# This shell script emits a C file. -*- C -*- # It does some substitutions. # This file is now misnamed, because it supports both 32 bit and 64 bit # ELF emulations. test -z "${ELFSIZE}" && ELFSIZE=32 if [ -z "$MACHINE" ]; then OUTPUT_ARCH=${ARCH} else OUTPUT_ARCH=${ARCH}:${MACHINE} fi fragment < ELF support by Ian Lance Taylor This file is part of the GNU Binutils. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ #define TARGET_IS_${EMULATION_NAME} #include "sysdep.h" #include "bfd.h" #include "libiberty.h" #include "safe-ctype.h" #include "getopt.h" #include "md5.h" #include "sha1.h" #include #include "bfdlink.h" #include "ld.h" #include "ldmain.h" #include "ldmisc.h" #include "ldexp.h" #include "ldlang.h" #include "ldfile.h" #include "ldemul.h" #include #include "elf/common.h" #include "elf-bfd.h" /* Declare functions used by various EXTRA_EM_FILEs. */ static void gld${EMULATION_NAME}_before_parse (void); static void gld${EMULATION_NAME}_after_open (void); static void gld${EMULATION_NAME}_before_allocation (void); static void gld${EMULATION_NAME}_after_allocation (void); static lang_output_section_statement_type *gld${EMULATION_NAME}_place_orphan (asection *, const char *, int); EOF if [ "x${USE_LIBPATH}" = xyes ] ; then case ${target} in *-*-linux-* | *-*-k*bsd*-*) fragment < #endif EOF ;; esac fi # Import any needed special functions and/or overrides. # source_em ${srcdir}/emultempl/elf-generic.em if test -n "$EXTRA_EM_FILE" ; then source_em ${srcdir}/emultempl/${EXTRA_EM_FILE}.em fi # Functions in this file can be overridden by setting the LDEMUL_* shell # variables. If the name of the overriding function is the same as is # defined in this file, then don't output this file's version. # If a different overriding name is given then output the standard function # as presumably it is called from the overriding function. # if test x"$LDEMUL_BEFORE_PARSE" != xgld"$EMULATION_NAME"_before_parse; then fragment <as_needed) link_class = DYN_AS_NEEDED; /* Tell the ELF linker that we don't want the output file to have a DT_NEEDED entry for any dynamic library in DT_NEEDED tags from this file at all. */ if (!entry->add_needed) link_class |= DYN_NO_ADD_NEEDED; if (entry->just_syms_flag && (bfd_get_file_flags (entry->the_bfd) & DYNAMIC) != 0) einfo (_("%P%F: --just-symbols may not be used on DSO: %B\n"), entry->the_bfd); if (!link_class || (bfd_get_file_flags (entry->the_bfd) & DYNAMIC) == 0) return FALSE; bfd_elf_set_dyn_lib_class (entry->the_bfd, (enum dynamic_lib_link_class) link_class); /* Continue on with normal load_symbols processing. */ return FALSE; } EOF fi fragment <the_bfd == NULL || (bfd_get_file_flags (s->the_bfd) & DYNAMIC) == 0) return; soname = bfd_elf_get_dt_soname (s->the_bfd); if (soname == NULL) soname = lbasename (bfd_get_filename (s->the_bfd)); for (l = global_vercheck_needed; l != NULL; l = l->next) { const char *suffix; if (strcmp (soname, l->name) == 0) { /* Probably can't happen, but it's an easy check. */ continue; } if (strchr (l->name, '/') != NULL) continue; suffix = strstr (l->name, ".so."); if (suffix == NULL) continue; suffix += sizeof ".so." - 1; if (strncmp (soname, l->name, suffix - l->name) == 0) { /* Here we know that S is a dynamic object FOO.SO.VER1, and the object we are considering needs a dynamic object FOO.SO.VER2, and VER1 and VER2 are different. This appears to be a version mismatch, so we tell the caller to try a different version of this library. */ global_vercheck_failed = 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 (lang_input_statement_type *s) { struct stat st; const char *suffix; const char *soname; if (global_found != NULL) return; if (s->the_bfd == NULL) return; /* If this input file was an as-needed entry, and wasn't found to be needed at the stage it was linked, then don't say we have loaded it. */ if ((bfd_elf_get_dyn_lib_class (s->the_bfd) & DYN_AS_NEEDED) != 0) return; if (bfd_stat (s->the_bfd, &st) != 0) { einfo ("%P:%B: bfd_stat failed: %E\n", s->the_bfd); return; } /* Some operating systems, e.g. Windows, do not provide a meaningful st_ino; they always set it to zero. (Windows does provide a meaningful st_dev.) Do not indicate a duplicate library in that case. While there is no guarantee that a system that provides meaningful inode numbers will never set st_ino to zero, this is merely an optimization, so we do not need to worry about false negatives. */ if (st.st_dev == global_stat.st_dev && st.st_ino == global_stat.st_ino && st.st_ino != 0) { global_found = s; 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 heuristic 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 = lbasename (s->filename); if (strncmp (soname, 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, soname); } struct dt_needed { bfd *by; const char *name; }; /* This function is called for each possible name for a dynamic object named by a DT_NEEDED entry. The FORCE parameter indicates whether to skip the check for a conflicting version. */ static bfd_boolean gld${EMULATION_NAME}_try_needed (struct dt_needed *needed, int force) { bfd *abfd; const char *name = needed->name; const char *soname; int link_class; abfd = bfd_openr (name, bfd_get_target (link_info.output_bfd)); if (abfd == NULL) return FALSE; if (! bfd_check_format (abfd, bfd_object)) { bfd_close (abfd); return FALSE; } if ((bfd_get_file_flags (abfd) & DYNAMIC) == 0) { bfd_close (abfd); return FALSE; } /* For DT_NEEDED, they have to match. */ if (abfd->xvec != link_info.output_bfd->xvec) { bfd_close (abfd); return FALSE; } /* Check whether this object would include any conflicting library versions. If FORCE is set, then we skip this check; we use this the second time around, if we couldn't find any compatible instance of the shared library. */ if (! force) { struct bfd_link_needed_list *needed; if (! bfd_elf_get_bfd_needed_list (abfd, &needed)) einfo ("%F%P:%B: bfd_elf_get_bfd_needed_list failed: %E\n", abfd); if (needed != NULL) { global_vercheck_needed = needed; global_vercheck_failed = FALSE; lang_for_each_input_file (gld${EMULATION_NAME}_vercheck); if (global_vercheck_failed) { bfd_close (abfd); /* Return FALSE to force the caller to move on to try another file on the search path. */ return FALSE; } /* But wait! It gets much worse. On Linux, if a shared library does not use libc at all, we are supposed to skip it the first time around in case we encounter a shared library later on with the same name which does use the version of libc that we want. This is much too horrible to use on any system other than Linux. */ EOF case ${target} in *-*-linux-* | *-*-k*bsd*-*) fragment <next) if (CONST_STRNEQ (l->name, "libc.so")) break; if (l == NULL) { bfd_close (abfd); return FALSE; } } EOF ;; esac fragment <filename); if (trace_file_tries) info_msg (_("found %s at %s\n"), soname, name); global_found = NULL; lang_for_each_input_file (gld${EMULATION_NAME}_stat_needed); if (global_found != NULL) { /* Return TRUE to indicate that we found the file, even though we aren't going to do anything with it. */ return TRUE; } /* Specify the soname to use. */ bfd_elf_set_dt_needed_name (abfd, soname); /* Tell the ELF linker that we don't want the output file to have a DT_NEEDED entry for this file, unless it is used to resolve references in a regular object. */ link_class = DYN_DT_NEEDED; /* Tell the ELF linker that we don't want the output file to have a DT_NEEDED entry for this file at all if the entry is from a file with DYN_NO_ADD_NEEDED. */ if (needed->by != NULL && (bfd_elf_get_dyn_lib_class (needed->by) & DYN_NO_ADD_NEEDED) != 0) link_class |= DYN_NO_NEEDED | DYN_NO_ADD_NEEDED; bfd_elf_set_dyn_lib_class (abfd, (enum dynamic_lib_link_class) link_class); /* 