_link_hash_entry *h; bfd_boolean definition; bfd_boolean size_change_ok; bfd_boolean type_change_ok; bfd_boolean new_weakdef; bfd_boolean override; unsigned int old_alignment; bfd *old_bfd; override = FALSE; flags = BSF_NO_FLAGS; sec = NULL; value = isym->st_value; *sym_hash = NULL; bind = ELF_ST_BIND (isym->st_info); if (bind == STB_LOCAL) { /* This should be impossible, since ELF requires that all global symbols follow all local symbols, and that sh_info point to the first global symbol. Unfortunatealy, Irix 5 screws this up. */ continue; } else if (bind == STB_GLOBAL) { if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON) flags = BSF_GLOBAL; } else if (bind == STB_WEAK) flags = BSF_WEAK; else { /* Leave it up to the processor backend. */ } if (isym->st_shndx == SHN_UNDEF) sec = bfd_und_section_ptr; else if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE) { sec = section_from_elf_index (abfd, isym->st_shndx); if (sec == NULL) sec = bfd_abs_section_ptr; else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0) value -= sec->vma; } else if (isym->st_shndx == SHN_ABS) sec = bfd_abs_section_ptr; else if (isym->st_shndx == SHN_COMMON) { sec = bfd_com_section_ptr; /* What ELF calls the size we call the value. What ELF calls the value we call the alignment. */ value = isym->st_size; } else { /* Leave it up to the processor backend. */ } name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, isym->st_name); if (name == (const char *) NULL) goto error_free_vers; if (isym->st_shndx == SHN_COMMON && ELF_ST_TYPE (isym->st_info) == STT_TLS) { asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon"); if (tcomm == NULL) { tcomm = bfd_make_section (abfd, ".tcommon"); if (tcomm == NULL || !bfd_set_section_flags (abfd, tcomm, (SEC_ALLOC | SEC_IS_COMMON | SEC_LINKER_CREATED | SEC_THREAD_LOCAL))) goto error_free_vers; } sec = tcomm; } else if (add_symbol_hook) { if (! (*add_symbol_hook) (abfd, info, isym, &name, &flags, &sec, &value)) goto error_free_vers; /* The hook function sets the name to NULL if this symbol should be skipped for some reason. */ if (name == (const char *) NULL) continue; } /* Sanity check that all possibilities were handled. */ if (sec == (asection *) NULL) { bfd_set_error (bfd_error_bad_value); goto error_free_vers; } if (bfd_is_und_section (sec) || bfd_is_com_section (sec)) definition = FALSE; else definition = TRUE; size_change_ok = FALSE; type_change_ok = get_elf_backend_data (abfd)->type_change_ok; old_alignment = 0; old_bfd = NULL; if (info->hash->creator->flavour == bfd_target_elf_flavour) { Elf_Internal_Versym iver; unsigned int vernum = 0; bfd_boolean skip; if (ever != NULL) { _bfd_elf_swap_versym_in (abfd, ever, &iver); vernum = iver.vs_vers & VERSYM_VERSION; /* If this is a hidden symbol, or if it is not version 1, we append the version name to the symbol name. However, we do not modify a non-hidden absolute symbol, because it might be the version symbol itself. FIXME: What if it isn't? */ if ((iver.vs_vers & VERSYM_HIDDEN) != 0 || (vernum > 1 && ! bfd_is_abs_section (sec))) { const char *verstr; size_t namelen, verlen, newlen; char *newname, *p; if (isym->st_shndx != SHN_UNDEF) { if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info) { (*_bfd_error_handler) (_("%s: %s: invalid version %u (max %d)"), bfd_archive_filename (abfd), name, vernum, elf_tdata (abfd)->dynverdef_hdr.sh_info); bfd_set_error (bfd_error_bad_value); goto error_free_vers; } else if (vernum > 1) verstr = elf_tdata (abfd)->verdef[vernum - 1].vd_nodename; else verstr = ""; } else { /* We cannot simply test for the number of entries in the VERNEED section since the numbers for the needed versions do not start at 0. */ Elf_Internal_Verneed *t; verstr = NULL; for (t = elf_tdata (abfd)->verref; t != NULL; t = t->vn_nextref) { Elf_Internal_Vernaux *a; for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr) { if (a->vna_other == vernum) { verstr = a->vna_nodename; break; } } if (a != NULL) break; } if (verstr == NULL) { (*_bfd_error_handler) (_("%s: %s: invalid needed version %d"), bfd_archive_filename (abfd), name, vernum); bfd_set_error (bfd_error_bad_value); goto error_free_vers; } } namelen = strlen (name); verlen = strlen (verstr); newlen = namelen + verlen + 2; if ((iver.vs_vers & VERSYM_HIDDEN) == 0 && isym->st_shndx != SHN_UNDEF) ++newlen; newname = (char *) bfd_alloc (abfd, (bfd_size_type) newlen); if (newname == NULL) goto error_free_vers; memcpy (newname, name, namelen); p = newname + namelen; *p++ = ELF_VER_CHR; /* If this is a defined non-hidden version symbol, we add another @ to the name. This indicates the default version of the symbol. */ if ((iver.vs_vers & VERSYM_HIDDEN) == 0 && isym->st_shndx != SHN_UNDEF) *p++ = ELF_VER_CHR; memcpy (p, verstr, verlen + 1); name = newname; } } if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec, &value, sym_hash, &skip, &override, &type_change_ok, &size_change_ok, dt_needed)) goto error_free_vers; if (skip) continue; if (override) definition = FALSE; h = *sym_hash; 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; /* Remember the old alignment if this is a common symbol, so that we don't reduce the alignment later on. We can't check later, because _bfd_generic_link_add_one_symbol will set a default for the alignment which we want to override. We also remember the old bfd where the existing definition comes from. */ switch (h->root.type) { default: break; case bfd_link_hash_defined: case bfd_link_hash_defweak: old_bfd = h->root.u.def.section->owner; break; case bfd_link_hash_common: old_bfd = h->root.u.c.p->section->owner; old_alignment = h->root.u.c.p->alignment_power; break; } if (elf_tdata (abfd)->verdef != NULL && ! override && vernum > 1 && definition) h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1]; } if (! (_bfd_generic_link_add_one_symbol (info, abfd, name, flags, sec, value, (const char *) NULL, FALSE, collect, (struct bfd_link_hash_entry **) sym_hash))) goto error_free_vers; h = *sym_hash; 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; *sym_hash = h; new_weakdef = FALSE; if (dynamic && definition && (flags & BSF_WEAK) != 0 && ELF_ST_TYPE (isym->st_info) != STT_FUNC && info->hash->creator->flavour == bfd_target_elf_flavour && h->weakdef == NULL) { /* Keep a list of all weak defined non function symbols from a dynamic object, using the weakdef field. Later in this function we will set the weakdef field to the correct value. We only put non-function symbols from dynamic objects on this list, because that happens to be the only time we need to know the normal symbol corresponding to a weak symbol, and the information is time consuming to figure out. If the weakdef field is not already NULL, then this symbol was already defined by some previous dynamic object, and we will be using that previous definition anyhow. */ h->weakdef = weaks; weaks = h; new_weakdef = TRUE; } /* Set the alignment of a common symbol. */ if (isym->st_shndx == SHN_COMMON && h->root.type == bfd_link_hash_common) { unsigned int align; align = bfd_log2 (isym->st_value); if (align > old_alignment /* Permit an alignment power of zero if an alignment of one is specified and no other alignments have been specified. */ || (isym->st_value == 1 && old_alignment == 0)) h->root.u.c.p->alignment_power = align; else h->root.u.c.p->alignment_power = old_alignment; } if (info->hash->creator->flavour == bfd_target_elf_flavour) { int old_flags; bfd_boolean dynsym; int new_flag; /* Check the alignment when a common symbol is involved. This can change when a common symbol is overriden by a normal definition or a common symbol is ignored due to the old normal definition. We need to make sure the maximum alignment is maintained. */ if ((old_alignment || isym->st_shndx == SHN_COMMON) && h->root.type != bfd_link_hash_common) { unsigned int common_align; unsigned int normal_align; unsigned int symbol_align; bfd *normal_bfd; bfd *common_bfd; symbol_align = ffs (h->root.u.def.value) - 1; if ((h->root.u.def.section->owner->flags & DYNAMIC) == 0) { normal_align = h->root.u.def.section->alignment_power; if (normal_align > symbol_align) normal_align = symbol_align; } else normal_align = symbol_align; if (old_alignment) { common_align = old_alignment; common_bfd = old_bfd; normal_bfd = abfd; } else { common_align = bfd_log2 (isym->st_value); common_bfd = abfd; normal_bfd = old_bfd; } if (normal_align < common_align) (*_bfd_error_handler) (_("Warning: alignment %u of symbol `%s' in %s is smaller than %u in %s"), 1 << normal_align, name, bfd_archive_filename (normal_bfd), 1 << common_align, bfd_archive_filename (common_bfd)); } /* Remember the symbol size and type. */ if (isym->st_size != 0 && (definition || h->size == 0)) { if (h->size != 0 && h->size != isym->st_size && ! size_change_ok) (*_bfd_error_handler) (_("Warning: size of symbol `%s' changed from %lu in %s to %lu in %s"), name, (unsigned long) h->size, bfd_archive_filename (old_bfd), (unsigned long) isym->st_size, bfd_archive_filename (abfd)); h->size = isym->st_size; } /* If this is a common symbol, then we always want H->SIZE to be the size of the common symbol. The code just above won't fix the size if a common symbol becomes larger. We don't warn about a size change here, because that is covered by --warn-common. */ if (h->root.type == bfd_link_hash_common) h->size = h->root.u.c.size; if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE && (definition || h->type == STT_NOTYPE)) { if (h->type != STT_NOTYPE && h->type != ELF_ST_TYPE (isym->st_info) && ! type_change_ok) (*_bfd_error_handler) (_("Warning: type of symbol `%s' changed from %d to %d in %s"), name, h->type, ELF_ST_TYPE (isym->st_info), bfd_archive_filename (abfd)); h->type = ELF_ST_TYPE (isym->st_info); } /* If st_other has a processor-specific meaning, specific code might be needed here. We never merge the visibility attribute with the one from a dynamic object. */ if (isym->st_other != 0 && !dynamic) { unsigned char hvis, symvis, other, nvis; /* Take the balance of OTHER from the definition. */ other = (definition ? isym->st_other : h->other); other &= ~ ELF_ST_VISIBILITY (-1); /* Combine visibilities, using the most constraining one. */ hvis = ELF_ST_VISIBILITY (h->other); symvis = ELF_ST_VISIBILITY (isym->st_other); if (! hvis) nvis = symvis; else if (! symvis) nvis = hvis; else nvis = hvis < symvis ? hvis : symvis; h->other = other | nvis; } /* Set a flag in the hash table entry indicating the type of reference or definition we just found. Keep a count of the number of dynamic symbols we find. A dynamic symbol is one which is referenced or defined by both a regular object and a shared object. */ old_flags = h->elf_link_hash_flags; dynsym = FALSE; if (! dynamic) { if (! definition) { new_flag = ELF_LINK_HASH_REF_REGULAR; if (bind != STB_WEAK) new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK; } else new_flag = ELF_LINK_HASH_DEF_REGULAR; if (! info->executable || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC | ELF_LINK_HASH_REF_DYNAMIC)) != 0) dynsym = TRUE; } else { if (! definition) new_flag = ELF_LINK_HASH_REF_DYNAMIC; else new_flag = ELF_LINK_HASH_DEF_DYNAMIC; if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0 || (h->weakdef != NULL && ! new_weakdef && h->weakdef->dynindx != -1)) dynsym = TRUE; } h->elf_link_hash_flags |= new_flag; /* Check to see if we need to add an indirect symbol for the default name. */ if (definition || h->root.type == bfd_link_hash_common) if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym, &sec, &value, &dynsym, override, dt_needed)) goto error_free_vers; if (definition && !dynamic) { char *p = strchr (name, ELF_VER_CHR); if (p != NULL && p[1] != ELF_VER_CHR) { /* Queue non-default versions so that .symver x, x@FOO aliases can be checked. */ if (! nondeflt_vers) { amt = (isymend - isym + 1) * sizeof (struct elf_link_hash_entry *); nondeflt_vers = bfd_malloc (amt); } nondeflt_vers [nondeflt_vers_cnt++] = h; } } if (dynsym && h->dynindx == -1) { if (! _bfd_elf_link_record_dynamic_symbol (info, h)) goto error_free_vers; if (h->weakdef != NULL && ! new_weakdef && h->weakdef->dynindx == -1) { if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef)) goto error_free_vers; } } else if (dynsym && h->dynindx != -1) /* If the symbol already has a dynamic index, but visibility says it should not be visible, turn it into a local symbol. */ switch (ELF_ST_VISIBILITY (h->other)) { case STV_INTERNAL: case STV_HIDDEN: (*bed->elf_backend_hide_symbol) (info, h, TRUE); break; } if (dt_needed && definition && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0) { bfd_size_type oldsize; bfd_size_type strindex; if (! is_elf_hash_table (info)) goto error_free_vers; /* The symbol from a DT_NEEDED object is referenced from the regular object to create a dynamic executable. We have to make sure there is a DT_NEEDED entry for it. */ dt_needed = FALSE; oldsize = _bfd_elf_strtab_size (hash_table->dynstr); strindex = _bfd_elf_strtab_add (hash_table->dynstr, elf_dt_soname (abfd), FALSE); if (strindex == (bfd_size_type) -1) goto error_free_vers; if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr)) { asection *sdyn; Elf_External_Dyn *dyncon, *dynconend; sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic"); BFD_ASSERT (sdyn != NULL); dyncon = (Elf_External_Dyn *) sdyn->contents; dynconend = (Elf_External_Dyn *) (sdyn->contents + sdyn->_raw_size); for (; dyncon < dynconend; dyncon++) { Elf_Internal_Dyn dyn; elf_swap_dyn_in (hash_table->dynobj, dyncon, &dyn); BFD_ASSERT (dyn.d_tag != DT_NEEDED || dyn.d_un.d_val != strindex); } } if (! elf_add_dynamic_entry (info, (bfd_vma) DT_NEEDED, strindex)) goto error_free_vers; } } } /* Now that all the symbols from this input file are created, handle .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */ if (nondeflt_vers != NULL) { bfd_size_type cnt, symidx; for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt) { struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi; char *shortname, *p; p = strchr (h->root.root.string, ELF_VER_CHR); if (p == NULL || (h->root.type != bfd_link_hash_defined && h->root.type != bfd_link_hash_defweak)) continue; amt = p - h->root.root.string; shortname = bfd_malloc (amt + 1); memcpy (shortname, h->root.root.string, amt); shortname[amt] = '\0'; hi = (struct elf_link_hash_entry *) bfd_link_hash_lookup (info->hash, shortname, FALSE, FALSE, FALSE); if (hi != NULL && hi->root.type == h->root.type && hi->root.u.def.value == h->root.u.def.value && hi->root.u.def.section == h->root.u.def.section) { (*bed->elf_backend_hide_symbol) (info, hi, TRUE); hi->root.type = bfd_link_hash_indirect; hi->root.u.i.link = (struct bfd_link_hash_entry *) h; (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi); sym_hash = elf_sym_hashes (abfd); if (sym_hash) for (symidx = 0; symidx < extsymcount; ++symidx) if (sym_hash[symidx] == hi) { sym_hash[symidx] = h; break; } } free (shortname); } free (nondeflt_vers); nondeflt_vers = NULL; } if (extversym != NULL) { free (extversym); extversym = NULL; } if (isymbuf != NULL) free (isymbuf); isymbuf = NULL; /* Now set the weakdefs field correctly for all the weak defined symbols we found. The only way to do this is to search all the symbols. Since we only need the information for non functions in dynamic objects, that's the only time we actually put anything on the list WEAKS. We need this information so that if a regular object refers to a symbol defined weakly in a dynamic object, the real symbol in the dynamic object is also put in the dynamic symbols; we also must arrange for both symbols to point to the same memory location. We could handle the general case of symbol aliasing, but a general symbol alias can only be generated in assembler code, handling it correctly would be very time consuming, and other ELF linkers don't handle general aliasing either. */ while (weaks != NULL) { struct elf_link_hash_entry *hlook; asection *slook; bfd_vma vlook; struct elf_link_hash_entry **hpp; struct elf_link_hash_entry **hppend; hlook = weaks; weaks = hlook->weakdef; hlook->weakdef = NULL; BFD_ASSERT (hlook->root.type == bfd_link_hash_defined || hlook->root.type == bfd_link_hash_defweak || hlook->root.type == bfd_link_hash_common || hlook->root.type == bfd_link_hash_indirect); slook = hlook->root.u.def.section; vlook = hlook->root.u.def.value; hpp = elf_sym_hashes (abfd); hppend = hpp + extsymcount; for (; hpp < hppend; hpp++) { struct elf_link_hash_entry *h; h = *hpp; if (h != NULL && h != hlook && h->root.type == bfd_link_hash_defined && h->root.u.def.section == slook && h->root.u.def.value == vlook) { hlook->weakdef = h; /* If the weak definition is in the list of dynamic symbols, make sure the real definition is put there as well. */ if (hlook->dynindx != -1 && h->dynindx == -1) { if (! _bfd_elf_link_record_dynamic_symbol (info, h)) goto error_return; } /* If the real definition is in the list of dynamic symbols, make sure the weak definition is put there as well. If we don't do this, then the dynamic loader might not merge the entries for the real definition and the weak definition. */ if (h->dynindx != -1 && hlook->dynindx == -1) { if (! _bfd_elf_link_record_dynamic_symbol (info, hlook)) goto error_return; } break; } } } /* If this object is the same format as the output object, and it is not a shared library, then let the backend look through the relocs. This is required to build global offset table entries and to arrange for dynamic relocs. It is not required for the particular common case of linking non PIC code, even when linking against shared libraries, but unfortunately there is no way of knowing whether an object file has been compiled PIC or not. Looking through the relocs is not particularly time consuming. The problem is that we must either (1) keep the relocs in memory, which causes the linker to require additional runtime memory or (2) read the relocs twice from the input file, which wastes time. This would be a good case for using mmap. I have no idea how to handle linking PIC code into a file of a different format. It probably can't be done. */ check_relocs = get_elf_backend_data (abfd)->check_relocs; if (! dynamic && abfd->xvec == info->hash->creator && check_relocs != NULL) { asection *o; for (o = abfd->sections; o != NULL; o = o->next) { Elf_Internal_Rela *internal_relocs; bfd_boolean ok; if ((o->flags & SEC_RELOC) == 0 || o->reloc_count == 0 || ((info->strip == strip_all || info->strip == strip_debugger) && (o->flags & SEC_DEBUGGING) != 0) || bfd_is_abs_section (o->output_section)) continue; internal_relocs = _bfd_elf_link_read_relocs (abfd, o, (PTR) NULL, (Elf_Internal_Rela *) NULL, info->keep_memory); if (internal_relocs == NULL) goto error_return; ok = (*check_relocs) (abfd, info, o, internal_relocs); if (elf_section_data (o)->relocs != internal_relocs) free (internal_relocs); if (! ok) goto error_return; } } /* If this is a non-traditional link, try to optimize the handling of the .stab/.stabstr sections. */ if (! dynamic && ! info->traditional_format && info->hash->creator->flavour == bfd_target_elf_flavour && is_elf_hash_table (info) && (info->strip != strip_all && info->strip != strip_debugger)) { asection *stab, *stabstr; stab = bfd_get_section_by_name (abfd, ".stab"); if (stab != NULL && (stab->flags & SEC_MERGE) == 0 && !bfd_is_abs_section (stab->output_section)) { stabstr = bfd_get_section_by_name (abfd, ".stabstr"); if (stabstr != NULL) { struct bfd_elf_section_data *secdata; secdata = elf_section_data (stab); if (! _bfd_link_section_stabs (abfd, & hash_table->stab_info, stab, stabstr, &secdata->sec_info)) goto error_return; if (secdata->sec_info) stab->sec_info_type = ELF_INFO_TYPE_STABS; } } } if (! info->relocateable && ! dynamic && is_elf_hash_table (info)) { asection *s; for (s = abfd->sections; s != NULL; s = s->next) if ((s->flags & SEC_MERGE) != 0 && !bfd_is_abs_section (s->output_section)) { struct bfd_elf_section_data *secdata; secdata = elf_section_data (s); if (! _bfd_merge_section (abfd, & hash_table->merge_info, s, &secdata->sec_info)) goto error_return; else if (secdata->sec_info) s->sec_info_type = ELF_INFO_TYPE_MERGE; } } if (is_elf_hash_table (info)) { /* Add this bfd to the loaded list. */ struct elf_link_loaded_list *n; n = ((struct elf_link_loaded_list *) bfd_alloc (abfd, sizeof (struct elf_link_loaded_list))); if (n == NULL) goto error_return; n->abfd = abfd; n->next = hash_table->loaded; hash_table->loaded = n; } return TRUE; error_free_vers: if (nondeflt_vers != NULL) free (nondeflt_vers); if (extversym != NULL) free (extversym); error_free_sym: if (isymbuf != NULL) free (isymbuf); error_return: return FALSE; } /* Add an entry to the .dynamic table. */ bfd_boolean elf_add_dynamic_entry (info, tag, val) struct bfd_link_info *info; bfd_vma tag; bfd_vma val; { Elf_Internal_Dyn dyn; bfd *dynobj; asection *s; bfd_size_type newsize; bfd_byte *newcontents; if (! is_elf_hash_table (info)) return FALSE; dynobj = elf_hash_table (info)->dynobj; s = bfd_get_section_by_name (dynobj, ".dynamic"); BFD_ASSERT (s != NULL); newsize = s->_raw_size + sizeof (Elf_External_Dyn); newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize); if (newcontents == NULL) return FALSE; dyn.d_tag = tag; dyn.d_un.d_val = val; elf_swap_dyn_out (dynobj, &dyn, (Elf_External_Dyn *) (newcontents + s->_raw_size)); s->_raw_size = newsize; s->contents = newcontents; return TRUE; } /* Array used to determine the number of hash table buckets to use based on the number of symbols there are. If there are fewer than 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets, fewer than 37 we use 17 buckets, and so forth. We never use more than 32771 buckets. */ static const size_t elf_buckets[] = { 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209, 16411, 32771, 0 }; /* Compute bucket count for hashing table. We do not use a static set of possible tables sizes anymore. Instead we determine for all possible reasonable sizes of the table the outcome (i.e., the number of collisions etc) and choose the best solution. The weighting functions are not too simple to allow the table to grow without bounds. Instead one of the weighting factors is the size. Therefore the result is always a good payoff between few collisions (= short chain lengths) and table size. */ static size_t compute_bucket_count (info) struct bfd_link_info *info; { size_t dynsymcount = elf_hash_table (info)->dynsymcount; size_t best_size = 0; unsigned long int *hashcodes; unsigned long int *hashcodesp; unsigned long int i; bfd_size_type amt; /* Compute the hash values for all exported symbols. At the same time store the values in an array so that we could use them for optimizations. */ amt = dynsymcount; amt *= sizeof (unsigned long int); hashcodes = (unsigned long int *) bfd_malloc (amt); if (hashcodes == NULL) return 0; hashcodesp = hashcodes; /* Put all hash values in HASHCODES. */ elf_link_hash_traverse (elf_hash_table (info), elf_collect_hash_codes, &hashcodesp); /* We have a problem here. The following code to optimize the table size requires an integer type with more the 32 bits. If BFD_HOST_U_64_BIT is set we know about such a type. */ #ifdef BFD_HOST_U_64_BIT if (info->optimize) { unsigned long int nsyms = hashcodesp - hashcodes; size_t minsize; size_t maxsize; BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0); unsigned long int *counts ; /* Possible optimization parameters: if we have NSYMS symbols we say that the hashing table must at least have NSYMS/4 and at most 2*NSYMS buckets. */ minsize = nsyms / 4; if (minsize == 0) minsize = 1; best_size = maxsize = nsyms * 2; /* Create array where we count the collisions in. We must use bfd_malloc since the size could be large. */ amt = maxsize; amt *= sizeof (unsigned long int); counts = (unsigned long int *) bfd_malloc (amt); if (counts == NULL) { free (hashcodes); return 0; } /* Compute the "optimal" size for the hash table. The criteria is a minimal chain length. The minor criteria is (of course) the size of the table. */ for (i = minsize; i < maxsize; ++i) { /* Walk through the array of hashcodes and count the collisions. */ BFD_HOST_U_64_BIT max; unsigned long int j; unsigned long int fact; memset (counts, '\0', i * sizeof (unsigned long int)); /* Determine how often each hash bucket is used. */ for (j = 0; j < nsyms; ++j) ++counts[hashcodes[j] % i]; /* For the weight function we need some information about the pagesize on the target. This is information need not be 100% accurate. Since this information is not available (so far) we define it here to a reasonable default value. If it is crucial to have a better value some day simply define this value. */ # ifndef BFD_TARGET_PAGESIZE # define BFD_TARGET_PAGESIZE (4096) # endif /* We in any case need 2 + NSYMS entries for the size values and the chains. */ max = (2 + nsyms) * (ARCH_SIZE / 8); # if 1 /* Variant 1: optimize for short chains. We add the squares of all the chain lengths (which favous many small chain over a few long chains). */ for (j = 0; j < i; ++j) max += counts[j] * counts[j]; /* This adds penalties for the overall size of the table. */ fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1; max *= fact * fact; # else /* Variant 2: Optimize a lot more for small table. Here we also add squares of the size but we also add penalties for empty slots (the +1 term). */ for (j = 0; j < i; ++j) max += (1 + counts[j]) * (1 + counts[j]); /* The overall size of the table is considered, but not as strong as in variant 1, where it is squared. */ fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1; max *= fact; # endif /* Compare with current best results. */ if (max < best_chlen) { best_chlen = max; best_size = i; } } free (counts); } else #endif /* defined (BFD_HOST_U_64_BIT) */ { /* This is the fallback solution if no 64bit type is available or if we are not supposed to spend much time on optimizations. We select the bucket count using a fixed set of numbers. */ for (i = 0; elf_buckets[i] != 0; i++) { best_size = elf_buckets[i]; if (dynsymcount < elf_buckets[i + 1]) break; } } /* Free the arrays we needed. */ free (hashcodes); return best_size; } /* Set up the sizes and contents of the ELF dynamic sections. This is called by the ELF linker emulation before_allocation routine. We must set the sizes of the sections before the linker sets the addresses of the various sections. */ bfd_boolean NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath, filter_shlib, auxiliary_filters, info, sinterpptr, verdefs) bfd *output_bfd; const char *soname; const char *rpath; const char *filter_shlib; const char * const *auxiliary_filters; struct bfd_link_info *info; asection **sinterpptr; struct bfd_elf_version_tree *verdefs; { bfd_size_type soname_indx; bfd *dynobj; struct elf_backend_data *bed; struct elf_assign_sym_version_info asvinfo; *sinterpptr = NULL; soname_indx = (bfd_size_type) -1; if (info->hash->creator->flavour != bfd_target_elf_flavour) return TRUE; if (! is_elf_hash_table (info)) return TRUE; if (info->execstack) elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X; else if (info->noexecstack) elf_tdata (output_bfd)->stack_flags = PF_R | PF_W; else { bfd *inputobj; asection *notesec = NULL; int exec = 0; for (inputobj = info->input_bfds; inputobj; inputobj = inputobj->link_next) { asection *s; if (inputobj->flags & DYNAMIC) continue; s = bfd_get_section_by_name (inputobj, ".note.GNU-stack"); if (s) { if (s->flags & SEC_CODE) exec = PF_X; notesec = s; } else exec = PF_X; } if (notesec) { elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec; if (exec && info->relocateable && notesec->output_section != bfd_abs_section_ptr) notesec->output_section->flags |= SEC_CODE; } } /* Any syms created from now on start with -1 in got.refcount/offset and plt.refcount/offset. */ elf_hash_table (info)->init_refcount = elf_hash_table (info)->init_offset; /* The backend may have to create some sections regardless of whether we're dynamic or not. */ bed = get_elf_backend_data (output_bfd); if (bed->elf_backend_always_size_sections && ! (*bed->elf_backend_always_size_sections) (output_bfd, info)) return FALSE; dynobj = elf_hash_table (info)->dynobj; /* If there were no dynamic objects in the link, there is nothing to do here. */ if (dynobj == NULL) return TRUE; if (! _bfd_elf_maybe_strip_eh_frame_hdr (info)) return FALSE; if (elf_hash_table (info)->dynamic_sections_created) { struct elf_info_failed eif; struct elf_link_hash_entry *h; asection *dynstr; struct bfd_elf_version_tree *t; struct bfd_elf_version_expr *d; bfd_boolean all_defined; *sinterpptr = bfd_get_section_by_name (dynobj, ".interp"); BFD_ASSERT (*sinterpptr != NULL || info->shared); if (soname != NULL) { soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, soname, TRUE); if (soname_indx == (bfd_size_type) -1 || ! elf_add_dynamic_entry (info, (bfd_vma) DT_SONAME, soname_indx)) return FALSE; } if (info->symbolic) { if (! elf_add_dynamic_entry (info, (bfd_vma) DT_SYMBOLIC, (bfd_vma) 0)) return FALSE; info->flags |= DF_SYMBOLIC; } if (rpath != NULL) { bfd_size_type indx; indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath, TRUE); if (info->new_dtags) _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx); if (indx == (bfd_size_type) -1 || ! elf_add_dynamic_entry (info, (bfd_vma) DT_RPATH, indx) || (info->new_dtags && ! elf_add_dynamic_entry (info, (bfd_vma) DT_RUNPATH, indx))) return FALSE; } if (filter_shlib != NULL) { bfd_size_type indx; indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, filter_shlib, TRUE); if (indx == (bfd_size_type) -1 || ! elf_add_dynamic_entry (info, (bfd_vma) DT_FILTER, indx)) return FALSE; } if (auxiliary_filters != NULL) { const char * const *p; for (p = auxiliary_filters; *p != NULL; p++) { bfd_size_type indx; indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, *p, TRUE); if (indx == (bfd_size_type) -1 || ! elf_add_dynamic_entry (info, (bfd_vma) DT_AUXILIARY, indx)) return FALSE; } } eif.info = info; eif.verdefs = verdefs; eif.failed = FALSE; /* If we are supposed to export all symbols into the dynamic symbol table (this is not the normal case), then do so. */ if (info->export_dynamic) { elf_link_hash_traverse (elf_hash_table (info), _bfd_elf_export_symbol, (PTR) &eif); if (eif.failed) return FALSE; } /* Make all global versions with definiton. */ for (t = verdefs; t != NULL; t = t->next) for (d = t->globals; d != NULL; d = d->next) if (!d->symver && strchr (d->pattern, '*') == NULL) { const char *verstr, *name; size_t namelen, verlen, newlen; char *newname, *p; struct elf_link_hash_entry *newh; name = d->pattern; namelen = strlen (name); verstr = t->name; verlen = strlen (verstr); newlen = namelen + verlen + 3; newname = (char *) bfd_malloc ((bfd_size_type) newlen); if (newname == NULL) return FALSE; memcpy (newname, name, namelen); /* Check the hidden versioned definition. */ p = newname + namelen; *p++ = ELF_VER_CHR; memcpy (p, verstr, verlen + 1); newh = elf_link_hash_lookup (elf_hash_table (info), newname, FALSE, FALSE, FALSE); if (newh == NULL || (newh->root.type != bfd_link_hash_defined && newh->root.type != bfd_link_hash_defweak)) { /* Check the default versioned definition. */ *p++ = ELF_VER_CHR; memcpy (p, verstr, verlen + 1); newh = elf_link_hash_lookup (elf_hash_table (info), newname, FALSE, FALSE, FALSE); } free (newname); /* Mark this version if there is a definition and it is not defined in a shared object. */ if (newh != NULL && ((newh->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0) && (newh->root.type == bfd_link_hash_defined || newh->root.type == bfd_link_hash_defweak)) d->symver = 1; } /* Attach all the symbols to their version information. */ asvinfo.output_bfd = output_bfd; asvinfo.info = info; asvinfo.verdefs = verdefs; asvinfo.failed = FALSE; elf_link_hash_traverse (elf_hash_table (info), _bfd_elf_link_assign_sym_version, (PTR) &asvinfo); if (asvinfo.failed) return FALSE; if (!info->allow_undefined_version) { /* Check if all global versions have a definiton. */ all_defined = TRUE; for (t = verdefs; t != NULL; t = t->next) for (d = t->globals; d != NULL; d = d->next) if (!d->symver && !d->script && strchr (d->pattern, '*') == NULL) { (*_bfd_error_handler) (_("%s: undefined version: %s"), d->pattern, t->name); all_defined = FALSE; } if (!all_defined) { bfd_set_error (bfd_error_bad_value); return FALSE; } } /* Find all symbols which were defined in a dynamic object and make the backend pick a reasonable value for them. */ elf_link_hash_traverse (elf_hash_table (info), _bfd_elf_adjust_dynamic_symbol, (PTR) &eif); if (eif.failed) return FALSE; /* Add some entries to the .dynamic section. We fill in some of the values later, in elf_bfd_final_link, but we must add the entries now so that we know the final size of the .dynamic section. */ /* If there are initialization and/or finalization functions to call then add the corresponding DT_INIT/DT_FINI entries. */ h = (info->init_function ? elf_link_hash_lookup (elf_hash_table (info), info->init_function, FALSE, FALSE, FALSE) : NULL); if (h != NULL && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR | ELF_LINK_HASH_DEF_REGULAR)) != 0) { if (! elf_add_dynamic_entry (info, (bfd_vma) DT_INIT, (bfd_vma) 0)) return FALSE; } h = (info->fini_function ? elf_link_hash_lookup (elf_hash_table (info), info->fini_function, FALSE, FALSE, FALSE) : NULL); if (h != NULL && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR | ELF_LINK_HASH_DEF_REGULAR)) != 0) { if (! elf_add_dynamic_entry (info, (bfd_vma) DT_FINI, (bfd_vma) 0)) return FALSE; } if (bfd_get_section_by_name (output_bfd, ".preinit_array") != NULL) { /* DT_PREINIT_ARRAY is not allowed in shared library. */ if (! info->executable) { bfd *sub; asection *o; for (sub = info->input_bfds; sub != NULL; sub = sub->link_next) for (o = sub->sections; o != NULL; o = o->next) if (elf_section_data (o)->this_hdr.sh_type == SHT_PREINIT_ARRAY) { (*_bfd_error_handler) (_("%s: .preinit_array section is not allowed in DSO"), bfd_archive_filename (sub)); break; } bfd_set_error (bfd_error_nonrepresentable_section); return FALSE; } if (!elf_add_dynamic_entry (info, (bfd_vma) DT_PREINIT_ARRAY, (bfd_vma) 0) || !elf_add_dynamic_entry (info, (bfd_vma) DT_PREINIT_ARRAYSZ, (bfd_vma) 0)) return FALSE; } if (bfd_get_section_by_name (output_bfd, ".init_array") != NULL) { if (!elf_add_dynamic_entry (info, (bfd_vma) DT_INIT_ARRAY, (bfd_vma) 0) || !elf_add_dynamic_entry (info, (bfd_vma) DT_INIT_ARRAYSZ, (bfd_vma) 0)) return FALSE; } if (bfd_get_section_by_name (output_bfd, ".fini_array") != NULL) { if (!elf_add_dynamic_entry (info, (bfd_vma) DT_FINI_ARRAY, (bfd_vma) 0) || !elf_add_dynamic_entry (info, (bfd_vma) DT_FINI_ARRAYSZ, (bfd_vma) 0)) return FALSE; } dynstr = bfd_get_section_by_name (dynobj, ".dynstr"); /* If .dynstr is excluded from the link, we don't want any of these tags. Strictly, we should be checking each section individually; This quick check covers for the case where someone does a /DISCARD/ : { *(*) }. */ if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr) { bfd_size_type strsize; strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr); if (! elf_add_dynamic_entry (info, (bfd_vma) DT_HASH, (bfd_vma) 0) || ! elf_add_dynamic_entry (info, (bfd_vma) DT_STRTAB, (bfd_vma) 0) || ! elf_add_dynamic_entry (info, (bfd_vma) DT_SYMTAB, (bfd_vma) 0) || ! elf_add_dynamic_entry (info, (bfd_vma) DT_STRSZ, strsize) || ! elf_add_dynamic_entry (info, (bfd_vma) DT_SYMENT, (bfd_vma) sizeof (Elf_External_Sym))) return FALSE; } } /* The backend must work out the sizes of all the other dynamic sections. */ if (bed->elf_backend_size_dynamic_sections && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info)) return FALSE; if (elf_hash_table (info)->dynamic_sections_created) { bfd_size_type dynsymcount; asection *s; size_t bucketcount = 0; size_t hash_entry_size; unsigned int dtagcount; /* Set up the version definition section. */ s = bfd_get_section_by_name (dynobj, ".gnu.version_d"); BFD_ASSERT (s != NULL); /* We may have created additional version definitions if we are just linking a regular application. */ verdefs = asvinfo.verdefs; /* Skip anonymous version tag. */ if (verdefs != NULL && verdefs->vernum == 0) verdefs = verdefs->next; if (verdefs == NULL) _bfd_strip_section_from_output (info, s); else { unsigned int cdefs; bfd_size_type size; struct bfd_elf_version_tree *t; bfd_byte *p; Elf_Internal_Verdef def; Elf_Internal_Verdaux defaux; cdefs = 0; size = 0; /* Make space for the base version. */ size += sizeof (Elf_External_Verdef); size += sizeof (Elf_External_Verdaux); ++cdefs; for (t = verdefs; t != NULL; t = t->next) { struct bfd_elf_version_deps *n; size += sizeof (Elf_External_Verdef); size += sizeof (Elf_External_Verdaux); ++cdefs; for (n = t->deps; n != NULL; n = n->next) size += sizeof (Elf_External_Verdaux); } s->_raw_size = size; s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size); if (s->contents == NULL && s->_raw_size != 0) return FALSE; /* Fill in the version definition section. */ p = s->contents; def.vd_version = VER_DEF_CURRENT; def.vd_flags = VER_FLG_BASE; def.vd_ndx = 1; def.vd_cnt = 1; def.vd_aux = sizeof (Elf_External_Verdef); def.vd_next = (sizeof (Elf_External_Verdef) + sizeof (Elf_External_Verdaux)); if (soname_indx != (bfd_size_type) -1) { _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, soname_indx); def.vd_hash = bfd_elf_hash (soname); defaux.vda_name = soname_indx; } else { const char *name; bfd_size_type indx; name = basename (output_bfd->filename); def.vd_hash = bfd_elf_hash (name); indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, name, FALSE); if (indx == (bfd_size_type) -1) return FALSE; defaux.vda_name = indx; } defaux.vda_next = 0; _bfd_elf_swap_verdef_out (output_bfd, &def, (Elf_External_Verdef *) p); p += sizeof (Elf_External_Verdef); _bfd_elf_swap_verdaux_out (output_bfd, &defaux, (Elf_External_Verdaux *) p); p += sizeof (Elf_External_Verdaux); for (t = verdefs; t != NULL; t = t->next) { unsigned int cdeps; struct bfd_elf_version_deps *n; struct elf_link_hash_entry *h; struct bfd_link_hash_entry *bh; cdeps = 0; for (n = t->deps; n != NULL; n = n->next) ++cdeps; /* Add a symbol representing this version. */ bh = NULL; if (! (_bfd_generic_link_add_one_symbol (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr, (bfd_vma) 0, (const char *) NULL, FALSE, get_elf_backend_data (dynobj)->collect, &bh))) return FALSE; h = (struct elf_link_hash_entry *) bh; h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF; h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR; h->type = STT_OBJECT; h->verinfo.vertree = t; if (! _bfd_elf_link_record_dynamic_symbol (info, h)) return FALSE; def.vd_version = VER_DEF_CURRENT; def.vd_flags = 0; if (t->globals == NULL && t->locals == NULL && ! t->used) def.vd_flags |= VER_FLG_WEAK; def.vd_ndx = t->vernum + 1; def.vd_cnt = cdeps + 1; def.vd_hash = bfd_elf_hash (t->name); def.vd_aux = sizeof (Elf_External_Verdef); if (t->next != NULL) def.vd_next = (sizeof (Elf_External_Verdef) + (cdeps + 1) * sizeof (Elf_External_Verdaux)); else def.vd_next = 0; _bfd_elf_swap_verdef_out (output_bfd, &def, (Elf_External_Verdef *) p); p += sizeof (Elf_External_Verdef); defaux.vda_name = h->dynstr_index; _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, h->dynstr_index); if (t->deps == NULL) defaux.vda_next = 0; else defaux.vda_next = sizeof (Elf_External_Verdaux); t->name_indx = defaux.vda_name; _bfd_elf_swap_verdaux_out (output_bfd, &defaux, (Elf_External_Verdaux *) p); p += sizeof (Elf_External_Verdaux); for (n = t->deps; n != NULL; n = n->next) { if (n->version_needed == NULL) { /* This can happen if there was an error in the version script. */ defaux.vda_name = 0; } else { defaux.vda_name = n->version_needed->name_indx; _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, defaux.vda_name); } if (n->next == NULL) defaux.vda_next = 0; else defaux.vda_next = sizeof (Elf_External_Verdaux); _bfd_elf_swap_verdaux_out (output_bfd, &defaux, (Elf_External_Verdaux *) p); p += sizeof (Elf_External_Verdaux); } } if (! elf_add_dynamic_entry (info, (bfd_vma) DT_VERDEF, (bfd_vma) 0) || ! elf_add_dynamic_entry (info, (bfd_vma) DT_VERDEFNUM, (bfd_vma) cdefs)) return FALSE; elf_tdata (output_bfd)->cverdefs = cdefs; } if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS)) { if (! elf_add_dynamic_entry (info, (bfd_vma) DT_FLAGS, info->flags)) return FALSE; } if (info->flags_1) { if (info->executable) info->flags_1 &= ~ (DF_1_INITFIRST | DF_1_NODELETE | DF_1_NOOPEN); if (! elf_add_dynamic_entry (info, (bfd_vma) DT_FLAGS_1, info->flags_1)) return FALSE; } /* Work out the size of the version reference section. */ s = bfd_get_section_by_name (dynobj, ".gnu.version_r"); BFD_ASSERT (s != NULL); { struct elf_find_verdep_info sinfo; sinfo.output_bfd = output_bfd; sinfo.info = info; sinfo.vers = elf_tdata (output_bfd)->cverdefs; if (sinfo.vers == 0) sinfo.vers = 1; sinfo.failed = FALSE; elf_link_hash_traverse (elf_hash_table (info), _bfd_elf_link_find_version_dependencies, (PTR) &sinfo); if (elf_tdata (output_bfd)->verref == NULL) _bfd_strip_section_from_output (info, s); else { Elf_Internal_Verneed *t; unsigned int size; unsigned int crefs; bfd_byte *p; /* Build the version definition section. */ size = 0; crefs = 0; for (t = elf_tdata (output_bfd)->verref; t != NULL; t = t->vn_nextref) { Elf_Internal_Vernaux *a; size += sizeof (Elf_External_Verneed); ++crefs; for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr) size += sizeof (Elf_External_Vernaux); } s->_raw_size = size; s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size); if (s->contents == NULL) return FALSE; p = s->contents; for (t = elf_tdata (output_bfd)->verref; t != NULL; t = t->vn_nextref) { unsigned int caux; Elf_Internal_Vernaux *a; bfd_size_type indx; caux = 0; for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr) ++caux; t->vn_version = VER_NEED_CURRENT; t->vn_cnt = caux; indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, elf_dt_name (t->vn_bfd) != NULL ? elf_dt_name (t->vn_bfd) : basename (t->vn_bfd->filename), FALSE); if (indx == (bfd_size_type) -1) return FALSE; t->vn_file = indx; t->vn_aux = sizeof (Elf_External_Verneed); if (t->vn_nextref == NULL) t->vn_next = 0; else t->vn_next = (sizeof (Elf_External_Verneed) + caux * sizeof (Elf_External_Vernaux)); _bfd_elf_swap_verneed_out (output_bfd, t, (Elf_External_Verneed *) p); p += sizeof (Elf_External_Verneed); for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr) { a->vna_hash = bfd_elf_hash (a->vna_nodename); indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, a->vna_nodename, FALSE); if (indx == (bfd_size_type) -1) return FALSE; a->vna_name = indx; if (a->vna_nextptr == NULL) a->vna_next = 0; else a->vna_next = sizeof (Elf_External_Vernaux); _bfd_elf_swap_vernaux_out (output_bfd, a, (Elf_External_Vernaux *) p); p += sizeof (Elf_External_Vernaux); } } if (! elf_add_dynamic_entry (info, (bfd_vma) DT_VERNEED, (bfd_vma) 0) || ! elf_add_dynamic_entry (info, (bfd_vma) DT_VERNEEDNUM, (bfd_vma) crefs)) return FALSE; elf_tdata (output_bfd)->cverrefs = crefs; } } /* Assign dynsym indicies. In a shared library we generate a section symbol for each output section, which come first. Next come all of the back-end allocated local dynamic syms, followed by the rest of the global symbols. */ dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info); /* Work out the size of the symbol version section. */ s = bfd_get_section_by_name (dynobj, ".gnu.version"); BFD_ASSERT (s != NULL); if (dynsymcount == 0 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL)) { _bfd_strip_section_from_output (info, s); /* The DYNSYMCOUNT might have changed if we were going to output a dynamic symbol table entry for S. */ dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info); } else { s->_raw_size = dynsymcount * sizeof (Elf_External_Versym); s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size); if (s->contents == NULL) return FALSE; if (! elf_add_dynamic_entry (info, (bfd_vma) DT_VERSYM, (bfd_vma) 0)) return FALSE; } /* Set the size of the .dynsym and .hash sections. We counted the number of dynamic symbols in elf_link_add_object_symbols. We will build the contents of .dynsym and .hash when we build the final symbol table, because until then we do not know the correct value to give the symbols. We built the .dynstr section as we went along in elf_link_add_object_symbols. */ s = bfd_get_section_by_name (dynobj, ".dynsym"); BFD_ASSERT (s != NULL); s->_raw_size = dynsymcount * sizeof (Elf_External_Sym); s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size); if (s->contents == NULL && s->_raw_size != 0) return FALSE; if (dynsymcount != 0) { Elf_Internal_Sym isym; /* The first entry in .dynsym is a dummy symbol. */ isym.st_value = 0; isym.st_size = 0; isym.st_name = 0; isym.st_info = 0; isym.st_other = 0; isym.st_shndx = 0; elf_swap_symbol_out (output_bfd, &isym, (PTR) s->contents, (PTR) 0); } /* Compute the size of the hashing table. As a side effect this computes the hash values for all the names we export. */ bucketcount = compute_bucket_count (info); s = bfd_get_section_by_name (dynobj, ".hash"); BFD_ASSERT (s != NULL); hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize; s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size); s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size); if (s->contents == NULL) return FALSE; bfd_put (8 * hash_entry_size, output_bfd, (bfd_vma) bucketcount, s->contents); bfd_put (8 * hash_entry_size, output_bfd, (bfd_vma) dynsymcount, s->contents + hash_entry_size); elf_hash_table (info)->bucketcount = bucketcount; s = bfd_get_section_by_name (dynobj, ".dynstr"); BFD_ASSERT (s != NULL); elf_finalize_dynstr (output_bfd, info); s->_raw_size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr); for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount) if (! elf_add_dynamic_entry (info, (bfd_vma) DT_NULL, (bfd_vma) 0)) return FALSE; } return TRUE; } /* This function is used to adjust offsets into .dynstr for dynamic symbols. This is called via elf_link_hash_traverse. */ static bfd_boolean elf_adjust_dynstr_offsets PARAMS ((struct elf_link_hash_entry *, PTR)); static bfd_boolean elf_adjust_dynstr_offsets (h, data) struct elf_link_hash_entry *h; PTR data; { struct elf_strtab_hash *dynstr = (struct elf_strtab_hash *) data; if (h->root.type == bfd_link_hash_warning) h = (struct elf_link_hash_entry *) h->root.u.i.link; if (h->dynindx != -1) h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index); return TRUE; } /* Assign string offsets in .dynstr, update all structures referencing them. */ static bfd_boolean elf_finalize_dynstr (output_bfd, info) bfd *output_bfd; struct bfd_link_info *info; { struct elf_link_local_dynamic_entry *entry; struct elf_strtab_hash *dynstr = elf_hash_table (info)->dynstr; bfd *dynobj = elf_hash_table (info)->dynobj; asection *sdyn; bfd_size_type size; Elf_External_Dyn *dyncon, *dynconend; _bfd_elf_strtab_finalize (dynstr); size = _bfd_elf_strtab_size (dynstr); /* Update all .dynamic entries referencing .dynstr strings. */ sdyn = bfd_get_section_by_name (dynobj, ".dynamic"); BFD_ASSERT (sdyn != NULL); dyncon = (Elf_External_Dyn *) sdyn->contents; dynconend = (Elf_External_Dyn *) (sdyn->contents + sdyn->_raw_size); for (; dyncon < dynconend; dyncon++) { Elf_Internal_Dyn dyn; elf_swap_dyn_in (dynobj, dyncon, & dyn); switch (dyn.d_tag) { case DT_STRSZ: dyn.d_un.d_val = size; elf_swap_dyn_out (dynobj, & dyn, dyncon); break; case DT_NEEDED: case DT_SONAME: case DT_RPATH: case DT_RUNPATH: case DT_FILTER: case DT_AUXILIARY: dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val); elf_swap_dyn_out (dynobj, & dyn, dyncon); break; default: break; } } /* Now update local dynamic symbols. */ for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next) entry->isym.st_name = _bfd_elf_strtab_offset (dynstr, entry->isym.st_name); /* And the rest of dynamic symbols. */ elf_link_hash_traverse (elf_hash_table (info), elf_adjust_dynstr_offsets, dynstr); /* Adjust version definitions. */ if (elf_tdata (output_bfd)->cverdefs) { asection *s; bfd_byte *p; bfd_size_type i; Elf_Internal_Verdef def; Elf_Internal_Verdaux defaux; s = bfd_get_section_by_name (dynobj, ".gnu.version_d"); p = (bfd_byte *) s->contents; do { _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p, &def); p += sizeof (Elf_External_Verdef); for (i = 0; i < def.vd_cnt; ++i) { _bfd_elf_swap_verdaux_in (output_bfd, (Elf_External_Verdaux *) p, &defaux); defaux.vda_name = _bfd_elf_strtab_offset (dynstr, defaux.vda_name); _bfd_elf_swap_verdaux_out (output_bfd, &defaux, (Elf_External_Verdaux *) p); p += sizeof (Elf_External_Verdaux); } } while (def.vd_next); } /* Adjust version references. */ if (elf_tdata (output_bfd)->verref) { asection *s; bfd_byte *p; bfd_size_type i; Elf_Internal_Verneed need; Elf_Internal_Vernaux needaux; s = bfd_get_section_by_name (dynobj, ".gnu.version_r"); p = (bfd_byte *) s->contents; do { _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p, &need); need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file); _bfd_elf_swap_verneed_out (output_bfd, &need, (Elf_External_Verneed *) p); p += sizeof (Elf_External_Verneed); for (i = 0; i < need.vn_cnt; ++i) { _bfd_elf_swap_vernaux_in (output_bfd, (Elf_External_Vernaux *) p, &needaux); needaux.vna_name = _bfd_elf_strtab_offset (dynstr, needaux.vna_name); _bfd_elf_swap_vernaux_out (output_bfd, &needaux, (Elf_External_Vernaux *) p); p += sizeof (Elf_External_Vernaux); } } while (need.vn_next); } return TRUE; } /* Final phase of ELF linker. */ /* A structure we use to avoid passing large numbers of arguments. */ struct elf_final_link_info { /* General link information. */ struct bfd_link_info *info; /* Output BFD. */ bfd *output_bfd; /* Symbol string table. */ struct bfd_strtab_hash *symstrtab; /* .dynsym section. */ asection *dynsym_sec; /* .hash section. */ asection *hash_sec; /* symbol version section (.gnu.version). */ asection *symver_sec; /* first SHF_TLS section (if any). */ asection *first_tls_sec; /* Buffer large enough to hold contents of any section. */ bfd_byte *contents; /* Buffer large enough to hold external relocs of any section. */ PTR external_relocs; /* Buffer large enough to hold internal relocs of any section. */ Elf_Internal_Rela *internal_relocs; /* Buffer large enough to hold external local symbols of any input BFD. */ Elf_External_Sym *external_syms; /* And a buffer for symbol section indices. */ Elf_External_Sym_Shndx *locsym_shndx; /* Buffer large enough to hold internal local symbols of any input BFD. */ Elf_Internal_Sym *internal_syms; /* Array large enough to hold a symbol index for each local symbol of any input BFD. */ long *indices; /* Array large enough to hold a section pointer for each local symbol of any input BFD. */ asection **sections; /* Buffer to hold swapped out symbols. */ Elf_External_Sym *symbuf; /* And one for symbol section indices. */ Elf_External_Sym_Shndx *symshndxbuf; /* Number of swapped out symbols in buffer. */ size_t symbuf_count; /* Number of symbols which fit in symbuf. */ size_t symbuf_size; /* And same for symshndxbuf. */ size_t shndxbuf_size; }; static bfd_boolean elf_link_output_sym PARAMS ((struct elf_final_link_info *, const char *, Elf_Internal_Sym *, asection *)); static bfd_boolean elf_link_flush_output_syms PARAMS ((struct elf_final_link_info *)); static bfd_boolean elf_link_output_extsym PARAMS ((struct elf_link_hash_entry *, PTR)); static bfd_boolean elf_link_check_versioned_symbol PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *)); static bfd_boolean elf_link_input_bfd PARAMS ((struct elf_final_link_info *, bfd *)); static bfd_boolean elf_reloc_link_order PARAMS ((bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *)); /* This struct is used to pass information to elf_link_output_extsym. */ struct elf_outext_info { bfd_boolean failed; bfd_boolean localsyms; struct elf_final_link_info *finfo; }; /* When performing a relocateable link, the input relocations are preserved. But, if they reference global symbols, the indices referenced must be updated. Update all the relocations in REL_HDR (there are COUNT of them), using the data in REL_HASH. */ static void elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash) bfd *abfd; Elf_Internal_Shdr *rel_hdr; unsigned int count; struct elf_link_hash_entry **rel_hash; { unsigned int i; struct elf_backend_data *bed = get_elf_backend_data (abfd); bfd_byte *erela; void (*swap_in) PARAMS ((bfd *, const bfd_byte *, Elf_Internal_Rela *)); void (*swap_out) PARAMS ((bfd *, const Elf_Internal_Rela *, bfd_byte *)); if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel)) { swap_in = bed->s->swap_reloc_in; swap_out = bed->s->swap_reloc_out; } else if (rel_hdr->sh_entsize == sizeof (Elf_External_Rela)) { swap_in = bed->s->swap_reloca_in; swap_out = bed->s->swap_reloca_out; } else abort (); if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL) abort (); erela = rel_hdr->contents; for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize) { Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL]; unsigned int j; if (*rel_hash == NULL) continue; BFD_ASSERT ((*rel_hash)->indx >= 0); (*swap_in) (abfd, erela, irela); for (j = 0; j < bed->s->int_rels_per_ext_rel; j++) irela[j].r_info = ELF_R_INFO ((*rel_hash)->indx, ELF_R_TYPE (irela[j].r_info)); (*swap_out) (abfd, irela, erela); } } struct elf_link_sort_rela { bfd_vma offset; enum elf_reloc_type_class type; /* We use this as an array of size int_rels_per_ext_rel. */ Elf_Internal_Rela rela[1]; }; static int elf_link_sort_cmp1 (A, B) const PTR A; const PTR B; { struct elf_link_sort_rela *a = (struct elf_link_sort_rela *) A; struct elf_link_sort_rela *b = (struct elf_link_sort_rela *) B; int relativea, relativeb; relativea = a->type == reloc_class_relative; relativeb = b->type == reloc_class_relative; if (relativea < relativeb) return 1; if (relativea > relativeb) return -1; if (ELF_R_SYM (a->rela->r_info) < ELF_R_SYM (b->rela->r_info)) return -1; if (ELF_R_SYM (a->rela->r_info) > ELF_R_SYM (b->rela->r_info)) return 1; if (a->rela->r_offset < b->rela->r_offset) return -1; if (a->rela->r_offset > b->rela->r_offset) return 1; return 0; } static int elf_link_sort_cmp2 (A, B) const PTR A; const PTR B; { struct elf_link_sort_rela *a = (struct elf_link_sort_rela *) A; struct elf_link_sort_rela *b = (struct elf_link_sort_rela *) B; int copya, copyb; if (a->offset < b->offset) return -1; if (a->offset > b->offset) return 1; copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt); copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt); if (copya < copyb) return -1; if (copya > copyb) return 1; if (a->rela->r_offset < b->rela->r_offset) return -1; if (a->rela->r_offset > b->rela->r_offset) return 1; return 0; } static size_t elf_link_sort_relocs (abfd, info, psec) bfd *abfd; struct bfd_link_info *info; asection **psec; { bfd *dynobj = elf_hash_table (info)->dynobj; asection *reldyn, *o; bfd_size_type count, size; size_t i, ret, sort_elt, ext_size; bfd_byte *sort, *s_non_relative, *p; struct elf_link_sort_rela *sq; struct elf_backend_data *bed = get_elf_backend_data (abfd); int i2e = bed->s->int_rels_per_ext_rel; void (*swap_in) PARAMS ((bfd *, const bfd_byte *, Elf_Internal_Rela *)); void (*swap_out) PARAMS ((bfd *, const Elf_Internal_Rela *, bfd_byte *)); reldyn = bfd_get_section_by_name (abfd, ".rela.dyn"); if (reldyn == NULL || reldyn->_raw_size == 0) { reldyn = bfd_get_section_by_name (abfd, ".rel.dyn"); if (reldyn == NULL || reldyn->_raw_size == 0) return 0; ext_size = sizeof (Elf_External_Rel); swap_in = bed->s->swap_reloc_in; swap_out = bed->s->swap_reloc_out; } else { ext_size = sizeof (Elf_External_Rela); swap_in = bed->s->swap_reloca_in; swap_out = bed->s->swap_reloca_out; } count = reldyn->_raw_size / ext_size; size = 0; for (o = dynobj->sections; o != NULL; o = o->next) if ((o->flags & (SEC_HAS_CONTENTS|SEC_LINKER_CREATED)) == (SEC_HAS_CONTENTS|SEC_LINKER_CREATED) && o->output_section == reldyn) size += o->_raw_size; if (size != reldyn->_raw_size) return 0; sort_elt = (sizeof (struct elf_link_sort_rela) + (i2e - 1) * sizeof (Elf_Internal_Rela)); sort = bfd_zmalloc (sort_elt * count); if (sort == NULL) { (*info->callbacks->warning) (info, _("Not enough memory to sort relocations"), 0, abfd, 0, (bfd_vma) 0); return 0; } for (o = dynobj->sections; o != NULL; o = o->next) if ((o->flags & (SEC_HAS_CONTENTS|SEC_LINKER_CREATED)) == (SEC_HAS_CONTENTS|SEC_LINKER_CREATED) && o->output_section == reldyn) { bfd_byte *erel, *erelend; erel = o->contents; erelend = o->contents + o->_raw_size; p = sort + o->output_offset / ext_size * sort_elt; while (erel < erelend) { struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p; (*swap_in) (abfd, erel, s->rela); s->type = (*bed->elf_backend_reloc_type_class) (s->rela); p += sort_elt; erel += ext_size; } } qsort (sort, (size_t) count, sort_elt, elf_link_sort_cmp1); for (i = 0, p = sort; i < count; i++, p += sort_elt) { struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p; if (s->type != reloc_class_relative) break; } ret = i; s_non_relative = p; sq = (struct elf_link_sort_rela *) s_non_relative; for (; i < count; i++, p += sort_elt) { struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p; if (ELF_R_SYM (sp->rela->r_info) != ELF_R_SYM (sq->rela->r_info)) sq = sp; sp->offset = sq->rela->r_offset; } qsort (s_non_relative, (size_t) count - ret, sort_elt, elf_link_sort_cmp2); for (o = dynobj->sections; o != NULL; o = o->next) if ((o->flags & (SEC_HAS_CONTENTS|SEC_LINKER_CREATED)) == (SEC_HAS_CONTENTS|SEC_LINKER_CREATED) && o->output_section == reldyn) { bfd_byte *erel, *erelend; erel = o->contents; erelend = o->contents + o->_raw_size; p = sort + o->output_offset / ext_size * sort_elt; while (erel < erelend) { struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p; (*swap_out) (abfd, s->rela, erel); p += sort_elt; erel += ext_size; } } free (sort); *psec = reldyn; return ret; } /* Do the final step of an ELF link. */ bfd_boolean elf_bfd_final_link (abfd, info) bfd *abfd; struct bfd_link_info *info; { bfd_boolean dynamic; bfd_boolean emit_relocs; bfd *dynobj; struct elf_final_link_info finfo; register asection *o; register struct bfd_link_order *p; register 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_sym_count; bfd_size_type max_sym_shndx_count; file_ptr off; Elf_Internal_Sym elfsym; unsigned int i; Elf_Internal_Shdr *symtab_hdr; Elf_Internal_Shdr *symtab_shndx_hdr; Elf_Internal_Shdr *symstrtab_hdr; struct elf_backend_data *bed = get_elf_backend_data (abfd); struct elf_outext_info eoinfo; bfd_boolean merged; size_t relativecount = 0; asection *reldyn = 0; bfd_size_type amt; if (! is_elf_hash_table (info)) return FALSE; if (info->shared) abfd->flags |= DYNAMIC; dynamic = elf_hash_table (info)->dynamic_sections_created; dynobj = elf_hash_table (info)->dynobj; emit_relocs = (info->relocateable || info->emitrelocations || bed->elf_backend_emit_relocs); finfo.info = info; finfo.output_bfd = abfd; finfo.symstrtab = elf_stringtab_init (); if (finfo.symstrtab == NULL) return FALSE; if (! dynamic) { finfo.dynsym_sec = NULL; finfo.hash_sec = NULL; finfo.symver_sec = NULL; } else { finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym"); finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash"); BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL); finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version"); /* Note that it is OK if symver_sec is NULL. */ } finfo.contents = NULL; finfo.external_relocs = NULL; finfo.internal_relocs = NULL; finfo.external_syms = NULL; finfo.locsym_shndx = NULL; finfo.internal_syms = NULL; finfo.indices = NULL; finfo.sections = NULL; finfo.symbuf = NULL; finfo.symshndxbuf = NULL; finfo.symbuf_count = 0; finfo.shndxbuf_size = 0; finfo.first_tls_sec = NULL; for (o = abfd->sections; o != (asection *) NULL; o = o->next) if ((o->flags & SEC_THREAD_LOCAL) != 0 && (o->flags & SEC_LOAD) != 0) { finfo.first_tls_sec = o; break; } /* Count up the number of relocations we will output for each output section, so that we know the sizes of the reloc sections. We also figure out some maximum sizes. */ max_contents_size = 0; max_external_reloc_size = 0; max_internal_reloc_count = 0; max_sym_count = 0; max_sym_shndx_count = 0; merged = FALSE; for (o = abfd->sections; o != (asection *) NULL; o = o->next) { struct bfd_elf_section_data *esdo = elf_section_data (o); o->reloc_count = 0; for (p = o->link_order_head; p != NULL; p = p->next) { unsigned int reloc_count = 0; struct bfd_elf_section_data *esdi = NULL; unsigned int *rel_count1; if (p->type == bfd_section_reloc_link_order || p->type == bfd_symbol_reloc_link_order) reloc_count = 1; else if (p->type == bfd_indirect_link_order) { asection *sec; sec = p->u.indirect.section; esdi = elf_section_data (sec); /* Mark all sections which are to be included in the link. This will normally be every section. We need to do this so that we can identify any sections which the linker has decided to not include. */ sec->linker_mark = TRUE; if (sec->flags & SEC_MERGE) merged = TRUE; if (info->relocateable || info->emitrelocations) reloc_count = sec->reloc_count; else if (bed->elf_backend_count_relocs) { Elf_Internal_Rela * relocs; relocs = _bfd_elf_link_read_relocs (abfd, sec, (PTR) NULL, (Elf_Internal_Rela *) NULL, info->keep_memory); reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs); if (elf_section_data (o)->relocs != relocs) free (relocs); } if (sec->_raw_size > max_contents_size) max_contents_size = sec->_raw_size; if (sec->_cooked_size > max_contents_size) max_contents_size = sec->_cooked_size; /* We are interested in just local symbols, not all symbols. */ if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour && (sec->owner->flags & DYNAMIC) == 0) { size_t sym_count; if (elf_bad_symtab (sec->owner)) sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size / sizeof (Elf_External_Sym)); else sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info; if (sym_count > max_sym_count) max_sym_count = sym_count; if (sym_count > max_sym_shndx_count && elf_symtab_shndx (sec->owner) != 0) max_sym_shndx_count = sym_count; if ((sec->flags & SEC_RELOC) != 0) { size_t ext_size; ext_size = elf_section_data (sec)->rel_hdr.sh_size; if (ext_size > max_external_reloc_size) max_external_reloc_size = ext_size; if (sec->reloc_count > max_internal_reloc_count) max_internal_reloc_count = sec->reloc_count; } } } if (reloc_count == 0) continue; o->reloc_count += reloc_count; /* MIPS may have a mix of REL and RELA relocs on sections. To support this curious ABI we keep reloc counts in elf_section_data too. We must be careful to add the relocations from the input section to the right output count. FIXME: Get rid of one count. We have o->reloc_count == esdo->rel_count + esdo->rel_count2. */ rel_count1 = &esdo->rel_count; if (esdi != NULL) { bfd_boolean same_size; bfd_size_type entsize1; entsize1 = esdi->rel_hdr.sh_entsize; BFD_ASSERT (entsize1 == sizeof (Elf_External_Rel) || entsize1 == sizeof (Elf_External_Rela)); same_size = (!o->use_rela_p == (entsize1 == sizeof (Elf_External_Rel))); if (!same_size) rel_count1 = &esdo->rel_count2; if (esdi->rel_hdr2 != NULL) { bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize; unsigned int alt_count; unsigned int *rel_count2; BFD_ASSERT (entsize2 != entsize1 && (entsize2 == sizeof (Elf_External_Rel) || entsize2 == sizeof (Elf_External_Rela))); rel_count2 = &esdo->rel_count2; if (!same_size) rel_count2 = &esdo->rel_count; /* The following is probably too simplistic if the backend counts output relocs unusually. */ BFD_ASSERT (bed->elf_backend_count_relocs == NULL); alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2); *rel_count2 += alt_count; reloc_count -= alt_count; } } *rel_count1 += reloc_count; } if (o->reloc_count > 0) o->flags |= SEC_RELOC; else { /* Explicitly clear the SEC_RELOC flag. The linker tends to set it (this is probably a bug) and if it is set assign_section_numbers will create a reloc section. */ o->flags &=~ SEC_RELOC; } /* If the SEC_ALLOC flag is not set, force the section VMA to zero. This is done in elf_fake_sections as well, but forcing the VMA to 0 here will ensure that relocs against these sections are handled correctly. */ if ((o->flags & SEC_ALLOC) == 0 && ! o->user_set_vma) o->vma = 0; } if (! info->relocateable && merged) elf_link_hash_traverse (elf_hash_table (info), _bfd_elf_link_sec_merge_syms, (PTR) abfd); /* Figure out the file positions for everything but the symbol table and the relocs. We set symcount to force assign_section_numbers to create a symbol table. */ bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1; BFD_ASSERT (! abfd->output_has_begun); if (! _bfd_elf_compute_section_file_positions (abfd, info)) goto error_return; /* That created the reloc sections. Set their sizes, and assign them file positions, and allocate some buffers. */ for (o = abfd->sections; o != NULL; o = o->next) { if ((o->flags & SEC_RELOC) != 0) { if (!(_bfd_elf_link_size_reloc_section (abfd, &elf_section_data (o)->rel_hdr, o))) goto error_return; if (elf_section_data (o)->rel_hdr2 && !(_bfd_elf_link_size_reloc_section (abfd, elf_section_data (o)->rel_hdr2, o))) goto error_return; } /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them to count upwards while actually outputting the relocations. */ elf_section_data (o)->rel_count = 0; elf_section_data (o)->rel_count2 = 0; } _bfd_elf_assign_file_positions_for_relocs (abfd); /* We have now assigned file positions for all the sections except .symtab and .strtab. We start the .symtab section at the current file position, and write directly to it. We build the .strtab section in memory. */ bfd_get_symcount (abfd) = 0; symtab_hdr = &elf_tdata (abfd)->symtab_hdr; /* sh_name is set in prep_headers. */ symtab_hdr->sh_type = SHT_SYMTAB; /* sh_flags, sh_addr and sh_size all start off zero. */ symtab_hdr->sh_entsize = sizeof (Elf_External_Sym); /* sh_link is set in assign_section_numbers. */ /* sh_info is set below. */ /* sh_offset is set just below. */ symtab_hdr->sh_addralign = 1 << bed->s->log_file_align; off = elf_tdata (abfd)->next_file_pos; off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE); /* Note that at this point elf_tdata (abfd)->next_file_pos is incorrect. We do not yet know the size of the .symtab section. We correct next_file_pos below, after we do know the size. */ /* Allocate a buffer to hold swapped out symbols. This is to avoid continuously seeking to the right position in the file. */ if (! info->keep_memory || max_sym_count < 20) finfo.symbuf_size = 20; else finfo.symbuf_size = max_sym_count; amt = finfo.symbuf_size; amt *= sizeof (Elf_External_Sym); finfo.symbuf = (Elf_External_Sym *) bfd_malloc (amt); if (finfo.symbuf == NULL) goto error_return; if (elf_numsections (abfd) > SHN_LORESERVE) { /* Wild guess at number of output symbols. realloc'd as needed. */ amt = 2 * max_sym_count + elf_numsections (abfd) + 1000; finfo.shndxbuf_size = amt; amt *= sizeof (Elf_External_Sym_Shndx); finfo.symshndxbuf = (Elf_External_Sym_Shndx *) bfd_zmalloc (amt); if (finfo.symshndxbuf == NULL) goto error_return; } /* Start writing out the symbol table. The first symbol is always a dummy symbol. */ if (info->strip != strip_all || emit_relocs) { elfsym.st_value = 0; elfsym.st_size = 0; elfsym.st_info = 0; elfsym.st_other = 0; elfsym.st_shndx = SHN_UNDEF; if (! elf_link_output_sym (&finfo, (const char *) NULL, &elfsym, bfd_und_section_ptr)) goto error_return; } #if 0 /* Some standard ELF linkers do this, but we don't because it causes bootstrap comparison failures. */ /* Output a file symbol for the output file as the second symbol. We output this even if we are discarding local symbols, although I'm not sure if this is correct. */ elfsym.st_value = 0; elfsym.st_size = 0; elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE); elfsym.st_other = 0; elfsym.st_shndx = SHN_ABS; if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd), &elfsym, bfd_abs_section_ptr)) goto error_return; #endif /* Output a symbol for each section. We output these even if we are discarding local symbols, since they are used for relocs. These symbols have no names. We store the index of each one in the index field of the section, so that we can find it again when outputting relocs. */ if (info->strip != strip_all || emit_relocs) { elfsym.st_size = 0; elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION); elfsym.st_other = 0; for (i = 1; i < elf_numsections (abfd); i++) { o = section_from_elf_index (abfd, i); if (o != NULL) o->target_index = bfd_get_symcount (abfd); elfsym.st_shndx = i; if (info->relocateable || o == NULL) elfsym.st_value = 0; else elfsym.st_value = o->vma; if (! elf_link_output_sym (&finfo, (const char *) NULL, &elfsym, o)) goto error_return; if (i == SHN_LORESERVE - 1) i += SHN_HIRESERVE + 1 - SHN_LORESERVE; } } /* Allocate some memory to hold information read in from the input files. */ if (max_contents_size != 0) { finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size); if (finfo.contents == NULL) goto error_return; } if (max_external_reloc_size != 0) { finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size); if (finfo.external_relocs == NULL) goto error_return; } if (max_internal_reloc_count != 0) { amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel; amt *= sizeof (Elf_Internal_Rela); finfo.internal_relocs = (Elf_Internal_Rela *) bfd_malloc (amt); if (finfo.internal_relocs == NULL) goto error_return; } if (max_sym_count != 0) { amt = max_sym_count * sizeof (Elf_External_Sym); finfo.external_syms = (Elf_External_Sym *) bfd_malloc (amt); if (finfo.external_syms == NULL) goto error_return; amt = max_sym_count * sizeof (Elf_Internal_Sym); finfo.internal_syms = (Elf_Internal_Sym *) bfd_malloc (amt); if (finfo.internal_syms == NULL) goto error_return; amt = max_sym_count * sizeof (long); finfo.indices = (long *) bfd_malloc (amt); if (finfo.indices == NULL) goto error_return; amt = max_sym_count * sizeof (asection *); finfo.sections = (asection **) bfd_malloc (amt); if (finfo.sections == NULL) goto error_return; } if (max_sym_shndx_count != 0) { amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx); finfo.locsym_shndx = (Elf_External_Sym_Shndx *) bfd_malloc (amt); if (finfo.locsym_shndx == NULL) goto error_return; } if (finfo.first_tls_sec) { unsigned int align = 0; bfd_vma base = finfo.first_tls_sec->vma, end = 0; asection *sec; for (sec = finfo.first_tls_sec; sec && (sec->flags & SEC_THREAD_LOCAL); sec = sec->next) { bfd_vma size = sec->_raw_size; if (bfd_get_section_alignment (abfd, sec) > align) align = bfd_get_section_alignment (abfd, sec); if (sec->_raw_size == 0 && (sec->flags & SEC_HAS_CONTENTS) == 0) { struct bfd_link_order *o; size = 0; for (o = sec->link_order_head; o != NULL; o = o->next) if (size < o->offset + o->size) size = o->offset + o->size; } end = sec->vma + size; } elf_hash_table (info)->tls_segment = bfd_zalloc (abfd, sizeof (struct elf_link_tls_segment)); if (elf_hash_table (info)->tls_segment == NULL) goto error_return; elf_hash_table (info)->tls_segment->start = base; elf_hash_table (info)->tls_segment->size = end - base; elf_hash_table (info)->tls_segment->align = align; } /* Since ELF permits relocations to be against local symbols, we must have the local symbols available when we do the relocations. Since we would rather only read the local symbols once, and we would rather not keep them in memory, we handle all the relocations for a single input file at the same time. Unfortunately, there is no way to know the total number of local symbols until we have seen all of them, and the local symbol indices precede the global symbol indices. This means that when we are generating relocateable output, and we see a reloc against a global symbol, we can not know the symbol index until we have finished examining all the local symbols to see which ones we are going to output. To deal with this, we keep the relocations in memory, and don't output them until the end of the link. This is an unfortunate waste of memory, but I don't see a good way around it. Fortunately, it only happens when performing a relocateable link, which is not the common case. FIXME: If keep_memory is set we could write the relocs out and then read them again; I don't know how bad the memory loss will be. */ for (sub = info->input_bfds; sub != NULL; sub = sub->link_next) sub->output_has_begun = FALSE; for (o = abfd->sections; o != NULL; o = o->next) { for (p = o->link_order_head; p != NULL; p = p->next) { if (p->type == bfd_indirect_link_order && (bfd_get_flavour ((sub = p->u.indirect.section->owner)) == bfd_target_elf_flavour) && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass) { if (! sub->output_has_begun) { if (! elf_link_input_bfd (&finfo, sub)) goto error_return; sub->output_has_begun = TRUE; } } else if (p->type == bfd_section_reloc_link_order || p->type == bfd_symbol_reloc_link_order) { if (! elf_reloc_link_order (abfd, info, o, p)) goto error_return; } else { if (! _bfd_default_link_order (abfd, info, o, p)) goto error_return; } } } /* Output any global symbols that got converted to local in a version script or due to symbol visibility. We do this in a separate step since ELF requires all local symbols to appear prior to any global symbols. FIXME: We should only do this if some global symbols were, in fact, converted to become local. FIXME: Will this work correctly with the Irix 5 linker? */ eoinfo.failed = FALSE; eoinfo.finfo = &finfo; eoinfo.localsyms = TRUE; elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym, (PTR) &eoinfo); if (eoinfo.failed) return FALSE; /* That wrote out all the local symbols. Finish up the symbol table with the global symbols. Even if we want to strip everything we can, we still need to deal with those global symbols that got converted to local in a version script. */ /* The sh_info field records the index of the first non local symbol. */ symtab_hdr->sh_info = bfd_get_symcount (abfd); if (dynamic && finfo.dynsym_sec->output_section != bfd_abs_section_ptr) { Elf_Internal_Sym sym; Elf_External_Sym *dynsym = (Elf_External_Sym *) finfo.dynsym_sec->contents; long last_local = 0; /* Write out the section symbols for the output sections. */ if (info->shared) { asection *s; sym.st_size = 0; sym.st_name = 0; sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION); sym.st_other = 0; for (s = abfd->sections; s != NULL; s = s->next) { int indx; Elf_External_Sym *dest; indx = elf_section_data (s)->this_idx; BFD_ASSERT (indx > 0); sym.st_shndx = indx; sym.st_value = s->vma; dest = dynsym + elf_section_data (s)->dynindx; elf_swap_symbol_out (abfd, &sym, (PTR) dest, (PTR) 0); } last_local = bfd_count_sections (abfd); } /* Write out the local dynsyms. */ if (elf_hash_table (info)->dynlocal) { struct elf_link_local_dynamic_entry *e; for (e = elf_hash_table (info)->dynlocal; e ; e = e->next) { asection *s; Elf_External_Sym *dest; sym.st_size = e->isym.st_size; sym.st_other = e->isym.st_other; /* Copy the internal symbol as is. Note that we saved a word of storage and overwrote the original st_name with the dynstr_index. */ sym = e->isym; if (e->isym.st_shndx != SHN_UNDEF && (e->isym.st_shndx < SHN_LORESERVE || e->isym.st_shndx > SHN_HIRESERVE)) { s = bfd_section_from_elf_index (e->input_bfd, e->isym.st_shndx); sym.st_shndx = elf_section_data (s->output_section)->this_idx; sym.st_value = (s->output_section->vma + s->output_offset + e->isym.st_value); } if (last_local < e->dynindx) last_local = e->dynindx; dest = dynsym + e->dynindx; elf_swap_symbol_out (abfd, &sym, (PTR) dest, (PTR) 0); } } elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info = last_local + 1; } /* We get the global symbols from the hash table. */ eoinfo.failed = FALSE; eoinfo.localsyms = FALSE; eoinfo.finfo = &finfo; elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym, (PTR) &eoinfo); if (eoinfo.failed) return FALSE; /* If backend needs to output some symbols not present in the hash table, do it now. */ if (bed->elf_backend_output_arch_syms) { typedef bfd_boolean (*out_sym_func) PARAMS ((PTR, const char *, Elf_Internal_Sym *, asection *)); if (! ((*bed->elf_backend_output_arch_syms) (abfd, info, (PTR) &finfo, (out_sym_func) elf_link_output_sym))) return FALSE; } /* Flush all symbols to the file. */ if (! elf_link_flush_output_syms (&finfo)) return FALSE; /* Now we know the size of the symtab section. */ off += symtab_hdr->sh_size; symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr; if (symtab_shndx_hdr->sh_name != 0) { symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX; symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx); symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx); amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx); symtab_shndx_hdr->sh_size = amt; off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr, off, TRUE); if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0 || (bfd_bwrite ((PTR) finfo.symshndxbuf, amt, abfd) != amt)) return FALSE; } /* Finish up and write out the symbol string table (.strtab) section. */ symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr; /* sh_name was set in prep_headers. */ symstrtab_hdr->sh_type = SHT_STRTAB; symstrtab_hdr->sh_flags = 0; symstrtab_hdr->sh_addr = 0; symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab); symstrtab_hdr->sh_entsize = 0; symstrtab_hdr->sh_link = 0; symstrtab_hdr->sh_info = 0; /* sh_offset is set just below. */ symstrtab_hdr->sh_addralign = 1; off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE); elf_tdata (abfd)->next_file_pos = off; if (bfd_get_symcount (abfd) > 0) { if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab)) return FALSE; } /* Adjust the relocs to have the correct symbol indices. */ for (o = abfd->sections; o != NULL; o = o->next) { if ((o->flags & SEC_RELOC) == 0) continue; elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr, elf_section_data (o)->rel_count, elf_section_data (o)->rel_hashes); if (elf_section_data (o)->rel_hdr2 != NULL) elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2, elf_section_data (o)->rel_count2, (elf_section_data (o)->rel_hashes + elf_section_data (o)->rel_count)); /* Set the reloc_count field to 0 to prevent write_relocs from trying to swap the relocs out itself. */ o->reloc_count = 0; } if (dynamic && info->combreloc && dynobj != NULL) relativecount = elf_link_sort_relocs (abfd, info, &reldyn); /* If we are linking against a dynamic object, or generating a shared library, finish up the dynamic linking information. */ if (dynamic) { Elf_External_Dyn *dyncon, *dynconend; /* Fix up .dynamic entries. */ o = bfd_get_section_by_name (dynobj, ".dynamic"); BFD_ASSERT (o != NULL); dyncon = (Elf_External_Dyn *) o->contents; dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size); for (; dyncon < dynconend; dyncon++) { Elf_Internal_Dyn dyn; const char *name; unsigned int type; elf_swap_dyn_in (dynobj, dyncon, &dyn); switch (dyn.d_tag) { default: break; case DT_NULL: if (relativecount > 0 && dyncon + 1 < dynconend) { switch (elf_section_data (reldyn)->this_hdr.sh_type) { case SHT_REL: dyn.d_tag = DT_RELCOUNT; break; case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break; default: break; } if (dyn.d_tag != DT_NULL) { dyn.d_un.d_val = relativecount; elf_swap_dyn_out (dynobj, &dyn, dyncon); relativecount = 0; } } break; case DT_INIT: name = info->init_function; goto get_sym; case DT_FINI: name = info->fini_function; get_sym: { struct elf_link_hash_entry *h; h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, TRUE); if (h != NULL && (h->root.type == bfd_link_hash_defined || h->root.type == bfd_link_hash_defweak)) { dyn.d_un.d_val = h->root.u.def.value; o = h->root.u.def.section; if (o->output_section != NULL) dyn.d_un.d_val += (o->output_section->vma + o->output_offset); else { /* The symbol is imported from another shared library and does not apply to this one. */ dyn.d_un.d_val = 0; } elf_swap_dyn_out (dynobj, &dyn, dyncon); } } break; case DT_PREINIT_ARRAYSZ: name = ".preinit_array"; goto get_size; case DT_INIT_ARRAYSZ: name = ".init_array"; goto get_size; case DT_FINI_ARRAYSZ: name = ".fini_array"; get_size: o = bfd_get_section_by_name (abfd, name); if (o == NULL) { (*_bfd_error_handler) (_("%s: could not find output section %s"), bfd_get_filename (abfd), name); goto error_return; } if (o->_raw_size == 0) (*_bfd_error_handler) (_("warning: %s section has zero size"), name); dyn.d_un.d_val = o->_raw_size; elf_swap_dyn_out (dynobj, &dyn, dyncon); break; case DT_PREINIT_ARRAY: name = ".preinit_array"; goto get_vma; case DT_INIT_ARRAY: name = ".init_array"; goto get_vma; case DT_FINI_ARRAY: name = ".fini_array"; goto get_vma; case DT_HASH: name = ".hash"; goto get_vma; case DT_STRTAB: name = ".dynstr"; goto get_vma; case DT_SYMTAB: name = ".dynsym"; goto get_vma; case DT_VERDEF: name = ".gnu.version_d"; goto get_vma; case DT_VERNEED: name = ".gnu.version_r"; goto get_vma; case DT_VERSYM: name = ".gnu.version"; get_vma: o = bfd_get_section_by_name (abfd, name); if (o == NULL) { (*_bfd_error_handler) (_("%s: could not find output section %s"), bfd_get_filename (abfd), name); goto error_return; } dyn.d_un.d_ptr = o->vma; elf_swap_dyn_out (dynobj, &dyn, dyncon); break; case DT_REL: case DT_RELA: case DT_RELSZ: case DT_RELASZ: if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ) type = SHT_REL; else type = SHT_RELA; dyn.d_un.d_val = 0; for (i = 1; i < elf_numsections (abfd); i++) { Elf_Internal_Shdr *hdr; hdr = elf_elfsections (abfd)[i]; if (hdr->sh_type == type && (hdr->sh_flags & SHF_ALLOC) != 0) { if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ) dyn.d_un.d_val += hdr->sh_size; else { if (dyn.d_un.d_val == 0 || hdr->sh_addr < dyn.d_un.d_val) dyn.d_un.d_val = hdr->sh_addr; } } } elf_swap_dyn_out (dynobj, &dyn, dyncon); break; } } } /* If we have created any dynamic sections, then output them. */ if (dynobj != NULL) { if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info)) goto error_return; for (o = dynobj->sections; o != NULL; o = o->next) { if ((o->flags & SEC_HAS_CONTENTS) == 0 || o->_raw_size == 0 || o->output_section == bfd_abs_section_ptr) continue; if ((o->flags & SEC_LINKER_CREATED) == 0) { /* At this point, we are only interested in sections created by _bfd_elf_link_create_dynamic_sections. */ continue; } if ((elf_section_data (o->output_section)->this_hdr.sh_type != SHT_STRTAB) || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0) { if (! bfd_set_section_contents (abfd, o->output_section, o->contents, (file_ptr) o->output_offset, o->_raw_size)) goto error_return; } else { /* The contents of the .dynstr section are actually in a stringtab. */ off = elf_section_data (o->output_section)->this_hdr.sh_offset; if (bfd_seek (abfd, off, SEEK_SET) != 0 || ! _bfd_elf_strtab_emit (abfd, elf_hash_table (info)->dynstr)) goto error_return; } } } if (info->relocateable) { bfd_boolean failed = FALSE; bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed); if (failed) goto error_return; } /* If we have optimized stabs strings, output them. */ if (elf_hash_table (info)->stab_info != NULL) { if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info)) goto error_return; } if (info->eh_frame_hdr) { if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info)) goto error_return; } if (finfo.symstrtab != NULL) _bfd_stringtab_free (finfo.symstrtab); if (finfo.contents != NULL) free (finfo.contents); if (finfo.external_relocs != NULL) free (finfo.external_relocs); if (finfo.internal_relocs != NULL) free (finfo.internal_relocs); if (finfo.external_syms != NULL) free (finfo.external_syms); if (finfo.locsym_shndx != NULL) free (finfo.locsym_shndx); if (finfo.internal_syms != NULL) free (finfo.internal_syms); if (finfo.indices != NULL) free (finfo.indices); if (finfo.sections != NULL) free (finfo.sections); if (finfo.symbuf != NULL) free (finfo.symbuf); if (finfo.symshndxbuf != NULL) free (finfo.symshndxbuf); for (o = abfd->sections; o != NULL; o = o->next) { if ((o->flags & SEC_RELOC) != 0 && elf_section_data (o)->rel_hashes != NULL) free (elf_section_data (o)->rel_hashes); } elf_tdata (abfd)->linker = TRUE; return TRUE; error_return: if (finfo.symstrtab != NULL) _bfd_stringtab_free (finfo.symstrtab); if (finfo.contents != NULL) free (finfo.contents); if (finfo.external_relocs != NULL) free (finfo.external_relocs); if (finfo.internal_relocs != NULL) free (finfo.internal_relocs); if (finfo.external_syms != NULL) free (finfo.external_syms); if (finfo.locsym_shndx != NULL) free (finfo.locsym_shndx); if (finfo.internal_syms != NULL) free (finfo.internal_syms); if (finfo.indices != NULL) free (finfo.indices); if (finfo.sections != NULL) free (finfo.sections); if (finfo.symbuf != NULL) free (finfo.symbuf); if (finfo.symshndxbuf != NULL) free (finfo.symshndxbuf); for (o = abfd->sections; o != NULL; o = o->next) { if ((o->flags & SEC_RELOC) != 0 && elf_section_data (o)->rel_hashes != NULL) free (elf_section_data (o)->rel_hashes); } return FALSE; } /* Add a symbol to the output symbol table. */ static bfd_boolean elf_link_output_sym (finfo, name, elfsym, input_sec) struct elf_final_link_info *finfo; const char *name; Elf_Internal_Sym *elfsym; asection *input_sec; { Elf_External_Sym *dest; Elf_External_Sym_Shndx *destshndx; bfd_boolean (*output_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *info, const char *, Elf_Internal_Sym *, asection *)); output_symbol_hook = get_elf_backend_data (finfo->output_bfd)-> elf_backend_link_output_symbol_hook; if (output_symbol_hook != NULL) { if (! ((*output_symbol_hook) (finfo->output_bfd, finfo->info, name, elfsym, input_sec))) return FALSE; } if (name == (const char *) NULL || *name == '\0') elfsym->st_name = 0; else if (input_sec->flags & SEC_EXCLUDE) elfsym->st_name = 0; else { elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab, name, TRUE, FALSE); if (elfsym->st_name == (unsigned long) -1) return FALSE; } if (finfo->symbuf_count >= finfo->symbuf_size) { if (! elf_link_flush_output_syms (finfo)) return FALSE; } dest = finfo->symbuf + finfo->symbuf_count; destshndx = finfo->symshndxbuf; if (destshndx != NULL) { if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size) { bfd_size_type amt; amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx); finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2); if (destshndx == NULL) return FALSE; memset ((char *) destshndx + amt, 0, amt); finfo->shndxbuf_size *= 2; } destshndx += bfd_get_symcount (finfo->output_bfd); } elf_swap_symbol_out (finfo->output_bfd, elfsym, (PTR) dest, (PTR) destshndx); finfo->symbuf_count += 1; bfd_get_symcount (finfo->output_bfd) += 1; return TRUE; } /* Flush the output symbols to the file. */ static bfd_boolean elf_link_flush_output_syms (finfo) struct elf_final_link_info *finfo; { if (finfo->symbuf_count > 0) { Elf_Internal_Shdr *hdr; file_ptr pos; bfd_size_type amt; hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr; pos = hdr->sh_offset + hdr->sh_size; amt = finfo->symbuf_count * sizeof (Elf_External_Sym); if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0 || bfd_bwrite ((PTR) finfo->symbuf, amt, finfo->output_bfd) != amt) return FALSE; hdr->sh_size += amt; finfo->symbuf_count = 0; } return TRUE; } /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in allowing an unsatisfied unversioned symbol in the DSO to match a versioned symbol that would normally require an explicit version. We also handle the case that a DSO references a hidden symbol which may be satisfied by a versioned symbol in another DSO. */ static bfd_boolean elf_link_check_versioned_symbol (info, h) struct bfd_link_info *info; struct elf_link_hash_entry *h; { bfd *abfd; struct elf_link_loaded_list *loaded; if (info->hash->creator->flavour != bfd_target_elf_flavour) return FALSE; switch (h->root.type) { default: abfd = NULL; break; case bfd_link_hash_undefined: case bfd_link_hash_undefweak: abfd = h->root.u.undef.abfd; if ((abfd->flags & DYNAMIC) == 0 || elf_dt_soname (abfd) == NULL) return FALSE; break; case bfd_link_hash_defined: case bfd_link_hash_defweak: abfd = h->root.u.def.section->owner; break; case bfd_link_hash_common: abfd = h->root.u.c.p->section->owner; break; } BFD_ASSERT (abfd != NULL); for (loaded = elf_hash_table (info)->loaded; loaded != NULL; loaded = loaded->next) { bfd *input; Elf_Internal_Shdr *hdr; bfd_size_type symcount; bfd_size_type extsymcount; bfd_size_type extsymoff; Elf_Internal_Shdr *versymhdr; Elf_Internal_Sym *isym; Elf_Internal_Sym *isymend; Elf_Internal_Sym *isymbuf; Elf_External_Versym *ever; Elf_External_Versym *extversym; input = loaded->abfd; /* We check each DSO for a possible hidden versioned definition. */ if (input == abfd || (input->flags & DYNAMIC) == 0 || elf_dynversym (input) == 0) continue; hdr = &elf_tdata (input)->dynsymtab_hdr; symcount = hdr->sh_size / sizeof (Elf_External_Sym); if (elf_bad_symtab (input)) { extsymcount = symcount; extsymoff = 0; } else { extsymcount = symcount - hdr->sh_info; extsymoff = hdr->sh_info; } if (extsymcount == 0) continue; isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff, NULL, NULL, NULL); if (isymbuf == NULL) return FALSE; /* Read in any version definitions. */ versymhdr = &elf_tdata (input)->dynversym_hdr; extversym = (Elf_External_Versym *) bfd_malloc (versymhdr->sh_size); if (extversym == NULL) goto error_ret; if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0 || (bfd_bread ((PTR) extversym, versymhdr->sh_size, input) != versymhdr->sh_size)) { free (extversym); error_ret: free (isymbuf); return FALSE; } ever = extversym + extsymoff; isymend = isymbuf + extsymcount; for (isym = isymbuf; isym < isymend; isym++, ever++) { const char *name; Elf_Internal_Versym iver; unsigned short version_index; if (ELF_ST_BIND (isym->st_info) == STB_LOCAL || isym->st_shndx == SHN_UNDEF) continue; name = bfd_elf_string_from_elf_section (input, hdr->sh_link, isym->st_name); if (strcmp (name, h->root.root.string) != 0) continue; _bfd_elf_swap_versym_in (input, ever, &iver); if ((iver.vs_vers & VERSYM_HIDDEN) == 0) { /* If we have a non-hidden versioned sym, then it should have provided a definition for the undefined sym. */ abort (); } version_index = iver.vs_vers & VERSYM_VERSION; if (version_index == 1 || version_index == 2) { /* This is the base or first version. We can use it. */ free (extversym); free (isymbuf); return TRUE; } } free (extversym); free (isymbuf); } return FALSE; } /* Add an external symbol to the symbol table. This is called from the hash table traversal routine. When generating a shared object, we go through the symbol table twice. The first time we output anything that might have been forced to local scope in a version script. The second time we output the symbols that are still global symbols. */ static bfd_boolean elf_link_output_extsym (h, data) struct elf_link_hash_entry *h; PTR data; { struct elf_outext_info *eoinfo = (struct elf_outext_info *) data; struct elf_final_link_info *finfo = eoinfo->finfo; bfd_boolean strip; Elf_Internal_Sym sym; asection *input_sec; if (h->root.type == bfd_link_hash_warning) { h = (struct elf_link_hash_entry *) h->root.u.i.link; if (h->root.type == bfd_link_hash_new) return TRUE; } /* Decide whether to output this symbol in this pass. */ if (eoinfo->localsyms) { if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) return TRUE; } else { if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0) return TRUE; } /* If we are not creating a shared library, and this symbol is referenced by a shared library but is not defined anywhere, then warn that it is undefined. If we do not do this, the runtime linker will complain that the symbol is undefined when the program is run. We don't have to worry about symbols that are referenced by regular files, because we will already have issued warnings for them. */ if (! finfo->info->relocateable && (finfo->info->executable || ! finfo->info->allow_shlib_undefined) && h->root.type == bfd_link_hash_undefined && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0 && ! elf_link_check_versioned_symbol (finfo->info, h)) { if (! ((*finfo->info->callbacks->undefined_symbol) (finfo->info, h->root.root.string, h->root.u.undef.abfd, (asection *) NULL, (bfd_vma) 0, TRUE))) { eoinfo->failed = TRUE; return FALSE; } } /* We should also warn if a forced local symbol is referenced from shared libraries. */ if (! finfo->info->relocateable && (! finfo->info->shared || ! finfo->info->allow_shlib_undefined) && (h->elf_link_hash_flags & (ELF_LINK_FORCED_LOCAL | ELF_LINK_HASH_REF_DYNAMIC | ELF_LINK_DYNAMIC_DEF | ELF_LINK_DYNAMIC_WEAK)) == (ELF_LINK_FORCED_LOCAL | ELF_LINK_HASH_REF_DYNAMIC) && ! elf_link_check_versioned_symbol (finfo->info, h)) { (*_bfd_error_handler) (_("%s: %s symbol `%s' in %s is referenced by DSO"), bfd_get_filename (finfo->output_bfd), ELF_ST_VISIBILITY (h->other) == STV_INTERNAL ? "internal" : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN ? "hidden" : "local", h->root.root.string, bfd_archive_filename (h->root.u.def.section->owner)); eoinfo->failed = TRUE; return FALSE; } /* We don't want to output symbols that have never been mentioned by a regular file, or that we have been told to strip. However, if h->indx is set to -2, the symbol is used by a reloc and we must output it. */ if (h->indx == -2) strip = FALSE; else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0) && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0) strip = TRUE; else if (finfo->info->strip == strip_all) strip = TRUE; else if (finfo->info->strip == strip_some && bfd_hash_lookup (finfo->info->keep_hash, h->root.root.string, FALSE, FALSE) == NULL) strip = TRUE; else if (finfo->info->strip_discarded && (h->root.type == bfd_link_hash_defined || h->root.type == bfd_link_hash_defweak) && elf_discarded_section (h->root.u.def.section)) strip = TRUE; else 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. */ if (strip && h->dynindx == -1 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) return TRUE; sym.st_value = 0; sym.st_size = h->size; sym.st_other = h->other; if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0) sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type); else if (h->root.type == bfd_link_hash_undefweak || h->root.type == bfd_link_hash_defweak) sym.st_info = ELF_ST_INFO (STB_WEAK, h->type); else sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type); switch (h->root.type) { default: case bfd_link_hash_new: case bfd_link_hash_warning: abort (); return FALSE; case bfd_link_hash_undefined: case bfd_link_hash_undefweak: input_sec = bfd_und_section_ptr; sym.st_shndx = SHN_UNDEF; break; case bfd_link_hash_defined: case bfd_link_hash_defweak: { input_sec = h->root.u.def.section; if (input_sec->output_section != NULL) { sym.st_shndx = _bfd_elf_section_from_bfd_section (finfo->output_bfd, input_sec->output_section); if (sym.st_shndx == SHN_BAD) { (*_bfd_error_handler) (_("%s: could not find output section %s for input section %s"), bfd_get_filename (finfo->output_bfd), input_sec->output_section->name, input_sec->name); eoinfo->failed = TRUE; return FALSE; } /* ELF symbols in relocateable files are section relative, but in nonrelocateable files they are virtual addresses. */ sym.st_value = h->root.u.def.value + input_sec->output_offset; if (! finfo->info->relocateable) { sym.st_value += input_sec->output_section->vma; if (h->type == STT_TLS) { /* STT_TLS symbols are relative to PT_TLS segment base. */ BFD_ASSERT (finfo->first_tls_sec != NULL); sym.st_value -= finfo->first_tls_sec->vma; } } } else { BFD_ASSERT (input_sec->owner == NULL || (input_sec->owner->flags & DYNAMIC) != 0); sym.st_shndx = SHN_UNDEF; input_sec = bfd_und_section_ptr; } } break; case bfd_link_hash_common: input_sec = h->root.u.c.p->section; sym.st_shndx = SHN_COMMON; sym.st_value = 1 << h->root.u.c.p->alignment_power; break; case bfd_link_hash_indirect: /* These symbols are created by symbol versioning. They point to the decorated version of the name. For example, if the symbol foo@@GNU_1.2 is the default, which should be used when foo is used with no version, then we add an indirect symbol foo which points to foo@@GNU_1.2. We ignore these symbols, since the indirected symbol is already in the hash table. */ return TRUE; } /* Give the processor backend a chance to tweak the symbol value, and also to finish up anything that needs to be done for this symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for forced local syms when non-shared is due to a historical quirk. */ if ((h->dynindx != -1 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0) && ((finfo->info->shared && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT || h->root.type != bfd_link_hash_undefweak)) || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) && elf_hash_table (finfo->info)->dynamic_sections_created) { struct elf_backend_data *bed; bed = get_elf_backend_data (finfo->output_bfd); if (! ((*bed->elf_backend_finish_dynamic_symbol) (finfo->output_bfd, finfo->info, h, &sym))) { eoinfo->failed = TRUE; return FALSE; } } /* If we are marking the symbol as undefined, and there are no non-weak references to this symbol from a regular object, then mark the symbol as weak undefined; if there are non-weak references, mark the symbol as strong. We can't do this earlier, because it might not be marked as undefined until the finish_dynamic_symbol routine gets through with it. */ if (sym.st_shndx == SHN_UNDEF && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL || ELF_ST_BIND (sym.st_info) == STB_WEAK)) { int bindtype; if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0) bindtype = STB_GLOBAL; else bindtype = STB_WEAK; sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info)); } /* If a non-weak symbol with non-default visibility is not defined locally, it is a fatal error. */ if (! finfo->info->relocateable && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT && ELF_ST_BIND (sym.st_info) != STB_WEAK && h->root.type == bfd_link_hash_undefined && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0) { (*_bfd_error_handler) (_("%s: %s symbol `%s' isn't defined"), bfd_get_filename (finfo->output_bfd), ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED ? "protected" : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL ? "internal" : "hidden", h->root.root.string); eoinfo->failed = TRUE; return FALSE; } /* If this symbol should be put in the .dynsym section, then put it there now. We already know the symbol index. We also fill in the entry in the .hash section. */ if (h->dynindx != -1 && elf_hash_table (finfo->info)->dynamic_sections_created) { size_t bucketcount; size_t bucket; size_t hash_entry_size; bfd_byte *bucketpos; bfd_vma chain; Elf_External_Sym *esym; sym.st_name = h->dynstr_index; esym = (Elf_External_Sym *) finfo->dynsym_sec->contents + h->dynindx; elf_swap_symbol_out (finfo->output_bfd, &sym, (PTR) esym, (PTR) 0); bucketcount = elf_hash_table (finfo->info)->bucketcount; bucket = h->elf_hash_value % bucketcount; hash_entry_size = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize; bucketpos = ((bfd_byte *) finfo->hash_sec->contents + (bucket + 2) * hash_entry_size); chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos); bfd_put (8 * hash_entry_size, finfo->output_bfd, (bfd_vma) h->dynindx, bucketpos); bfd_put (8 * hash_entry_size, finfo->output_bfd, chain, ((bfd_byte *) finfo->hash_sec->contents + (bucketcount + 2 + h->dynindx) * hash_entry_size)); if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL) { Elf_Internal_Versym iversym; Elf_External_Versym *eversym; if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0) { if (h->verinfo.verdef == NULL) iversym.vs_vers = 0; else iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1; } else { if (h->verinfo.vertree == NULL) iversym.vs_vers = 1; else iversym.vs_vers = h->verinfo.vertree->vernum + 1; } if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0) iversym.vs_vers |= VERSYM_HIDDEN; eversym = (Elf_External_Versym *) finfo->symver_sec->contents; eversym += h->dynindx; _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym); } } /* If we're stripping it, then it was just a dynamic symbol, and there's nothing else to do. */ if (strip || (input_sec->flags & SEC_EXCLUDE) != 0) return TRUE; h->indx = bfd_get_symcount (finfo->output_bfd); if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec)) { eoinfo->failed = TRUE; return FALSE; } return TRUE; } /* Link an input file into the linker output file. This function handles all the sections and relocations of the input file at once. This is so that we only have to read the local symbols once, and don't have to keep them in memory. */ static bfd_boolean elf_link_input_bfd (finfo, input_bfd) struct elf_final_link_info *finfo; bfd *input_bfd; { bfd_boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *, Elf_Internal_Rela *, Elf_Internal_Sym *, asection **)); bfd *output_bfd; Elf_Internal_Shdr *symtab_hdr; size_t locsymcount; size_t extsymoff; Elf_Internal_Sym *isymbuf; Elf_Internal_Sym *isym; Elf_Internal_Sym *isymend; long *pindex; asection **ppsection; asection *o; struct elf_backend_data *bed; bfd_boolean emit_relocs; struct elf_link_hash_entry **sym_hashes; output_bfd = finfo->output_bfd; bed = get_elf_backend_data (output_bfd); relocate_section = bed->elf_backend_relocate_section; /* If this is a dynamic object, we don't want to do anything here: we don't want the local symbols, and we don't want the section contents. */ if ((input_bfd->flags & DYNAMIC) != 0) return TRUE; emit_relocs = (finfo->info->relocateable || finfo->info->emitrelocations || bed->elf_backend_emit_relocs); symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; if (elf_bad_symtab (input_bfd)) { locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym); extsymoff = 0; } else { locsymcount = symtab_hdr->sh_info; extsymoff = symtab_hdr->sh_info; } /* Read the local symbols. */ isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents; if (isymbuf == NULL && locsymcount != 0) { isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0, finfo->internal_syms, finfo->external_syms, finfo->locsym_shndx); if (isymbuf == NULL) return FALSE; } /* Find local symbol sections and adjust values of symbols in SEC_MERGE sections. Write out those local symbols we know are going into the output file. */ isymend = isymbuf + locsymcount; for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections; isym < isymend; isym++, pindex++, ppsection++) { asection *isec; const char *name; Elf_Internal_Sym osym; *pindex = -1; if (elf_bad_symtab (input_bfd)) { if (ELF_ST_BIND (isym->st_info) != STB_LOCAL) { *ppsection = NULL; continue; } } if (isym->st_shndx == SHN_UNDEF) isec = bfd_und_section_ptr; else if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE) { isec = section_from_elf_index (input_bfd, isym->st_shndx); if (isec && isec->sec_info_type == ELF_INFO_TYPE_MERGE && ELF_ST_TYPE (isym->st_info) != STT_SECTION) isym->st_value = _bfd_merged_section_offset (output_bfd, &isec, elf_section_data (isec)->sec_info, isym->st_value, (bfd_vma) 0); } else if (isym->st_shndx == SHN_ABS) isec = bfd_abs_section_ptr; else if (isym->st_shndx == SHN_COMMON) isec = bfd_com_section_ptr; else { /* Who knows? */ isec = NULL; } *ppsection = isec; /* Don't output the first, undefined, symbol. */ if (ppsection == finfo->sections) continue; if (ELF_ST_TYPE (isym->st_info) == STT_SECTION) { /* We never output section symbols. Instead, we use the section symbol of the corresponding section in the output file. */ continue; } /* If we are stripping all symbols, we don't want to output this one. */ if (finfo->info->strip == strip_all) continue; /* If we are discarding all local symbols, we don't want to output this one. If we are generating a relocateable output file, then some of the local symbols may be required by relocs; we output them below as we discover that they are needed. */ if (finfo->info->discard == discard_all) continue; /* If this symbol is defined in a section which we are discarding, we don't need to keep it, but note that linker_mark is only reliable for sections that have contents. For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE as well as linker_mark. */ if ((isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE) && isec != NULL && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0) || (! finfo->info->relocateable && (isec->flags & SEC_EXCLUDE) != 0))) continue; /* Get the name of the symbol. */ name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link, isym->st_name); if (name == NULL) return FALSE; /* See if we are discarding symbols with this name. */ if ((finfo->info->strip == strip_some && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE) == NULL)) || (((finfo->info->discard == discard_sec_merge && (isec->flags & SEC_MERGE) && ! finfo->info->relocateable) || finfo->info->discard == discard_l) && bfd_is_local_label_name (input_bfd, name))) continue; /* If we get here, we are going to output this symbol. */ osym = *isym; /* Adjust the section index for the output file. */ osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd, isec->output_section); if (osym.st_shndx == SHN_BAD) return FALSE; *pindex = bfd_get_symcount (output_bfd); /* ELF symbols in relocateable files are section relative, but in executable files they are virtual addresses. Note that this code assumes that all ELF sections have an associated BFD section with a reasonable value for output_offset; below we assume that they also have a reasonable value for output_section. Any special sections must be set up to meet these requirements. */ osym.st_value += isec->output_offset; if (! finfo->info->relocateable) { osym.st_value += isec->output_section->vma; if (ELF_ST_TYPE (osym.st_info) == STT_TLS) { /* STT_TLS symbols are relative to PT_TLS segment base. */ BFD_ASSERT (finfo->first_tls_sec != NULL); osym.st_value -= finfo->first_tls_sec->vma; } } if (! elf_link_output_sym (finfo, name, &osym, isec)) return FALSE; } /* Relocate the contents of each section. */ sym_hashes = elf_sym_hashes (input_bfd); for (o = input_bfd->sections; o != NULL; o = o->next) { bfd_byte *contents; if (! o->linker_mark) { /* This section was omitted from the link. */ continue; } if ((o->flags & SEC_HAS_CONTENTS) == 0 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0)) continue; if ((o->flags & SEC_LINKER_CREATED) != 0) { /* Section was created by _bfd_elf_link_create_dynamic_sections or somesuch. */ continue; } /* Get the contents of the section. They have been cached by a relaxation routine. Note that o is a section in an input file, so the contents field will not have been set by any of the routines which work on output files. */ if (elf_section_data (o)->this_hdr.contents != NULL) contents = elf_section_data (o)->this_hdr.contents; else { contents = finfo->contents; if (! bfd_get_section_contents (input_bfd, o, contents, (file_ptr) 0, o->_raw_size)) return FALSE; } if ((o->flags & SEC_RELOC) != 0) { Elf_Internal_Rela *internal_relocs; /* Get the swapped relocs. */ internal_relocs = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs, finfo->internal_relocs, FALSE); if (internal_relocs == NULL && o->reloc_count > 0) return FALSE; /* Run through the relocs looking for any against symbols from discarded sections and section symbols from removed link-once sections. Complain about relocs against discarded sections. Zero relocs against removed link-once sections. */ if (!finfo->info->relocateable && !elf_section_ignore_discarded_relocs (o)) { Elf_Internal_Rela *rel, *relend; rel = internal_relocs; relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel; for ( ; rel < relend; rel++) { unsigned long r_symndx = ELF_R_SYM (rel->r_info); if (r_symndx >= locsymcount || (elf_bad_symtab (input_bfd) && finfo->sections[r_symndx] == NULL)) { struct elf_link_hash_entry *h; h = sym_hashes[r_symndx - extsymoff]; 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; /* Complain if the definition comes from a discarded section. */ if ((h->root.type == bfd_link_hash_defined || h->root.type == bfd_link_hash_defweak) && elf_discarded_section (h->root.u.def.section)) { if ((o->flags & SEC_DEBUGGING) != 0) { BFD_ASSERT (r_symndx != 0); memset (rel, 0, sizeof (*rel)); } else finfo->info->callbacks->error_handler (LD_DEFINITION_IN_DISCARDED_SECTION, _("%T: discarded in section `%s' from %s\n"), h->root.root.string, h->root.root.string, h->root.u.def.section->name, bfd_archive_filename (h->root.u.def.section->owner)); } } else { asection *sec = finfo->sections[r_symndx]; if (sec != NULL && elf_discarded_section (sec)) { if ((o->flags & SEC_DEBUGGING) != 0 || (sec->flags & SEC_LINK_ONCE) != 0) { BFD_ASSERT (r_symndx != 0); rel->r_info = ELF_R_INFO (0, ELF_R_TYPE (rel->r_info)); rel->r_addend = 0; } else { static int count; int ok; char *buf; ok = asprintf (&buf, "local symbol %d", count++); if (ok <= 0) buf = (char *) "local symbol"; finfo->info->callbacks->error_handler (LD_DEFINITION_IN_DISCARDED_SECTION, _("%T: discarded in section `%s' from %s\n"), buf, buf, sec->name, bfd_archive_filename (input_bfd)); if (ok != -1) free (buf); } } } } } /* Relocate the section by invoking a back end routine. The back end routine is responsible for adjusting the section contents as necessary, and (if using Rela relocs and generating a relocateable output file) adjusting the reloc addend as necessary. The back end routine does not have to worry about setting the reloc address or the reloc symbol index. The back end routine is given a pointer to the swapped in internal symbols, and can access the hash table entries for the external symbols via elf_sym_hashes (input_bfd). When generating relocateable output, the back end routine must handle STB_LOCAL/STT_SECTION symbols specially. The output symbol is going to be a section symbol corresponding to the output section, which will require the addend to be adjusted. */ if (! (*relocate_section) (output_bfd, finfo->info, input_bfd, o, contents, internal_relocs, isymbuf, finfo->sections)) return FALSE; if (emit_relocs) { Elf_Internal_Rela *irela; Elf_Internal_Rela *irelaend; bfd_vma last_offset; struct elf_link_hash_entry **rel_hash; Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2; unsigned int next_erel; bfd_boolean (*reloc_emitter) PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *)); bfd_boolean rela_normal; input_rel_hdr = &elf_section_data (o)->rel_hdr; rela_normal = (bed->rela_normal && (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rela))); /* Adjust the reloc addresses and symbol indices. */ irela = internal_relocs; irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel; rel_hash = (elf_section_data (o->output_section)->rel_hashes + elf_section_data (o->output_section)->rel_count + elf_section_data (o->output_section)->rel_count2); last_offset = o->output_offset; if (!finfo->info->relocateable) last_offset += o->output_section->vma; for (next_erel = 0; irela < irelaend; irela++, next_erel++) { unsigned long r_symndx; asection *sec; Elf_Internal_Sym sym; if (next_erel == bed->s->int_rels_per_ext_rel) { rel_hash++; next_erel = 0; } irela->r_offset = _bfd_elf_section_offset (output_bfd, finfo->info, o, irela->r_offset); if (irela->r_offset >= (bfd_vma) -2) { /* This is a reloc for a deleted entry or somesuch. Turn it into an R_*_NONE reloc, at the same offset as the last reloc. elf_eh_frame.c and elf_bfd_discard_info rely on reloc offsets being ordered. */ irela->r_offset = last_offset; irela->r_info = 0; irela->r_addend = 0; continue; } irela->r_offset += o->output_offset; /* Relocs in an executable have to be virtual addresses. */ if (!finfo->info->relocateable) irela->r_offset += o->output_section->vma; last_offset = irela->r_offset; r_symndx = ELF_R_SYM (irela->r_info); if (r_symndx == STN_UNDEF) continue; if (r_symndx >= locsymcount || (elf_bad_symtab (input_bfd) && finfo->sections[r_symndx] == NULL)) { struct elf_link_hash_entry *rh; unsigned long indx; /* This is a reloc against a global symbol. We have not yet output all the local symbols, so we do not know the symbol index of any global symbol. We set the rel_hash entry for this reloc to point to the global hash table entry for this symbol. The symbol index is then set at the end of elf_bfd_final_link. */ indx = r_symndx - extsymoff; rh = elf_sym_hashes (input_bfd)[indx]; while (rh->root.type == bfd_link_hash_indirect || rh->root.type == bfd_link_hash_warning) rh = (struct elf_link_hash_entry *) rh->root.u.i.link; /* Setting the index to -2 tells elf_link_output_extsym that this symbol is used by a reloc. */ BFD_ASSERT (rh->indx < 0); rh->indx = -2; *rel_hash = rh; continue; } /* This is a reloc against a local symbol. */ *rel_hash = NULL; sym = isymbuf[r_symndx]; sec = finfo->sections[r_symndx]; if (ELF_ST_TYPE (sym.st_info) == STT_SECTION) { /* I suppose the backend ought to fill in the section of any STT_SECTION symbol against a processor specific section. If we have discarded a section, the output_section will be the absolute section. */ if (bfd_is_abs_section (sec) || (sec != NULL && bfd_is_abs_section (sec->output_section))) r_symndx = 0; else if (sec == NULL || sec->owner == NULL) { bfd_set_error (bfd_error_bad_value); return FALSE; } else { r_symndx = sec->output_section->target_index; BFD_ASSERT (r_symndx != 0); } /* Adjust the addend according to where the section winds up in the output section. */ if (rela_normal) irela->r_addend += sec->output_offset; } else { if (finfo->indices[r_symndx] == -1) { unsigned long shlink; const char *name; asection *osec; if (finfo->info->strip == strip_all) { /* You can't do ld -r -s. */ bfd_set_error (bfd_error_invalid_operation); return FALSE; } /* This symbol was skipped earlier, but since it is needed by a reloc, we must output it now. */ shlink = symtab_hdr->sh_link; name = (bfd_elf_string_from_elf_section (input_bfd, shlink, sym.st_name)); if (name == NULL) return FALSE; osec = sec->output_section; sym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd, osec); if (sym.st_shndx == SHN_BAD) return FALSE; sym.st_value += sec->output_offset; if (! finfo->info->relocateable) { sym.st_value += osec->vma; if (ELF_ST_TYPE (sym.st_info) == STT_TLS) { /* STT_TLS symbols are relative to PT_TLS segment base. */ BFD_ASSERT (finfo->first_tls_sec != NULL); sym.st_value -= finfo->first_tls_sec->vma; } } finfo->indices[r_symndx] = bfd_get_symcount (output_bfd); if (! elf_link_output_sym (finfo, name, &sym, sec)) return FALSE; } r_symndx = finfo->indices[r_symndx]; } irela->r_info = ELF_R_INFO (r_symndx, ELF_R_TYPE (irela->r_info)); } /* Swap out the relocs. */ if (bed->elf_backend_emit_relocs && !(finfo->info->relocateable || finfo->info->emitrelocations)) reloc_emitter = bed->elf_backend_emit_relocs; else reloc_emitter = _bfd_elf_link_output_relocs; if (input_rel_hdr->sh_size != 0 && ! (*reloc_emitter) (output_bfd, o, input_rel_hdr, internal_relocs)) return FALSE; input_rel_hdr2 = elf_section_data (o)->rel_hdr2; if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0) { internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr) * bed->s->int_rels_per_ext_rel); if (! (*reloc_emitter) (output_bfd, o, input_rel_hdr2, internal_relocs)) return FALSE; } } } /* Write out the modified section contents. */ if (bed->elf_backend_write_section && (*bed->elf_backend_write_section) (output_bfd, o, contents)) { /* Section written out. */ } else switch (o->sec_info_type) { case ELF_INFO_TYPE_STABS: if (! (_bfd_write_section_stabs (output_bfd, &elf_hash_table (finfo->info)->stab_info, o, &elf_section_data (o)->sec_info, contents))) return FALSE; break; case ELF_INFO_TYPE_MERGE: if (! _bfd_write_merged_section (output_bfd, o, elf_section_data (o)->sec_info)) return FALSE; break; case ELF_INFO_TYPE_EH_FRAME: { if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info, o, contents)) return FALSE; } break; default: { bfd_size_type sec_size; sec_size = (o->_cooked_size != 0 ? o->_cooked_size : o->_raw_size); if (! (o->flags & SEC_EXCLUDE) && ! bfd_set_section_contents (output_bfd, o->output_section, contents, (file_ptr) o->output_offset, sec_size)) return FALSE; } break; } } return TRUE; } /* Generate a reloc when linking an ELF file. This is a reloc requested by the linker, and does come from any input file. This is used to build constructor and destructor tables when linking with -Ur. */ static bfd_boolean elf_reloc_link_order (output_bfd, info, output_section, link_order) bfd *output_bfd; struct bfd_link_info *info; asection *output_section; struct bfd_link_order *link_order; { reloc_howto_type *howto; long indx; bfd_vma offset; bfd_vma addend; struct elf_link_hash_entry **rel_hash_ptr; Elf_Internal_Shdr *rel_hdr; struct elf_backend_data *bed = get_elf_backend_data (output_bfd); Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL]; bfd_byte *erel; unsigned int i; howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc); if (howto == NULL) { bfd_set_error (bfd_error_bad_value); return FALSE; } addend = link_order->u.reloc.p->addend; /* Figure out the symbol index. */ rel_hash_ptr = (elf_section_data (output_section)->rel_hashes + elf_section_data (output_section)->rel_count + elf_section_data (output_section)->rel_count2); if (link_order->type == bfd_section_reloc_link_order) { indx = link_order->u.reloc.p->u.section->target_index; BFD_ASSERT (indx != 0); *rel_hash_ptr = NULL; } else { struct elf_link_hash_entry *h; /* Treat a reloc against a defined symbol as though it were actually against the section. */ h = ((struct elf_link_hash_entry *) bfd_wrapped_link_hash_lookup (output_bfd, info, link_order->u.reloc.p->u.name, FALSE, FALSE, TRUE)); if (h != NULL && (h->root.type == bfd_link_hash_defined || h->root.type == bfd_link_hash_defweak)) { asection *section; section = h->root.u.def.section; indx = section->output_section->target_index; *rel_hash_ptr = NULL; /* It seems that we ought to add the symbol value to the addend here, but in practice it has already been added because it was passed to constructor_callback. */ addend += section->output_section->vma + section->output_offset; } else if (h != NULL) { /* Setting the index to -2 tells elf_link_output_extsym that this symbol is used by a reloc. */ h->indx = -2; *rel_hash_ptr = h; indx = 0; } else { if (! ((*info->callbacks->unattached_reloc) (info, link_order->u.reloc.p->u.name, (bfd *) NULL, (asection *) NULL, (bfd_vma) 0))) return FALSE; indx = 0; } } /* If this is an inplace reloc, we must write the addend into the object file. */ if (howto->partial_inplace && addend != 0) { bfd_size_type size; bfd_reloc_status_type rstat; bfd_byte *buf; bfd_boolean ok; const char *sym_name; size = bfd_get_reloc_size (howto); buf = (bfd_byte *) bfd_zmalloc (size); if (buf == (bfd_byte *) NULL) return FALSE; rstat = _bfd_relocate_contents (howto, output_bfd, (bfd_vma) addend, buf); switch (rstat) { case bfd_reloc_ok: break; default: case bfd_reloc_outofrange: abort (); case bfd_reloc_overflow: if (link_order->type == bfd_section_reloc_link_order) sym_name = bfd_section_name (output_bfd, link_order->u.reloc.p->u.section); else sym_name = link_order->u.reloc.p->u.name; if (! ((*info->callbacks->reloc_overflow) (info, sym_name, howto->name, addend, (bfd *) NULL, (asection *) NULL, (bfd_vma) 0))) { free (buf); return FALSE; } break; } ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf, (file_ptr) link_order->offset, size); free (buf); if (! ok) return FALSE; } /* The address of a reloc is relative to the section in a relocateable file, and is a virtual address in an executable file. */ offset = link_order->offset; if (! info->relocateable) offset += output_section->vma; for (i = 0; i < bed->s->int_rels_per_ext_rel; i++) { irel[i].r_offset = offset; irel[i].r_info = 0; irel[i].r_addend = 0; } irel[0].r_info = ELF_R_INFO (indx, howto->type); rel_hdr = &elf_section_data (output_section)->rel_hdr; erel = rel_hdr->contents; if (rel_hdr->sh_type == SHT_REL) { erel += (elf_section_data (output_section)->rel_count * sizeof (Elf_External_Rel)); (*bed->s->swap_reloc_out) (output_bfd, irel, erel); } else { irel[0].r_addend = addend; erel += (elf_section_data (output_section)->rel_count * sizeof (Elf_External_Rela)); (*bed->s->swap_reloca_out) (output_bfd, irel, erel); } ++elf_section_data (output_section)->rel_count; return TRUE; } /* Allocate a pointer to live in a linker created section. */ bfd_boolean elf_create_pointer_linker_section (abfd, info, lsect, h, rel) bfd *abfd; struct bfd_link_info *info; elf_linker_section_t *lsect; struct elf_link_hash_entry *h; const Elf_Internal_Rela *rel; { elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL; elf_linker_section_pointers_t *linker_section_ptr; unsigned long r_symndx = ELF_R_SYM (rel->r_info); bfd_size_type amt; BFD_ASSERT (lsect != NULL); /* Is this a global symbol? */ if (h != NULL) { /* Has this symbol already been allocated? If so, our work is done. */ if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer, rel->r_addend, lsect->which)) return TRUE; ptr_linker_section_ptr = &h->linker_section_pointer; /* Make sure this symbol is output as a dynamic symbol. */ if (h->dynindx == -1) { if (! elf_link_record_dynamic_symbol (info, h)) return FALSE; } if (lsect->rel_section) lsect->rel_section->_raw_size += sizeof (Elf_External_Rela); } else { /* Allocation of a pointer to a local symbol. */ elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd); /* Allocate a table to hold the local symbols if first time. */ if (!ptr) { unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info; register unsigned int i; amt = num_symbols; amt *= sizeof (elf_linker_section_pointers_t *); ptr = (elf_linker_section_pointers_t **) bfd_alloc (abfd, amt); if (!ptr) return FALSE; elf_local_ptr_offsets (abfd) = ptr; for (i = 0; i < num_symbols; i++) ptr[i] = (elf_linker_section_pointers_t *) 0; } /* Has this symbol already been allocated? If so, our work is done. */ if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx], rel->r_addend, lsect->which)) return TRUE; ptr_linker_section_ptr = &ptr[r_symndx]; if (info->shared) { /* If we are generating a shared object, we need to output a R__RELATIVE reloc so that the dynamic linker can adjust this GOT entry. */ BFD_ASSERT (lsect->rel_section != NULL); lsect->rel_section->_raw_size += sizeof (Elf_External_Rela); } } /* Allocate space for a pointer in the linker section, and allocate a new pointer record from internal memory. */ BFD_ASSERT (ptr_linker_section_ptr != NULL); amt = sizeof (elf_linker_section_pointers_t); linker_section_ptr = (elf_linker_section_pointers_t *) bfd_alloc (abfd, amt); if (!linker_section_ptr) return FALSE; linker_section_ptr->next = *ptr_linker_section_ptr; linker_section_ptr->addend = rel->r_addend; linker_section_ptr->which = lsect->which; linker_section_ptr->written_address_p = FALSE; *ptr_linker_section_ptr = linker_section_ptr; #if 0 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset) { linker_section_ptr->offset = (lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8)); lsect->hole_offset += ARCH_SIZE / 8; lsect->sym_offset += ARCH_SIZE / 8; if (lsect->sym_hash) { /* Bump up symbol value if needed. */ lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8; #ifdef DEBUG fprintf (stderr, "Bump up %s by %ld, current value = %ld\n", lsect->sym_hash->root.root.string, (long) ARCH_SIZE / 8, (long) lsect->sym_hash->root.u.def.value); #endif } } else #endif linker_section_ptr->offset = lsect->section->_raw_size; lsect->section->_raw_size += ARCH_SIZE / 8; #ifdef DEBUG fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n", lsect->name, (long) linker_section_ptr->offset, (long) lsect->section->_raw_size); #endif return TRUE; } #if ARCH_SIZE==64 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR) #endif #if ARCH_SIZE==32 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR) #endif /* Fill in the address for a pointer generated in a linker section. */ bfd_vma elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc) bfd *output_bfd; bfd *input_bfd; struct bfd_link_info *info; elf_linker_section_t *lsect; struct elf_link_hash_entry *h; bfd_vma relocation; const Elf_Internal_Rela *rel; int relative_reloc; { elf_linker_section_pointers_t *linker_section_ptr; BFD_ASSERT (lsect != NULL); if (h != NULL) { /* Handle global symbol. */ linker_section_ptr = (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer, rel->r_addend, lsect->which)); BFD_ASSERT (linker_section_ptr != NULL); if (! elf_hash_table (info)->dynamic_sections_created || (info->shared && info->symbolic && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))) { /* This is actually a static link, or it is a -Bsymbolic link and the symbol is defined locally. We must initialize this entry in the global section. When doing a dynamic link, we create a .rela. relocation entry to initialize the value. This is done in the finish_dynamic_symbol routine. */ if (!linker_section_ptr->written_address_p) { linker_section_ptr->written_address_p = TRUE; bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend, (lsect->section->contents + linker_section_ptr->offset)); } } } else { /* Handle local symbol. */ unsigned long r_symndx = ELF_R_SYM (rel->r_info); BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL); BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL); linker_section_ptr = (_bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx], rel->r_addend, lsect->which)); BFD_ASSERT (linker_section_ptr != NULL); /* Write out pointer if it hasn't been rewritten out before. */ if (!linker_section_ptr->written_address_p) { linker_section_ptr->written_address_p = TRUE; bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend, lsect->section->contents + linker_section_ptr->offset); if (info->shared) { asection *srel = lsect->rel_section; Elf_Internal_Rela outrel[MAX_INT_RELS_PER_EXT_REL]; bfd_byte *erel; struct elf_backend_data *bed = get_elf_backend_data (output_bfd); unsigned int i; /* We need to generate a relative reloc for the dynamic linker. */ if (!srel) { srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj, lsect->rel_name); lsect->rel_section = srel; } BFD_ASSERT (srel != NULL); for (i = 0; i < bed->s->int_rels_per_ext_rel; i++) { outrel[i].r_offset = (lsect->section->output_section->vma + lsect->section->output_offset + linker_section_ptr->offset); outrel[i].r_info = 0; outrel[i].r_addend = 0; } outrel[0].r_info = ELF_R_INFO (0, relative_reloc); erel = lsect->section->contents; erel += (elf_section_data (lsect->section)->rel_count++ * sizeof (Elf_External_Rela)); elf_swap_reloca_out (output_bfd, outrel, erel); } } } relocation = (lsect->section->output_offset + linker_section_ptr->offset - lsect->hole_offset - lsect->sym_offset); #ifdef DEBUG fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n", lsect->name, (long) relocation, (long) relocation); #endif /* Subtract out the addend, because it will get added back in by the normal processing. */ return relocation - linker_section_ptr->addend; } /* Garbage collect unused sections. */ static bfd_boolean elf_gc_mark PARAMS ((struct bfd_link_info *, asection *, asection * (*) (asection *, struct bfd_link_info *, Elf_Internal_Rela *, struct elf_link_hash_entry *, Elf_Internal_Sym *))); static bfd_boolean elf_gc_sweep PARAMS ((struct bfd_link_info *, bfd_boolean (*) (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *))); static bfd_boolean elf_gc_sweep_symbol PARAMS ((struct elf_link_hash_entry *, PTR)); static bfd_boolean elf_gc_allocate_got_offsets PARAMS ((struct elf_link_hash_entry *, PTR)); static bfd_boolean elf_gc_propagate_vtable_entries_used PARAMS ((struct elf_link_hash_entry *, PTR)); static bfd_boolean elf_gc_smash_unused_vtentry_relocs PARAMS ((struct elf_link_hash_entry *, PTR)); /* The mark phase of garbage collection. For a given section, mark it and any sections in this section's group, and all the sections which define symbols to which it refers. */ typedef asection * (*gc_mark_hook_fn) PARAMS ((asection *, struct bfd_link_info *, Elf_Internal_Rela *, struct elf_link_hash_entry *, Elf_Internal_Sym *)); static bfd_boolean elf_gc_mark (info, sec, gc_mark_hook) struct bfd_link_info *info; asection *sec; gc_mark_hook_fn gc_mark_hook; { bfd_boolean ret; asection *group_sec; sec->gc_mark = 1; /* Mark all the sections in the group. */ group_sec = elf_section_data (sec)->next_in_group; if (group_sec && !group_sec->gc_mark) if (!elf_gc_mark (info, group_sec, gc_mark_hook)) return FALSE; /* Look through the section relocs. */ ret = TRUE; if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0) { Elf_Internal_Rela *relstart, *rel, *relend; Elf_Internal_Shdr *symtab_hdr; struct elf_link_hash_entry **sym_hashes; size_t nlocsyms; size_t extsymoff; bfd *input_bfd = sec->owner; struct elf_backend_data *bed = get_elf_backend_data (input_bfd); Elf_Internal_Sym *isym = NULL; symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; sym_hashes = elf_sym_hashes (input_bfd); /* Read the local symbols. */ if (elf_bad_symtab (input_bfd)) { nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym); extsymoff = 0; } else extsymoff = nlocsyms = symtab_hdr->sh_info; isym = (Elf_Internal_Sym *) symtab_hdr->contents; if (isym == NULL && nlocsyms != 0) { isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0, NULL, NULL, NULL); if (isym == NULL) return FALSE; } /* Read the relocations. */ relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, (Elf_Internal_Rela *) NULL, info->keep_memory); if (relstart == NULL) { ret = FALSE; goto out1; } relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel; for (rel = relstart; rel < relend; rel++) { unsigned long r_symndx; asection *rsec; struct elf_link_hash_entry *h; r_symndx = ELF_R_SYM (rel->r_info); if (r_symndx == 0) continue; if (r_symndx >= nlocsyms || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL) { h = sym_hashes[r_symndx - extsymoff]; rsec = (*gc_mark_hook) (sec, info, rel, h, NULL); } else { rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]); } if (rsec && !rsec->gc_mark) { if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour) rsec->gc_mark = 1; else if (!elf_gc_mark (info, rsec, gc_mark_hook)) { ret = FALSE; goto out2; } } } out2: if (elf_section_data (sec)->relocs != relstart) free (relstart); out1: if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym) { if (! info->keep_memory) free (isym); else symtab_hdr->contents = (unsigned char *) isym; } } return ret; } /* The sweep phase of garbage collection. Remove all garbage sections. */ typedef bfd_boolean (*gc_sweep_hook_fn) PARAMS ((bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *)); static bfd_boolean elf_gc_sweep (info, gc_sweep_hook) struct bfd_link_info *info; gc_sweep_hook_fn gc_sweep_hook; { bfd *sub; for (sub = info->input_bfds; sub != NULL; sub = sub->link_next) { asection *o; if (bfd_get_flavour (sub) != bfd_target_elf_flavour) continue; for (o = sub->sections; o != NULL; o = o->next) { /* Keep special sections. Keep .debug sections. */ if ((o->flags & SEC_LINKER_CREATED) || (o->flags & SEC_DEBUGGING)) o->gc_mark = 1; if (o->gc_mark) continue; /* Skip sweeping sections already excluded. */ if (o->flags & SEC_EXCLUDE) continue; /* Since this is early in the link process, it is simple to remove a section from the output. */ o->flags |= SEC_EXCLUDE; /* But we also have to update some of the relocation info we collected before. */ if (gc_sweep_hook && (o->flags & SEC_RELOC) && o->reloc_count > 0) { Elf_Internal_Rela *internal_relocs; bfd_boolean r; internal_relocs = _bfd_elf_link_read_relocs (o->owner, o, NULL, (Elf_Internal_Rela *) NULL, info->keep_memory); if (internal_relocs == NULL) return FALSE; r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs); if (elf_section_data (o)->relocs != internal_relocs) free (internal_relocs); if (!r) return FALSE; } } } /* Remove the symbols that were in the swept sections from the dynamic symbol table. GCFIXME: Anyone know how to get them out of the static symbol table as well? */ { int i = 0; elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol, (PTR) &i); elf_hash_table (info)->dynsymcount = i; } return TRUE; } /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */ static bfd_boolean elf_gc_sweep_symbol (h, idxptr) struct elf_link_hash_entry *h; PTR idxptr; { int *idx = (int *) idxptr; if (h->root.type == bfd_link_hash_warning) h = (struct elf_link_hash_entry *) h->root.u.i.link; if (h->dynindx != -1 && ((h->root.type != bfd_link_hash_defined && h->root.type != bfd_link_hash_defweak) || h->root.u.def.section->gc_mark)) h->dynindx = (*idx)++; return TRUE; } /* Propogate collected vtable information. This is called through elf_link_hash_traverse. */ static bfd_boolean elf_gc_propagate_vtable_entries_used (h, okp) struct elf_link_hash_entry *h; PTR okp; { if (h->root.type == bfd_link_hash_warning) h = (struct elf_link_hash_entry *) h->root.u.i.link; /* Those that are not vtables. */ if (h->vtable_parent == NULL) return TRUE; /* Those vtables that do not have parents, we cannot merge. */ if (h->vtable_parent == (struct elf_link_hash_entry *) -1) return TRUE; /* If we've already been done, exit. */ if (h->vtable_entries_used && h->vtable_entries_used[-1]) return TRUE; /* Make sure the parent's table is up to date. */ elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp); if (h->vtable_entries_used == NULL) { /* None of this table's entries were referenced. Re-use the parent's table. */ h->vtable_entries_used = h->vtable_parent->vtable_entries_used; h->vtable_entries_size = h->vtable_parent->vtable_entries_size; } else { size_t n; bfd_boolean *cu, *pu; /* Or the parent's entries into ours. */ cu = h->vtable_entries_used; cu[-1] = TRUE; pu = h->vtable_parent->vtable_entries_used; if (pu != NULL) { asection *sec = h->root.u.def.section; struct elf_backend_data *bed = get_elf_backend_data (sec->owner); unsigned int log_file_align = bed->s->log_file_align; n = h->vtable_parent->vtable_entries_size >> log_file_align; while (n--) { if (*pu) *cu = TRUE; pu++; cu++; } } } return TRUE; } static bfd_boolean elf_gc_smash_unused_vtentry_relocs (h, okp) struct elf_link_hash_entry *h; PTR okp; { asection *sec; bfd_vma hstart, hend; Elf_Internal_Rela *relstart, *relend, *rel; struct elf_backend_data *bed; unsigned int log_file_align; if (h->root.type == bfd_link_hash_warning) h = (struct elf_link_hash_entry *) h->root.u.i.link; /* Take care of both those symbols that do not describe vtables as well as those that are not loaded. */ if (h->vtable_parent == NULL) return TRUE; BFD_ASSERT (h->root.type == bfd_link_hash_defined || h->root.type == bfd_link_hash_defweak); sec = h->root.u.def.section; hstart = h->root.u.def.value; hend = hstart + h->size; relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, TRUE); if (!relstart) return *(bfd_boolean *) okp = FALSE; bed = get_elf_backend_data (sec->owner); log_file_align = bed->s->log_file_align; relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel; for (rel = relstart; rel < relend; ++rel) if (rel->r_offset >= hstart && rel->r_offset < hend) { /* If the entry is in use, do nothing. */ if (h->vtable_entries_used && (rel->r_offset - hstart) < h->vtable_entries_size) { bfd_vma entry = (rel->r_offset - hstart) >> log_file_align; if (h->vtable_entries_used[entry]) continue; } /* Otherwise, kill it. */ rel->r_offset = rel->r_info = rel->r_addend = 0; } return TRUE; } /* Do mark and sweep of unused sections. */ bfd_boolean elf_gc_sections (abfd, info) bfd *abfd; struct bfd_link_info *info; { bfd_boolean ok = TRUE; bfd *sub; asection * (*gc_mark_hook) PARAMS ((asection *, struct bfd_link_info *, Elf_Internal_Rela *, struct elf_link_hash_entry *h, Elf_Internal_Sym *)); if (!get_elf_backend_data (abfd)->can_gc_sections || info->relocateable || info->emitrelocations || elf_hash_table (info)->dynamic_sections_created) return TRUE; /* Apply transitive closure to the vtable entry usage info. */ elf_link_hash_traverse (elf_hash_table (info), elf_gc_propagate_vtable_entries_used, (PTR) &ok); if (!ok) return FALSE; /* Kill the vtable relocations that were not used. */ elf_link_hash_traverse (elf_hash_table (info), elf_gc_smash_unused_vtentry_relocs, (PTR) &ok); if (!ok) return FALSE; /* Grovel through relocs to find out who stays ... */ gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook; for (sub = info->input_bfds; sub != NULL; sub = sub->link_next) { asection *o; if (bfd_get_flavour (sub) != bfd_target_elf_flavour) continue; for (o = sub->sections; o != NULL; o = o->next) { if (o->flags & SEC_KEEP) if (!elf_gc_mark (info, o, gc_mark_hook)) return FALSE; } } /* ... and mark SEC_EXCLUDE for those that go. */ if (!elf_gc_sweep (info, get_elf_backend_data (abfd)->gc_sweep_hook)) return FALSE; return TRUE; } /* Called from check_relocs to record the existance of a VTINHERIT reloc. */ bfd_boolean elf_gc_record_vtinherit (abfd, sec, h, offset) bfd *abfd; asection *sec; struct elf_link_hash_entry *h; bfd_vma offset; { struct elf_link_hash_entry **sym_hashes, **sym_hashes_end; struct elf_link_hash_entry **search, *child; bfd_size_type extsymcount; /* The sh_info field of the symtab header tells us where the external symbols start. We don't care about the local symbols at this point. */ extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym); if (!elf_bad_symtab (abfd)) extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info; sym_hashes = elf_sym_hashes (abfd); sym_hashes_end = sym_hashes + extsymcount; /* Hunt down the child symbol, which is in this section at the same offset as the relocation. */ for (search = sym_hashes; search != sym_hashes_end; ++search) { if ((child = *search) != NULL && (child->root.type == bfd_link_hash_defined || child->root.type == bfd_link_hash_defweak) && child->root.u.def.section == sec && child->root.u.def.value == offset) goto win; } (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT", bfd_archive_filename (abfd), sec->name, (unsigned long) offset); bfd_set_error (bfd_error_invalid_operation); return FALSE; win: if (!h) { /* This *should* only be the absolute section. It could potentially be that someone has defined a non-global vtable though, which would be bad. It isn't worth paging in the local symbols to be sure though; that case should simply be handled by the assembler. */ child->vtable_parent = (struct elf_link_hash_entry *) -1; } else child->vtable_parent = h; return TRUE; } /* Called from check_relocs to record the existance of a VTENTRY reloc. */ bfd_boolean elf_gc_record_vtentry (abfd, sec, h, addend) bfd *abfd ATTRIBUTE_UNUSED; asection *sec ATTRIBUTE_UNUSED; struct elf_link_hash_entry *h; bfd_vma addend; { struct elf_backend_data *bed = get_elf_backend_data (abfd); unsigned int log_file_align = bed->s->log_file_align; if (addend >= h->vtable_entries_size) { size_t size, bytes; bfd_boolean *ptr = h->vtable_entries_used; /* While the symbol is undefined, we have to be prepared to handle a zero size. */ if (h->root.type == bfd_link_hash_undefined) size = addend; else { size = h->size; if (size < addend) { /* Oops! We've got a reference past the defined end of the table. This is probably a bug -- shall we warn? */ size = addend; } } /* Allocate one extra entry for use as a "done" flag for the consolidation pass. */ bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean); if (ptr) { ptr = bfd_realloc (ptr - 1, (bfd_size_type) bytes); if (ptr != NULL) { size_t oldbytes; oldbytes = (((h->vtable_entries_size >> log_file_align) + 1) * sizeof (bfd_boolean)); memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes); } } else ptr = bfd_zmalloc ((bfd_size_type) bytes); if (ptr == NULL) return FALSE; /* And arrange for that done flag to be at index -1. */ h->vtable_entries_used = ptr + 1; h->vtable_entries_size = size; } h->vtable_entries_used[addend >> log_file_align] = TRUE; return TRUE; } /* And an accompanying bit to work out final got entry offsets once we're done. Should be called from final_link. */ bfd_boolean elf_gc_common_finalize_got_offsets (abfd, info) bfd *abfd; struct bfd_link_info *info; { bfd *i; struct elf_backend_data *bed = get_elf_backend_data (abfd); bfd_vma gotoff; /* The GOT offset is relative to the .got section, but the GOT header is put into the .got.plt section, if the backend uses it. */ if (bed->want_got_plt) gotoff = 0; else gotoff = bed->got_header_size; /* Do the local .got entries first. */ for (i = info->input_bfds; i; i = i->link_next) { bfd_signed_vma *local_got; bfd_size_type j, locsymcount; Elf_Internal_Shdr *symtab_hdr; if (bfd_get_flavour (i) != bfd_target_elf_flavour) continue; local_got = elf_local_got_refcounts (i); if (!local_got) continue; symtab_hdr = &elf_tdata (i)->symtab_hdr; if (elf_bad_symtab (i)) locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym); else locsymcount = symtab_hdr->sh_info; for (j = 0; j < locsymcount; ++j) { if (local_got[j] > 0) { local_got[j] = gotoff; gotoff += ARCH_SIZE / 8; } else local_got[j] = (bfd_vma) -1; } } /* Then the global .got entries. .plt refcounts are handled by adjust_dynamic_symbol */ elf_link_hash_traverse (elf_hash_table (info), elf_gc_allocate_got_offsets, (PTR) &gotoff); return TRUE; } /* We need a special top-level link routine to convert got reference counts to real got offsets. */ static bfd_boolean elf_gc_allocate_got_offsets (h, offarg) struct elf_link_hash_entry *h; PTR offarg; { bfd_vma *off = (bfd_vma *) offarg; if (h->root.type == bfd_link_hash_warning) h = (struct elf_link_hash_entry *) h->root.u.i.link; if (h->got.refcount > 0) { h->got.offset = off[0]; off[0] += ARCH_SIZE / 8; } else h->got.offset = (bfd_vma) -1; return TRUE; } /* Many folk need no more in the way of final link than this, once got entry reference counting is enabled. */ bfd_boolean elf_gc_common_final_link (abfd, info) bfd *abfd; struct bfd_link_info *info; { if (!elf_gc_common_finalize_got_offsets (abfd, info)) return FALSE; /* Invoke the regular ELF backend linker to do all the work. */ return elf_bfd_final_link (abfd, info); } /* This function will be called though elf_link_hash_traverse to store all hash value of the exported symbols in an array. */ static bfd_boolean elf_collect_hash_codes (h, data) struct elf_link_hash_entry *h; PTR data; { unsigned long **valuep = (unsigned long **) data; const char *name; char *p; unsigned long ha; char *alc = NULL; if (h->root.type == bfd_link_hash_warning) h = (struct elf_link_hash_entry *) h->root.u.i.link; /* Ignore indirect symbols. These are added by the versioning code. */ if (h->dynindx == -1) return TRUE; name = h->root.root.string; p = strchr (name, ELF_VER_CHR); if (p != NULL) { alc = bfd_malloc ((bfd_size_type) (p - name + 1)); memcpy (alc, name, (size_t) (p - name)); alc[p - name] = '\0'; name = alc; } /* Compute the hash value. */ ha = bfd_elf_hash (name); /* Store the found hash value in the array given as the argument. */ *(*valuep)++ = ha; /* And store it in the struct so that we can put it in the hash table later. */ h->elf_hash_value = ha; if (alc != NULL) free (alc); return TRUE; } bfd_boolean elf_reloc_symbol_deleted_p (offset, cookie) bfd_vma offset; PTR cookie; { struct elf_reloc_cookie *rcookie = (struct elf_reloc_cookie *) cookie; if (rcookie->bad_symtab) rcookie->rel = rcookie->rels; for (; rcookie->rel < rcookie->relend; rcookie->rel++) { unsigned long r_symndx; if (! rcookie->bad_symtab) if (rcookie->rel->r_offset > offset) return FALSE; if (rcookie->rel->r_offset != offset) continue; r_symndx = ELF_R_SYM (rcookie->rel->r_info); if (r_symndx == SHN_UNDEF) return TRUE; if (r_symndx >= rcookie->locsymcount || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL) { struct elf_link_hash_entry *h; h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff]; 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; if ((h->root.type == bfd_link_hash_defined || h->root.type == bfd_link_hash_defweak) && elf_discarded_section (h->root.u.def.section)) return TRUE; else return FALSE; } else { /* It's not a relocation against a global symbol, but it could be a relocation against a local symbol for a discarded section. */ asection *isec; Elf_Internal_Sym *isym; /* Need to: get the symbol; get the section. */ isym = &rcookie->locsyms[r_symndx]; if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE) { isec = section_from_elf_index (rcookie->abfd, isym->st_shndx); if (isec != NULL && elf_discarded_section (isec)) return TRUE; } } return FALSE; } return FALSE; } /* Discard unneeded references to discarded sections. Returns TRUE if any section's size was changed. */ /* This function assumes that the relocations are in sorted order, which is true for all known assemblers. */ bfd_boolean elf_bfd_discard_info (output_bfd, info) bfd *output_bfd; struct bfd_link_info *info; { struct elf_reloc_cookie cookie; asection *stab, *eh; Elf_Internal_Shdr *symtab_hdr; struct elf_backend_data *bed; bfd *abfd; unsigned int count; bfd_boolean ret = FALSE; if (info->traditional_format || info->hash->creator->flavour != bfd_target_elf_flavour || ! is_elf_hash_table (info)) return FALSE; for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next) { if (bfd_get_flavour (abfd) != bfd_target_elf_flavour) continue; bed = get_elf_backend_data (abfd); if ((abfd->flags & DYNAMIC) != 0) continue; eh = bfd_get_section_by_name (abfd, ".eh_frame"); if (info->relocateable || (eh != NULL && (eh->_raw_size == 0 || bfd_is_abs_section (eh->output_section)))) eh = NULL; stab = bfd_get_section_by_name (abfd, ".stab"); if (stab != NULL && (stab->_raw_size == 0 || bfd_is_abs_section (stab->output_section) || stab->sec_info_type != ELF_INFO_TYPE_STABS)) stab = NULL; if (stab == NULL && eh == NULL && bed->elf_backend_discard_info == NULL) continue; symtab_hdr = &elf_tdata (abfd)->symtab_hdr; cookie.abfd = abfd; cookie.sym_hashes = elf_sym_hashes (abfd); cookie.bad_symtab = elf_bad_symtab (abfd); if (cookie.bad_symtab) { cookie.locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym); cookie.extsymoff = 0; } else { cookie.locsymcount = symtab_hdr->sh_info; cookie.extsymoff = symtab_hdr->sh_info; } cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents; if (cookie.locsyms == NULL && cookie.locsymcount != 0) { cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr, cookie.locsymcount, 0, NULL, NULL, NULL); if (cookie.locsyms == NULL) return FALSE; } if (stab != NULL) { cookie.rels = NULL; count = stab->reloc_count; if (count != 0) cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, (PTR) NULL, (Elf_Internal_Rela *) NULL, info->keep_memory); if (cookie.rels != NULL) { cookie.rel = cookie.rels; cookie.relend = cookie.rels; cookie.relend += count * bed->s->int_rels_per_ext_rel; if (_bfd_discard_section_stabs (abfd, stab, elf_section_data (stab)->sec_info, elf_reloc_symbol_deleted_p, &cookie)) ret = TRUE; if (elf_section_data (stab)->relocs != cookie.rels) free (cookie.rels); } } if (eh != NULL) { cookie.rels = NULL; count = eh->reloc_count; if (count != 0) cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, (PTR) NULL, (Elf_Internal_Rela *) NULL, info->keep_memory); cookie.rel = cookie.rels; cookie.relend = cookie.rels; if (cookie.rels != NULL) cookie.relend += count * bed->s->int_rels_per_ext_rel; if (_bfd_elf_discard_section_eh_frame (abfd, info, eh, elf_reloc_symbol_deleted_p, &cookie)) ret = TRUE; if (cookie.rels != NULL && elf_section_data (eh)->relocs != cookie.rels) free (cookie.rels); } if (bed->elf_backend_discard_info != NULL && (*bed->elf_backend_discard_info) (abfd, &cookie, info)) ret = TRUE; if (cookie.locsyms != NULL && symtab_hdr->contents != (unsigned char *) cookie.locsyms) { if (! info->keep_memory) free (cookie.locsyms); else symtab_hdr->contents = (unsigned char *) cookie.locsyms; } } if (info->eh_frame_hdr && !info->relocateable && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info)) ret = TRUE; return ret; } static bfd_boolean elf_section_ignore_discarded_relocs (sec) asection *sec; { struct elf_backend_data *bed; switch (sec->sec_info_type) { case ELF_INFO_TYPE_STABS: case ELF_INFO_TYPE_EH_FRAME: return TRUE; default: break; } bed = get_elf_backend_data (sec->owner); if (bed->elf_backend_ignore_discarded_relocs != NULL && (*bed->elf_backend_ignore_discarded_relocs) (sec)) return TRUE; return FALSE; }