X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=ld%2Femultempl%2Felf32.em;h=71e34b5abc0039ccbcb17c49f8fe6ffa81c98f67;hb=6cc7365e2b682389efdaf16431189f7762805bc3;hp=1ce59dd9fda108c0135a330fd4717a336186823f;hpb=2a9fa50cd8ae5dc1e99056c9683bece549e0b68f;p=deliverable%2Fbinutils-gdb.git diff --git a/ld/emultempl/elf32.em b/ld/emultempl/elf32.em index 1ce59dd9fd..71e34b5abc 100644 --- a/ld/emultempl/elf32.em +++ b/ld/emultempl/elf32.em @@ -4,7 +4,7 @@ cat >e${EMULATION_NAME}.c < ELF support by Ian Lance Taylor @@ -22,35 +22,511 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software -Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ +Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #define TARGET_IS_${EMULATION_NAME} #include "bfd.h" #include "sysdep.h" + +#include + #include "bfdlink.h" #include "ld.h" -#include "config.h" #include "ldmain.h" #include "ldemul.h" #include "ldfile.h" #include "ldmisc.h" #include "ldexp.h" #include "ldlang.h" +#include "ldgram.h" static void gld${EMULATION_NAME}_before_parse PARAMS ((void)); +static boolean gld${EMULATION_NAME}_open_dynamic_archive + PARAMS ((const char *, search_dirs_type *, lang_input_statement_type *)); +static void gld${EMULATION_NAME}_after_open PARAMS ((void)); +static void gld${EMULATION_NAME}_check_needed + PARAMS ((lang_input_statement_type *)); +static void gld${EMULATION_NAME}_stat_needed + PARAMS ((lang_input_statement_type *)); +static boolean gld${EMULATION_NAME}_search_needed + PARAMS ((const char *, const char *)); +static boolean gld${EMULATION_NAME}_try_needed PARAMS ((const char *)); static void gld${EMULATION_NAME}_before_allocation PARAMS ((void)); static void gld${EMULATION_NAME}_find_statement_assignment PARAMS ((lang_statement_union_type *)); static void gld${EMULATION_NAME}_find_exp_assignment PARAMS ((etree_type *)); +static boolean gld${EMULATION_NAME}_place_orphan + PARAMS ((lang_input_statement_type *, asection *)); +static void gld${EMULATION_NAME}_place_section + PARAMS ((lang_statement_union_type *)); static char *gld${EMULATION_NAME}_get_script PARAMS ((int *isfile)); static void gld${EMULATION_NAME}_before_parse() { - ldfile_output_architecture = bfd_arch_${ARCH}; - config.dynamic_link = true; + ldfile_output_architecture = bfd_arch_`echo ${ARCH} | sed -e 's/:.*//'`; + config.dynamic_link = ${DYNAMIC_LINK-true}; +} + +/* Try to open a dynamic archive. This is where we know that ELF + dynamic libraries have an extension of .so. */ + +static boolean +gld${EMULATION_NAME}_open_dynamic_archive (arch, search, entry) + const char *arch; + search_dirs_type *search; + lang_input_statement_type *entry; +{ + const char *filename; + char *string; + + if (! entry->is_archive) + return false; + + filename = entry->filename; + + string = (char *) xmalloc (strlen (search->name) + + strlen (filename) + + strlen (arch) + + sizeof "/lib.so"); + + sprintf (string, "%s/lib%s%s.so", search->name, filename, arch); + + if (! ldfile_try_open_bfd (string, entry)) + { + free (string); + return false; + } + + entry->filename = string; + + /* We have found a dynamic object to include in the link. The ELF + backend linker will create a DT_NEEDED entry in the .dynamic + section naming this file. If this file includes a DT_SONAME + entry, it will be used. Otherwise, the ELF linker will just use + the name of the file. For an archive found by searching, like + this one, the DT_NEEDED entry should consist of just the name of + the file, without the path information used to find it. Note + that we only need to do this if we have a dynamic object; an + archive will never be referenced by a DT_NEEDED entry. + + FIXME: This approach--using bfd_elf_set_dt_needed_name--is not + very pretty. I haven't been able to think of anything that is + pretty, though. */ + if (bfd_check_format (entry->the_bfd, bfd_object) + && (entry->the_bfd->flags & DYNAMIC) != 0) + { + char *needed_name; + + ASSERT (entry->is_archive && entry->search_dirs_flag); + needed_name = (char *) xmalloc (strlen (filename) + + strlen (arch) + + sizeof "lib.so"); + sprintf (needed_name, "lib%s%s.so", filename, arch); + bfd_elf_set_dt_needed_name (entry->the_bfd, needed_name); + } + + return true; +} + +EOF +if [ "x${host}" = "x${target}" ] ; then +cat >>e${EMULATION_NAME}.c <= alloc) + { + alloc *= 2; + b = (char *) xrealloc (b, alloc); + } + if (c != ':' + && c != ' ' + && c != '\t' + && c != '\n' + && c != ',') + { + b[len] = c; + ++len; + } + else + { + if (len > 0 && b[len - 1] != ':') + { + b[len] = ':'; + ++len; + } + } + } + + if (len > 0 && b[len - 1] == ':') + --len; + + if (len > 0) + b[len] = '\0'; + else + { + free (b); + b = NULL; + } + + fclose (f); + + ld_so_conf = b; + } + + initialized = true; + } + + if (ld_so_conf == NULL) + return false; + + return gld${EMULATION_NAME}_search_needed (ld_so_conf, name); +} + +EOF +fi +cat >>e${EMULATION_NAME}.c <next) + { + struct bfd_link_needed_list *ll; + const char *lib_path; + size_t len; + search_dirs_type *search; + + /* If we've already seen this file, skip it. */ + for (ll = needed; ll != l; ll = ll->next) + if (strcmp (ll->name, l->name) == 0) + break; + if (ll != l) + continue; + + /* See if this file was included in the link explicitly. */ + global_needed = l; + global_found = false; + lang_for_each_input_file (gld${EMULATION_NAME}_check_needed); + if (global_found) + continue; + + /* We need to find this file and include the symbol table. We + want to search for the file in the same way that the dynamic + linker will search. That means that we want to use + rpath_link, rpath, then the environment variable + LD_LIBRARY_PATH (native only), then the linker script + LIB_SEARCH_DIRS. We do not search using the -L arguments. */ + if (gld${EMULATION_NAME}_search_needed (command_line.rpath_link, + l->name)) + continue; + if (gld${EMULATION_NAME}_search_needed (command_line.rpath, l->name)) + continue; + if (command_line.rpath_link == NULL + && command_line.rpath == NULL) + { + lib_path = (const char *) getenv ("LD_RUN_PATH"); + if (gld${EMULATION_NAME}_search_needed (lib_path, l->name)) + continue; + } +EOF +if [ "x${host}" = "x${target}" ] ; then +cat >>e${EMULATION_NAME}.c <name)) + continue; +EOF +fi +cat >>e${EMULATION_NAME}.c <name); + for (search = search_head; search != NULL; search = search->next) + { + char *filename; + + if (search->cmdline) + continue; + filename = (char *) xmalloc (strlen (search->name) + len + 2); + sprintf (filename, "%s/%s", search->name, l->name); + if (gld${EMULATION_NAME}_try_needed (filename)) + break; + free (filename); + } + if (search != NULL) + continue; +EOF +if [ "x${host}" = "x${target}" ] ; then +cat >>e${EMULATION_NAME}.c <name)) + continue; +EOF +fi +cat >>e${EMULATION_NAME}.c <name, l->by); + } +} + +/* Search for a needed file in a path. */ + +static boolean +gld${EMULATION_NAME}_search_needed (path, name) + const char *path; + const char *name; +{ + const char *s; + size_t len; + + if (path == NULL || *path == '\0') + return false; + len = strlen (name); + while (1) + { + char *filename, *sset; + + s = strchr (path, ':'); + if (s == NULL) + s = path + strlen (path); + + filename = (char *) xmalloc (s - path + len + 2); + if (s == path) + sset = filename; + else + { + memcpy (filename, path, s - path); + filename[s - path] = '/'; + sset = filename + (s - path) + 1; + } + strcpy (sset, name); + + if (gld${EMULATION_NAME}_try_needed (filename)) + return true; + + free (filename); + + if (*s == '\0') + break; + path = s + 1; + } + + return false; +} + +/* This function is called for each possible name for a dynamic object + named by a DT_NEEDED entry. */ + +static boolean +gld${EMULATION_NAME}_try_needed (name) + const char *name; +{ + bfd *abfd; + + abfd = bfd_openr (name, bfd_get_target (output_bfd)); + if (abfd == NULL) + return false; + if (! bfd_check_format (abfd, bfd_object)) + { + (void) bfd_close (abfd); + return false; + } + if ((bfd_get_file_flags (abfd) & DYNAMIC) == 0) + { + (void) bfd_close (abfd); + return false; + } + + /* We've found a dynamic object matching the DT_NEEDED entry. */ + + /* We have already checked that there is no other input file of the + same name. We must now check again that we are not including the + same file twice. We need to do this because on many systems + libc.so is a symlink to, e.g., libc.so.1. The