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; } /* Search for a needed file in a path. */ static bfd_boolean gld${EMULATION_NAME}_search_needed (const char *path, struct dt_needed *n, int force) { const char *s; const char *name = n->name; size_t len; struct dt_needed needed; if (name[0] == '/') return gld${EMULATION_NAME}_try_needed (n, force); if (path == NULL || *path == '\0') return FALSE; needed.by = n->by; needed.name = n->name; len = strlen (name); while (1) { char *filename, *sset; s = strchr (path, config.rpath_separator); 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); needed.name = filename; if (gld${EMULATION_NAME}_try_needed (&needed, force)) return TRUE; free (filename); if (*s == '\0') break; path = s + 1; } return FALSE; } EOF if [ "x${USE_LIBPATH}" = xyes ] ; then fragment < #else #include "elf-hints-local.h" #endif static bfd_boolean gld${EMULATION_NAME}_check_ld_elf_hints (const char *name, int force) { static bfd_boolean initialized; static char *ld_elf_hints; struct dt_needed needed; if (!initialized) { FILE *f; char *tmppath; tmppath = concat (ld_sysroot, _PATH_ELF_HINTS, (const char *) NULL); f = fopen (tmppath, FOPEN_RB); free (tmppath); if (f != NULL) { struct elfhints_hdr hdr; if (fread (&hdr, 1, sizeof (hdr), f) == sizeof (hdr) && hdr.magic == ELFHINTS_MAGIC && hdr.version == 1) { if (fseek (f, hdr.strtab + hdr.dirlist, SEEK_SET) != -1) { char *b; b = xmalloc (hdr.dirlistlen + 1); if (fread (b, 1, hdr.dirlistlen + 1, f) == hdr.dirlistlen + 1) ld_elf_hints = gld${EMULATION_NAME}_add_sysroot (b); free (b); } } fclose (f); } initialized = TRUE; } if (ld_elf_hints == NULL) return FALSE; needed.by = NULL; needed.name = name; return gld${EMULATION_NAME}_search_needed (ld_elf_hints, & needed, force); } EOF # FreeBSD ;; *-*-linux-* | *-*-k*bsd*-*) fragment <path == NULL) { info->alloc = p - dir + 1 + 256; info->path = xmalloc (info->alloc); info->len = 0; } else { if (info->len + 1 + (p - dir) >= info->alloc) { info->alloc += p - dir + 256; info->path = xrealloc (info->path, info->alloc); } info->path[info->len++] = config.rpath_separator; } memcpy (info->path + info->len, dir, p - dir); info->len += p - dir; info->path[info->len] = '\0'; } } while (! feof (f)); free (line); fclose (f); return TRUE; } static bfd_boolean gld${EMULATION_NAME}_check_ld_so_conf (const char *name, int force) { static bfd_boolean initialized; static char *ld_so_conf; struct dt_needed needed; if (! initialized) { char *tmppath; struct gld${EMULATION_NAME}_ld_so_conf info; info.path = NULL; info.len = info.alloc = 0; tmppath = concat (ld_sysroot, "${prefix}/etc/ld.so.conf", (const char *) NULL); if (!gld${EMULATION_NAME}_parse_ld_so_conf (&info, tmppath)) { free (tmppath); tmppath = concat (ld_sysroot, "/etc/ld.so.conf", (const char *) NULL); gld${EMULATION_NAME}_parse_ld_so_conf (&info, tmppath); } free (tmppath); if (info.path) { char *d = gld${EMULATION_NAME}_add_sysroot (info.path); free (info.path); ld_so_conf = d; } initialized = TRUE; } if (ld_so_conf == NULL) return FALSE; needed.by = NULL; needed.name = name; return gld${EMULATION_NAME}_search_needed (ld_so_conf, &needed, force); } EOF # Linux ;; esac fi fragment <the_bfd) & DYN_AS_NEEDED) == 0) return; if (s->filename == NULL || s->the_bfd == NULL) return; /* Don't look for a second non-loaded as-needed lib. */ if (global_found != NULL && (bfd_elf_get_dyn_lib_class (s->the_bfd) & DYN_AS_NEEDED) != 0) return; if (strcmp (s->filename, global_needed->name) == 0) { global_found = s; return; } if (s->search_dirs_flag) { const char *f = strrchr (s->filename, '/'); if (f != NULL && strcmp (f + 1, global_needed->name) == 0) { global_found = s; return; } } soname = bfd_elf_get_dt_soname (s->the_bfd); if (soname != NULL && strcmp (soname, global_needed->name) == 0) { global_found = s; return; } } EOF if test