diff options
Diffstat (limited to 'bfd/elflink.c')
| -rw-r--r-- | bfd/elflink.c | 1347 |
1 files changed, 1334 insertions, 13 deletions
diff --git a/bfd/elflink.c b/bfd/elflink.c index fce550d..61495fc 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -24,6 +24,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "libbfd.h" #define ARCH_SIZE 0 #include "elf-bfd.h" +#include "safe-ctype.h" bfd_boolean _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info) @@ -2626,10 +2627,10 @@ _bfd_elf_add_dynamic_entry (struct bfd_link_info *info, otherwise just check whether one already exists. Returns -1 on error, 1 if a DT_NEEDED tag already exists, and 0 on success. */ -int -_bfd_elf_add_dt_needed_tag (struct bfd_link_info *info, - const char *soname, - bfd_boolean do_it) +static int +elf_add_dt_needed_tag (struct bfd_link_info *info, + const char *soname, + bfd_boolean do_it) { struct elf_link_hash_table *hash_table; bfd_size_type oldsize; @@ -2680,8 +2681,8 @@ _bfd_elf_add_dt_needed_tag (struct bfd_link_info *info, } /* Sort symbol by value and section. */ -int -_bfd_elf_sort_symbol (const void *arg1, const void *arg2) +static int +elf_sort_symbol (const void *arg1, const void *arg2) { const struct elf_link_hash_entry *h1; const struct elf_link_hash_entry *h2; @@ -2700,7 +2701,7 @@ _bfd_elf_sort_symbol (const void *arg1, const void *arg2) } return 0; } - + /* This function is used to adjust offsets into .dynstr for dynamic symbols. This is called via elf_link_hash_traverse. */ @@ -2720,8 +2721,8 @@ elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data) /* Assign string offsets in .dynstr, update all structures referencing them. */ -bfd_boolean -_bfd_elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info) +static bfd_boolean +elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info) { struct elf_link_hash_table *hash_table = elf_hash_table (info); struct elf_link_local_dynamic_entry *entry; @@ -2841,6 +2842,1309 @@ _bfd_elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info) return TRUE; } +/* Add symbols from an ELF object file to the linker hash table. */ + +static bfd_boolean +elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info) +{ + bfd_boolean (*add_symbol_hook) + (bfd *, struct bfd_link_info *, const Elf_Internal_Sym *, + const char **, flagword *, asection **, bfd_vma *); + bfd_boolean (*check_relocs) + (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; + const struct elf_backend_data *bed; + bfd_boolean add_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->relocatable + || !is_elf_hash_table (hash_table) + || hash_table->root.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; + bfd_size_type prefix_len; + const char * gnu_warning_prefix = _("warning: "); + + 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) + { + 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); + prefix_len = strlen (gnu_warning_prefix); + msg = bfd_alloc (abfd, prefix_len + sz + 1); + if (msg == NULL) + goto error_return; + + strcpy (msg, gnu_warning_prefix); + if (! bfd_get_section_contents (abfd, s, msg + prefix_len, 0, sz)) + goto error_return; + + msg[prefix_len + sz] = '\0'; + + if (! (_bfd_generic_link_add_one_symbol + (info, abfd, name, BSF_WARNING, s, 0, msg, + FALSE, collect, NULL))) + goto error_return; + + if (! info->relocatable) + { + /* Clobber the section size so that the warning does + not get copied into the output file. */ + s->_raw_size = 0; + } + } + } + } + + add_needed = TRUE; + 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 (hash_table) + && hash_table->root.creator == abfd->xvec + && ! hash_table->dynamic_sections_created) + { + if (! _bfd_elf_link_create_dynamic_sections (abfd, info)) + goto error_return; + } + } + else if (!is_elf_hash_table (hash_table)) + goto error_return; + else + { + asection *s; + const char *soname = NULL; + struct bfd_link_needed_list *rpath = NULL, *runpath = NULL; + int ret; + + /* 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; + + /* If this dynamic lib was specified on the command line with + --as-needed in effect, then we don't want to add a DT_NEEDED + tag unless the lib is actually used. Similary for libs brought + in by another lib's DT_NEEDED. */ + add_needed = elf_dyn_lib_class (abfd) == DYN_NORMAL; + + s = bfd_get_section_by_name (abfd, ".dynamic"); + if (s != NULL) + { + bfd_byte *dynbuf; + bfd_byte *extdyn; + int elfsec; + unsigned long shlink; + + dynbuf = bfd_malloc (s->_raw_size); + if (dynbuf == NULL) + goto error_return; + + if (! bfd_get_section_contents (abfd, s, dynbuf, 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; + + for (extdyn = dynbuf; + extdyn < dynbuf + s->_raw_size; + extdyn += bed->s->sizeof_dyn) + { + Elf_Internal_Dyn dyn; + + bed->s->swap_dyn_in (abfd, extdyn, &dyn); + if (dyn.d_tag == DT_SONAME) + { + unsigned int tagv = dyn.d_un.d_val; + soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv); + if (soname == 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 = 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, 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 = 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, 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 = 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, 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 (! _bfd_elf_link_create_dynamic_sections (abfd, info)) + 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 (soname == NULL || *soname == '\0') + { + soname = elf_dt_name (abfd); + if (soname == NULL || *soname == '\0') + soname = bfd_get_filename (abfd); + } + + /* Save the SONAME because sometimes the linker emulation code + will need to know it. */ + elf_dt_name (abfd) = soname; + + ret = elf_add_dt_needed_tag (info, soname, add_needed); + if (ret < 0) + goto error_return; + + /* 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. */ + if (ret > 0) + return TRUE; + } + + /* 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 / bed->s->sizeof_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 = 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 = 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 (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. Unfortunately, 