SONAME entry will + reference libc.so.1. If we have already included libc.so, we + don't want to include libc.so.1 if they are the same file, and we + can only check that using stat. */ + + if (bfd_stat (abfd, &global_stat) != 0) + einfo ("%F%P:%B: bfd_stat failed: %E\n", abfd); + global_found = false; + lang_for_each_input_file (gld${EMULATION_NAME}_stat_needed); + if (global_found) + { + /* Return true to indicate that we found the file, even though + we aren't going to do anything with it. */ + return true; + } + + /* Tell the ELF backend that don't want the output file to have a + DT_NEEDED entry for this file. */ + bfd_elf_set_dt_needed_name (abfd, ""); + + /* Add this file into the symbol table. */ + if (! bfd_link_add_symbols (abfd, &link_info)) + einfo ("%F%B: could not read symbols: %E\n", abfd); + + return true; +} + +/* See if an input file matches a DT_NEEDED entry by name. */ + +static void +gld${EMULATION_NAME}_check_needed (s) + lang_input_statement_type *s; +{ + if (global_found) + return; + + if (s->filename != NULL + && strcmp (s->filename, global_needed->name) == 0) + { + global_found = true; + return; + } + + if (s->the_bfd != NULL) + { + const char *soname; + + soname = bfd_elf_get_dt_soname (s->the_bfd); + if (soname != NULL + && strcmp (soname, global_needed->name) == 0) + { + global_found = true; + return; + } + } + + if (s->search_dirs_flag + && s->filename != NULL + && strchr (global_needed->name, '/') == NULL) + { + const char *f; + + f = strrchr (s->filename, '/'); + if (f != NULL + && strcmp (f + 1, global_needed->name) == 0) + { + global_found = true; + return; + } + } +} + +/* See if an input file matches a DT_NEEDED entry by running stat on + the file. */ + +static void +gld${EMULATION_NAME}_stat_needed (s) + lang_input_statement_type *s; +{ + struct stat st; + const char *suffix; + const char *soname; + const char *f; + + if (global_found) + return; + if (s->the_bfd == NULL) + return; + + if (bfd_stat (s->the_bfd, &st) != 0) + { + einfo ("%P:%B: bfd_stat failed: %E\n", s->the_bfd); + return; + } + + if (st.st_dev == global_stat.st_dev + && st.st_ino == global_stat.st_ino) + { + global_found = true; + return; + } + + /* We issue a warning if it looks like we are including two + different versions of the same shared library. For example, + there may be a problem if -lc picks up libc.so.6 but some other + shared library has a DT_NEEDED entry of libc.so.5. This is a + hueristic test, and it will only work if the name looks like + NAME.so.VERSION. FIXME: Depending on file names is error-prone. + If we really want to issue warnings about mixing version numbers + of shared libraries, we need to find a better way. */ + + if (strchr (global_needed->name, '/') != NULL) + return; + suffix = strstr (global_needed->name, ".so."); + if (suffix == NULL) + return; + suffix += sizeof ".so." - 1; + + soname = bfd_elf_get_dt_soname (s->the_bfd); + if (soname == NULL) + soname = s->filename; + + f = strrchr (soname, '/'); + if (f != NULL) + ++f; + else + f = soname; + + if (strncmp (f, global_needed->name, suffix - global_needed->name) == 0) + einfo ("%P: warning: %s, needed by %B, may conflict with %s\n", + global_needed->name, global_needed->by, f); } /* This is called after the sections have been attached to output @@ -59,6 +535,9 @@ gld${EMULATION_NAME}_before_parse() static void gld${EMULATION_NAME}_before_allocation () { + const char *rpath; + asection *sinterp; + /* If we are going to make any variable assignments, we need to let the ELF backend know about them in case the variables are referred to by dynamic objects. */ @@ -66,8 +545,94 @@ gld${EMULATION_NAME}_before_allocation () /* Let the ELF backend work out the sizes of any sections required by dynamic linking. */ - if (! bfd_elf32_size_dynamic_sections (output_bfd, &link_info)) + rpath = command_line.rpath; + if (rpath == NULL) + rpath = (const char *) getenv ("LD_RUN_PATH"); + if (! bfd_elf32_size_dynamic_sections (output_bfd, + command_line.soname, + rpath, + command_line.export_dynamic, + &link_info, + &sinterp)) einfo ("%P%F: failed to set dynamic section sizes: %E\n"); + + /* Let the user override