x"$LDEMUL_AFTER_OPEN" != xgld"$EMULATION_NAME"_after_open; then fragment <emit_note_gnu_build_id; bfd_size_type size; abfd = abfd; size = offsetof (Elf_External_Note, name[sizeof "GNU"]); size = (size + 3) & -(bfd_size_type) 4; if (!strcmp (style, "md5") || !strcmp (style, "uuid")) size += 128 / 8; else if (!strcmp (style, "sha1")) size += 160 / 8; else if (!strncmp (style, "0x", 2)) { /* ID is in string form (hex). Convert to bits. */ const char *id = style + 2; do { if (ISXDIGIT (id[0]) && ISXDIGIT (id[1])) { ++size; id += 2; } else if (*id == '-' || *id == ':') ++id; else { size = 0; break; } } while (*id != '\0'); } else size = 0; return size; } static unsigned char read_hex (const char xdigit) { if (ISDIGIT (xdigit)) return xdigit - '0'; if (ISUPPER (xdigit)) return xdigit - 'A' + 0xa; if (ISLOWER (xdigit)) return xdigit - 'a' + 0xa; abort (); return 0; } struct build_id_info { const char *style; asection *sec; }; static bfd_boolean gld${EMULATION_NAME}_write_build_id_section (bfd *abfd) { const struct elf_backend_data *bed = get_elf_backend_data (abfd); struct build_id_info *info = (struct build_id_info *) elf_tdata (abfd)->after_write_object_contents_info; asection *asec; Elf_Internal_Shdr *i_shdr; unsigned char *contents, *id_bits; bfd_size_type size; Elf_External_Note *e_note; asec = info->sec; if (bfd_is_abs_section (asec->output_section)) { einfo (_("%P: warning: .note.gnu.build-id section discarded," " --build-id ignored.\n")); return TRUE; } i_shdr = &elf_section_data (asec->output_section)->this_hdr; if (i_shdr->contents == NULL) { if (asec->contents == NULL) asec->contents = (unsigned char *) xmalloc (asec->size); contents = asec->contents; } else contents = i_shdr->contents + asec->output_offset; e_note = (Elf_External_Note *) contents; size = offsetof (Elf_External_Note, name[sizeof "GNU"]); size = (size + 3) & -(bfd_size_type) 4; id_bits = contents + size; size = asec->size - size; bfd_h_put_32 (abfd, sizeof "GNU", &e_note->namesz); bfd_h_put_32 (abfd, size, &e_note->descsz); bfd_h_put_32 (abfd, NT_GNU_BUILD_ID, &e_note->type); memcpy (e_note->name, "GNU", sizeof "GNU"); if (!strcmp (info->style, "md5")) { struct md5_ctx ctx; md5_init_ctx (&ctx); if (bed->s->checksum_contents (abfd, (void (*) (const void *, size_t, void *)) &md5_process_bytes, &ctx)) md5_finish_ctx (&ctx, id_bits); else return FALSE; } else if (!strcmp (info->style, "sha1")) { struct sha1_ctx ctx; sha1_init_ctx (&ctx); if (bed->s->checksum_contents (abfd, (void (*) (const void *, size_t, void *)) &sha1_process_bytes, &ctx)) sha1_finish_ctx (&ctx, id_bits); else return FALSE; } else if (!strcmp (info->style, "uuid")) { int n; int fd = open ("/dev/urandom", O_RDONLY); if (fd < 0) return FALSE; n = read (fd, id_bits, size); close (fd); if (n < (int) size) return FALSE; } else if (!strncmp (info->style, "0x", 2)) { /* ID is in string form (hex). Convert to bits. */ const char *id = info->style + 2; size_t n = 0; do { if (ISXDIGIT (id[0]) && ISXDIGIT (id[1])) { id_bits[n] = read_hex (*id++) << 4; id_bits[n++] |= read_hex (*id++); } else if (*id == '-' || *id == ':') ++id; else abort (); /* Should have been validated earlier. */ } while (*id != '\0'); } else abort (); /* Should have been validated earlier. */ size = asec->size; return (bfd_seek (abfd, i_shdr->sh_offset + asec->output_offset, SEEK_SET) == 0 && bfd_bwrite (contents, size, abfd) == size); } /* This is called after all the input files have been opened. */ static void gld${EMULATION_NAME}_after_open (void) { struct bfd_link_needed_list *needed, *l; struct elf_link_hash_table *htab; htab = elf_hash_table (&link_info); if (!is_elf_hash_table (htab)) return; if (link_info.emit_note_gnu_build_id) { bfd *abfd; asection *s; bfd_size_type size; abfd = link_info.input_bfds; if (abfd == NULL) { /* PR 10555: If there are no input files do not try to create a .note.gnu-build-id section. */ free (link_info.emit_note_gnu_build_id); link_info.emit_note_gnu_build_id = NULL; } else { size = gld${EMULATION_NAME}_id_note_section_size (abfd, &link_info); if (size == 0) { einfo ("%P: warning: unrecognized --build-id style ignored.