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 = bfd_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 == 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 == NULL) + continue; + } + + /* Sanity check that all possibilities were handled. */ + if (sec == 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 (is_elf_hash_table (hash_table)) + { + 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 = bfd_alloc (abfd, 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)) + 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, 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 + && is_elf_hash_table (hash_table) + && 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 (is_elf_hash_table (hash_table)) + { + 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 overridden 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 != NULL + && (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 (bed->elf_backend_merge_symbol_attribute) + (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition, + dynamic); + + 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)) + 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); + dynsym = FALSE; + break; + } + + if (!add_needed + && definition + && dynsym + && (h->elf_link_hash_flags + & ELF_LINK_HASH_REF_REGULAR) != 0) + { + int ret; + const char *soname = elf_dt_name (abfd); + + /* A symbol from a library loaded via DT_NEEDED of some + other library is referenced by a regular object. + Add a DT_NEEDED entry for it. */ + add_needed = TRUE; + ret = elf_add_dt_needed_tag (info, soname, add_needed); + if (ret < 0) + goto error_free_vers; + + BFD_ASSERT (ret == 0); + } + } + } + + /* 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 (&hash_table->root, 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. */ + if (weaks != NULL) + { + struct elf_link_hash_entry **hpp; + struct elf_link_hash_entry **hppend; + struct elf_link_hash_entry **sorted_sym_hash; + struct elf_link_hash_entry *h; + size_t sym_count; + + /* Since we have to search the whole symbol list for each weak + defined symbol, search time for N weak defined symbols will be + O(N^2). Binary search will cut it down to O(NlogN). */ + amt = extsymcount * sizeof (struct elf_link_hash_entry *); + sorted_sym_hash = bfd_malloc (amt); + if (sorted_sym_hash == NULL) + goto error_return; + sym_hash = sorted_sym_hash; + hpp = elf_sym_hashes (abfd); + hppend = hpp + extsymcount; + sym_count = 0; + for (; hpp < hppend; hpp++) + { + h = *hpp; + if (h != NULL + && h->root.type == bfd_link_hash_defined + && h->type != STT_FUNC) + { + *sym_hash = h; + sym_hash++; + sym_count++; + } + } + + qsort (sorted_sym_hash, sym_count, + sizeof (struct elf_link_hash_entry *), + elf_sort_symbol); + + while (weaks != NULL) + { + struct elf_link_hash_entry *hlook; + asection *slook; + bfd_vma vlook; + long ilook; + size_t i, j, idx; + + 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; + + ilook = -1; + i = 0; + j = sym_count; + while (i < j) + { + bfd_signed_vma vdiff; + idx = (i + j) / 2; + h = sorted_sym_hash [idx]; + vdiff = vlook - h->root.u.def.value; + if (vdiff < 0) + j = idx; + else if (vdiff > 0) + i = idx + 1; + else + { + long sdiff = slook - h->root.u.def.section; + if (sdiff < 0) + j = idx; + else if (sdiff > 0) + i = idx + 1; + else + { + ilook = idx; + break; + } + } + } + + /* We didn't find a value/section match. */ + if (ilook == -1) + continue; + + for (i = ilook; i < sym_count; i++) + { + h = sorted_sym_hash [i]; + + /* Stop if value or section doesn't match. */ + if (h->root.u.def.value != vlook + || h->root.u.def.section != slook) + break; + else if (h != hlook) + { + 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; + } + } + } + + free (sorted_sym_hash); + } + + /* 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 + && is_elf_hash_table (hash_table) + && hash_table->root.creator == abfd->xvec + && 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, NULL, 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 + && is_elf_hash_table (hash_table) + && (info->strip != strip_all && info->strip != strip_debugger)) + { + asection *stabstr; + + stabstr = bfd_get_section_by_name (abfd, ".stabstr"); + if (stabstr != NULL) + { + bfd_size_type string_offset = 0; + asection *stab; + + for (stab = abfd->sections; stab; stab = stab->next) + if (strncmp (".stab", stab->name, 5) == 0 + && (!stab->name[5] || + (stab->name[5] == '.' && ISDIGIT (stab->name[6]))) + && (stab->flags & SEC_MERGE) == 0 + && !bfd_is_abs_section (stab->output_section)) + { + 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, + &string_offset)) + goto error_return; + if (secdata->sec_info) + stab->sec_info_type = ELF_INFO_TYPE_STABS; + } + } + } + + if (! info->relocatable + && ! dynamic + && is_elf_hash_table (hash_table)) + { + 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 (hash_table)) + { + /* Add this bfd to the loaded list. */ + struct elf_link_loaded_list *n; + + n = 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 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 @@ -2866,9 +4170,8 @@ _bfd_elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info) Unfortunately, we do have to make multiple passes over the symbol table until nothing further is resolved. */ -bfd_boolean -_bfd_elf_link_add_archive_symbols (bfd *abfd, - struct bfd_link_info *info) +static bfd_boolean +elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info) { symindex c; bfd_boolean *defined = NULL; @@ -3065,6 +4368,24 @@ _bfd_elf_link_add_archive_symbols (bfd *abfd, free (included); return FALSE; } + +/* Given an ELF BFD, add symbols to the global hash table as + appropriate. */ + +bfd_boolean +bfd_elf_link_add_symbols (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; + } +} /* This function will be called though elf_link_hash_traverse to store all hash value of the exported symbols in an array. */ @@ -4026,7 +5347,7 @@ bfd_elf_size_dynamic_sections (bfd *output_bfd, s = bfd_get_section_by_name (dynobj, ".dynstr"); BFD_ASSERT (s != NULL); - _bfd_elf_finalize_dynstr (output_bfd, info); + elf_finalize_dynstr (output_bfd, info); s->_raw_size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr); |