the dynamic linker we are using. */ + if (command_line.interpreter != NULL + && sinterp != NULL) + { + sinterp->contents = (bfd_byte *) command_line.interpreter; + sinterp->_raw_size = strlen (command_line.interpreter) + 1; + } + + /* Look for any sections named .gnu.warning. As a GNU extensions, + we treat such sections as containing warning messages. We print + out the warning message, and then zero out the section size so + that it does not get copied into the output file. */ + + { + LANG_FOR_EACH_INPUT_STATEMENT (is) + { + asection *s; + bfd_size_type sz; + char *msg; + boolean ret; + + if (is->just_syms_flag) + continue; + + s = bfd_get_section_by_name (is->the_bfd, ".gnu.warning"); + if (s == NULL) + continue; + + sz = bfd_section_size (is->the_bfd, s); + msg = xmalloc ((size_t) sz + 1); + if (! bfd_get_section_contents (is->the_bfd, s, msg, (file_ptr) 0, sz)) + einfo ("%F%B: Can't read contents of section .gnu.warning: %E\n", + is->the_bfd); + msg[sz] = '\0'; + ret = link_info.callbacks->warning (&link_info, msg, + (const char *) NULL, + is->the_bfd, (asection *) NULL, + (bfd_vma) 0); + ASSERT (ret); + free (msg); + + /* Clobber the section size, so that we don't waste copying the + warning into the output file. */ + s->_raw_size = 0; + } + } + +#if defined (TARGET_IS_elf32bmip) || defined (TARGET_IS_elf32lmip) + /* For MIPS ELF the .reginfo section requires special handling. + Each input section is 24 bytes, and the final output section must + also be 24 bytes. We handle this by clobbering all but the first + input section size to 0. The .reginfo section is handled + specially by the backend code anyhow. */ + { + boolean found = false; + LANG_FOR_EACH_INPUT_STATEMENT (is) + { + asection *s; + + if (is->just_syms_flag) + continue; + + s = bfd_get_section_by_name (is->the_bfd, ".reginfo"); + if (s == NULL) + continue; + + if (! found) + { + found = true; + continue; + } + + s->_raw_size = 0; + s->_cooked_size = 0; + } + } +#endif } /* This is called by the before_allocation routine via @@ -89,13 +654,31 @@ static void gld${EMULATION_NAME}_find_exp_assignment (exp) etree_type *exp; { + struct bfd_link_hash_entry *h; + switch (exp->type.node_class) { + case etree_provide: + h = bfd_link_hash_lookup (link_info.hash, exp->assign.dst, + false, false, false); + if (h == NULL) + break; + + /* We call record_link_assignment even if the symbol is defined. + This is because if it is defined by a dynamic object, we + actually want to use the value defined by the linker script, + not the value from the dynamic object (because we are setting + symbols like etext). If the symbol is defined by a regular + object, then, as it happens, calling record_link_assignment + will do no harm. */ + + /* Fall through. */ case etree_assign: if (strcmp (exp->assign.dst, ".") != 0) { - if (! bfd_elf32_record_link_assignment (output_bfd, &link_info, - exp->assign.dst)) + if (! (bfd_elf32_record_link_assignment + (output_bfd, &link_info, exp->assign.dst, + exp->type.node_class == etree_provide ? true : false))) einfo ("%P%F: failed to record assignment to %s: %E\n", exp->assign.dst); } @@ -108,7 +691,7 @@ gld${EMULATION_NAME}_find_exp_assignment (exp) break; case etree_trinary: - gld${EMULATION_NAME}_find_exp_assignment (exp->trinary.lhs); + gld${EMULATION_NAME}_find_exp_assignment (exp->trinary.cond); gld${EMULATION_NAME}_find_exp_assignment (exp->trinary.lhs); gld${EMULATION_NAME}_find_exp_assignment (exp->trinary.rhs); break; @@ -122,6 +705,172 @@ gld${EMULATION_NAME}_find_exp_assignment (exp) } } +/* Place an orphan section. We use this to put random SHF_ALLOC + sections in the right segment. */ + +static asection *hold_section; +static lang_output_section_statement_type *hold_use; +static lang_output_section_statement_type *hold_text; +static lang_output_section_statement_type *hold_data; +static lang_output_section_statement_type *hold_bss; +static lang_output_section_statement_type *hold_rel; + +/*ARGSUSED*/ +static boolean +gld${EMULATION_NAME}_place_orphan (file, s) + lang_input_statement_type *file; + asection *s; +{ + lang_output_section_statement_type *place; + asection *snew, **pps; + lang_statement_list_type *old; + lang_statement_list_type add; + etree_type *address; + const char *secname, *ps; + lang_output_section_statement_type *os; + + if ((s->flags & SEC_ALLOC) == 0) + return false; + + /* Look through the script to see where to place this section. */ + hold_section = s; + hold_use = NULL; + lang_for_each_statement (gld${EMULATION_NAME}_place_section); + + if (hold_use != NULL) + { + /* We have already placed a section with this name. */ + wild_doit (&hold_use->children, s, hold_use, file); + return true; + } + + secname = bfd_get_section_name (s->owner, s); + + /* If this is a final link, then always put .gnu.warning.SYMBOL + sections into the .text section to get them out of the way. */ + if (! link_info.shared + && ! link_info.relocateable + && strncmp (secname, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0 + && hold_text != NULL) + { + wild_doit (&hold_text->children, s, hold_text, file); + return true; + } + + /* Decide which segment the section should go in based on the + section name and section flags. */ + place = NULL; + if ((s->flags & SEC_HAS_CONTENTS) == 0 + && hold_bss != NULL) + place = hold_bss; + else if ((s->flags & SEC_READONLY) == 0 + && hold_data != NULL) + place = hold_data; + else if (strncmp (secname, ".rel", 4) == 0 + && hold_rel != NULL) + place = hold_rel; + else if ((s->flags & SEC_READONLY) != 0 + && hold_text != NULL) + place = hold_text; + if (place == NULL) + return false; + + /* Create the section in the output file, and put it in the right + place. This shuffling is to make the output file look neater. */ + snew = bfd_make_section (output_bfd, secname); + if (snew == NULL) + einfo ("%P%F: output format %s cannot represent section called %s\n", + output_bfd->xvec->name, secname); + if (place->bfd_section != NULL) + { + for (pps = &output_bfd->sections; *pps != snew; pps = &(*pps)->next) + ; + *pps = snew->next; + snew->next = place->bfd_section->next; + place->bfd_section->next = snew; + } + + /* Start building a list of statements for this section. */ + old = stat_ptr; + stat_ptr = &add; + lang_list_init (stat_ptr); + + /* If the name of the section is representable in C, then create + symbols to mark the start and the end of the section. */ + for (ps = secname; *ps != '\0'; ps++) + if (! isalnum (*ps) && *ps != '_') + break; + if (*ps == '\0' && config.build_constructors) + { + char *symname; + + symname = (char *) xmalloc (ps - secname + sizeof "__start_"); + sprintf (symname, "__start_%s", secname); + lang_add_assignment (exp_assop ('=', symname, + exp_nameop (NAME, "."))); + } + + if (! link_info.relocateable) + address = NULL; + else + address = exp_intop ((bfd_vma) 0); + + lang_enter_output_section_statement (secname, address, 0, + (bfd_vma) 0, + (etree_type *) NULL, + (etree_type *) NULL, + (etree_type *) NULL); + + os = lang_output_section_statement_lookup (secname); + wild_doit (&os->children, s, os, file); + + lang_leave_output_section_statement ((bfd_vma) 0, "*default*"); + stat_ptr = &add; + + if (*ps == '\0' && config.build_constructors) + { + char *symname; + + symname = (char *) xmalloc (ps - secname + sizeof "__stop_"); + sprintf (symname, "__stop_%s", secname); + lang_add_assignment (exp_assop ('=', symname, + exp_nameop (NAME, "."))); + } + + /* Now stick the new statement list right after PLACE. */ + *add.tail = place->header.next; + place->header.next = add.head; + + stat_ptr = old; + + return true; +} + +static void +gld${EMULATION_NAME}_place_section (s) + lang_statement_union_type *s; +{ + lang_output_section_statement_type *os; + + if (s->header.type != lang_output_section_statement_enum) + return; + + os = &s->output_section_statement; + + if (strcmp (os->name, hold_section->name) == 0) + hold_use = os; + + if (strcmp (os->name, ".text") == 0) + hold_text = os; + else if (strcmp (os->name, ".data") == 0) + hold_data = os; + else if (strcmp (os->name, ".bss") == 0) + hold_bss = os; + else if (hold_rel == NULL + && strncmp (os->name, ".rel", 4) == 0) + hold_rel = os; +} + static char * gld${EMULATION_NAME}_get_script(isfile) int *isfile; @@ -150,6 +899,8 @@ cat >>e${EMULATION_NAME}.c <>e${EMULATION_NAME}.c <