\n"); free (link_info.emit_note_gnu_build_id); link_info.emit_note_gnu_build_id = NULL; } else { s = bfd_make_section_with_flags (abfd, ".note.gnu.build-id", SEC_ALLOC | SEC_LOAD | SEC_IN_MEMORY | SEC_LINKER_CREATED | SEC_READONLY | SEC_DATA); if (s != NULL && bfd_set_section_alignment (abfd, s, 2)) { struct elf_obj_tdata *t = elf_tdata (link_info.output_bfd); struct build_id_info *b = (struct build_id_info *) xmalloc (sizeof *b); b->style = link_info.emit_note_gnu_build_id; b->sec = s; elf_section_type (s) = SHT_NOTE; s->size = size; t->after_write_object_contents = &gld${EMULATION_NAME}_write_build_id_section; t->after_write_object_contents_info = b; } else { einfo ("%P: warning: Cannot create .note.gnu.build-id section," " --build-id ignored.\n"); free (link_info.emit_note_gnu_build_id); link_info.emit_note_gnu_build_id = NULL; } } } } if (link_info.relocatable) return; if (link_info.eh_frame_hdr && !link_info.traditional_format) { bfd *abfd; asection *s; for (abfd = link_info.input_bfds; abfd; abfd = abfd->link_next) { s = bfd_get_section_by_name (abfd, ".eh_frame"); if (s && s->size > 8 && !bfd_is_abs_section (s->output_section)) break; } if (abfd) { const struct elf_backend_data *bed; bed = get_elf_backend_data (abfd); s = bfd_make_section_with_flags (abfd, ".eh_frame_hdr", bed->dynamic_sec_flags | SEC_READONLY); if (s != NULL && bfd_set_section_alignment (abfd, s, 2)) htab->eh_info.hdr_sec = s; else einfo ("%P: warning: Cannot create .eh_frame_hdr section," " --eh-frame-hdr ignored.\n"); } } /* Get the list of files which appear in DT_NEEDED entries in dynamic objects included in the link (often there will be none). For each such file, we want to track down the corresponding library, and include the symbol table in the link. This is what the runtime dynamic linker will do. Tracking the files down here permits one dynamic object to include another without requiring special action by the person doing the link. Note that the needed list can actually grow while we are stepping through this loop. */ if (!link_info.executable) return; needed = bfd_elf_get_needed_list (link_info.output_bfd, &link_info); for (l = needed; l != NULL; l = l->next) { struct bfd_link_needed_list *ll; struct dt_needed n, nn; int force; /* If the lib that needs this one was --as-needed and wasn't found to be needed, then this lib isn't needed either. */ if (l->by != NULL && (bfd_elf_get_dyn_lib_class (l->by) & DYN_AS_NEEDED) != 0) continue; /* If we've already seen this file, skip it. */ for (ll = needed; ll != l; ll = ll->next) if ((ll->by == NULL || (bfd_elf_get_dyn_lib_class (ll->by) & DYN_AS_NEEDED) == 0) && 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 = NULL; lang_for_each_input_file (gld${EMULATION_NAME}_check_needed); if (global_found != NULL && (bfd_elf_get_dyn_lib_class (global_found->the_bfd) & DYN_AS_NEEDED) == 0) continue; n.by = l->by; n.name = l->name; nn.by = l->by; if (trace_file_tries) info_msg (_("%s needed by %B\n"), l->name, l->by); /* As-needed libs specified on the command line (or linker script) take priority over libs found in search dirs. */ if (global_found != NULL) { nn.name = global_found->filename; if (gld${EMULATION_NAME}_try_needed (&nn, TRUE)) 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 DT_RPATH/DT_RUNPATH entries (native only), then the linker script LIB_SEARCH_DIRS. We do not search using the -L arguments. We search twice. The first time, we skip objects which may introduce version mismatches. The second time, we force their use. See gld${EMULATION_NAME}_vercheck comment. */ for (force = 0; force < 2; force++) { size_t len; search_dirs_type *search; EOF if [ "x${NATIVE}" = xyes ] ; then fragment <next) { char *tmpname = gld${EMULATION_NAME}_add_sysroot (rp->name); found = (rp->by == l->by && gld${EMULATION_NAME}_search_needed (tmpname, &n, force)); free (tmpname); } if (found) break; EOF fi if [ "x${USE_LIBPATH}" = xyes ] ; then case ${target} in *-*-freebsd* | *-*-dragonfly*) fragment <name, force)) break; EOF # FreeBSD ;; *-*-linux-* | *-*-k*bsd*-*) # Linux fragment <name, force)) break; EOF ;; esac fi fragment <name); for (search = search_head; search != NULL; search = search->next) { char *filename; if (search->cmdline) continue; filename = (char *) xmalloc (strlen (search->name) + len + 2); sprintf (filename, "%s/%s", search->name, l->name); nn.name = filename; if (gld${EMULATION_NAME}_try_needed (&nn, force)) break; free (filename); } if (search != NULL) break; EOF fragment <name, l->by); } } EOF fi fragment <type.node_class) { case etree_provide: provide = TRUE; /* Fall thru */ case etree_assign: /* 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. */ if (strcmp (exp->assign.dst, ".") != 0) { if (!bfd_elf_record_link_assignment (link_info.output_bfd, &link_info, exp->assign.dst, provide, exp->assign.hidden)) einfo ("%P%F: failed to record assignment to %s: %E\n", exp->assign.dst); } gld${EMULATION_NAME}_find_exp_assignment (exp->assign.src); break; case etree_binary: gld${EMULATION_NAME}_find_exp_assignment (exp->binary.lhs); gld${EMULATION_NAME}_find_exp_assignment (exp->binary.rhs); break; case etree_trinary: gld${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; case etree_unary: gld${EMULATION_NAME}_find_exp_assignment (exp->unary.child); break; default: break; } } /* This is called by the before_allocation routine via lang_for_each_statement. It locates any assignment statements, and tells the ELF backend about them, in case they are assignments to symbols which are referred to by dynamic objects. */ static void gld${EMULATION_NAME}_find_statement_assignment (lang_statement_union_type *s) { if (s->header.type == lang_assignment_statement_enum) gld${EMULATION_NAME}_find_exp_assignment (s->assignment_statement.exp); } EOF if test x"$LDEMUL_BEFORE_ALLOCATION" != xgld"$EMULATION_NAME"_before_allocation; then if test x"${ELF_INTERPRETER_NAME+set}" = xset; then ELF_INTERPRETER_SET_DEFAULT=" if (sinterp != NULL) { sinterp->contents = (unsigned char *) ${ELF_INTERPRETER_NAME}; sinterp->size = strlen ((char *) sinterp->contents) + 1; } " else ELF_INTERPRETER_SET_DEFAULT= fi fragment <type == bfd_link_elf_hash_table) _bfd_elf_tls_setup (link_info.output_bfd, &link_info); /* If we are going to make any variable assignments, we need to let the ELF backend know about them in case the variables are referred to by dynamic objects. */ lang_for_each_statement (gld${EMULATION_NAME}_find_statement_assignment); /* Let the ELF backend work out the sizes of any sections required by dynamic linking. */ rpath = command_line.rpath; if (rpath == NULL) rpath = (const char *) getenv ("LD_RUN_PATH"); if (! (bfd_elf_size_dynamic_sections (link_info.output_bfd, command_line.soname, rpath, command_line.filter_shlib, (const char * const *) command_line.auxiliary_filters, &link_info, &sinterp, lang_elf_version_info))) einfo ("%P%F: failed to set dynamic section sizes: %E\n"); ${ELF_INTERPRETER_SET_DEFAULT} /* Let the user override the dynamic linker we are using. */ if (command_line.interpreter != NULL && sinterp != NULL) { sinterp->contents = (bfd_byte *) command_line.interpreter; sinterp->size = strlen (command_line.interpreter) + 1; } /* Look for any sections named .gnu.warning. As a GNU extensions, we treat such sections as containing warning messages. We print out the warning message, and then zero out the section size so that it does not get copied into the output file. */ { LANG_FOR_EACH_INPUT_STATEMENT (is) { asection *s; bfd_size_type sz; char *msg; bfd_boolean ret; if (is->just_syms_flag) continue; s = bfd_get_section_by_name (is->the_bfd, ".gnu.warning"); if (s == NULL) continue; sz = s->size; msg = (char *) xmalloc ((size_t) (sz + 1)); if (! bfd_get_section_contents (is->the_bfd, s, msg, (file_ptr) 0, sz)) einfo ("%F%B: Can't read contents of section .gnu.warning: %E\n", is->the_bfd); msg[sz] = '\0'; ret = link_info.callbacks->warning (&link_info, msg, (const char *) NULL, is->the_bfd, (asection *) NULL, (bfd_vma) 0); ASSERT (ret); free (msg); /* Clobber the section size, so that we don't waste space copying the warning into the output file. If we've already sized the output section, adjust its size. The adjustment is on rawsize because targets that size sections early will have called lang_reset_memory_regions after sizing. */ if (s->output_section != NULL && s->output_section->rawsize >= s->size) s->output_section->rawsize -= s->size; s->size = 0; /* Also set SEC_EXCLUDE, so that local symbols defined in the warning section don't get copied to the output. */ s->flags |= SEC_EXCLUDE | SEC_KEEP; } } before_allocation_default (); if (!bfd_elf_size_dynsym_hash_dynstr (link_info.output_bfd, &link_info)) einfo ("%P%F: failed to set dynamic section sizes: %E\n"); } EOF fi if test x"$LDEMUL_OPEN_DYNAMIC_ARCHIVE" != xgld"$EMULATION_NAME"_open_dynamic_archive; then fragment <is_archive) return FALSE; filename = entry->filename; /* This allocates a few bytes too many when EXTRA_SHLIB_EXTENSION is defined, but it does not seem worth the headache to optimize away those two bytes of space. */ string = (char *) xmalloc (strlen (search->name) + strlen (filename) + strlen (arch) #ifdef EXTRA_SHLIB_EXTENSION + strlen (EXTRA_SHLIB_EXTENSION) #endif + sizeof "/lib.so"); sprintf (string, "%s/lib%s%s.so", search->name, filename, arch); #ifdef EXTRA_SHLIB_EXTENSION /* Try the .so extension first. If that fails build a new filename using EXTRA_SHLIB_EXTENSION. */ if (! ldfile_try_open_bfd (string, entry)) { sprintf (string, "%s/lib%s%s%s", search->name, filename, arch, EXTRA_SHLIB_EXTENSION); #endif if (! ldfile_try_open_bfd (string, entry)) { free (string); return FALSE; } #ifdef EXTRA_SHLIB_EXTENSION } #endif entry->filename = string; /* We have found a dynamic object to include in the link. The ELF backend linker will create a DT_NEEDED entry in the .dynamic section naming this file. If this file includes a DT_SONAME entry, it will be used. Otherwise, the ELF linker will just use the name of the file. For an archive found by searching, like this one, the DT_NEEDED entry should consist of just the name of the file, without the path information used to find it. Note that we only need to do this if we have a dynamic object; an archive will never be referenced by a DT_NEEDED entry. FIXME: This approach--using bfd_elf_set_dt_needed_name--is not very pretty. I haven't been able to think of anything that is pretty, though. */ if (bfd_check_format (entry->the_bfd, bfd_object) && (entry->the_bfd->flags & DYNAMIC) != 0) { ASSERT (entry->is_archive && entry->search_dirs_flag); /* Rather than duplicating the logic above. Just use the filename we recorded earlier. */ filename = lbasename (entry->filename); bfd_elf_set_dt_needed_name (entry->the_bfd, filename); } return TRUE; } EOF fi if test x"$LDEMUL_PLACE_ORPHAN" != xgld"$EMULATION_NAME"_place_orphan; then fragment <name[4] == 'a'; for (lookup = &lang_output_section_statement.head->output_section_statement; lookup != NULL; lookup = lookup->next) { if (lookup->constraint >= 0 && CONST_STRNEQ (lookup->name, ".rel")) { int lookrela = lookup->name[4] == 'a'; /* .rel.dyn must come before all other reloc sections, to suit GNU ld.so. */ if (isdyn) break; /* Don't place after .rel.plt as doing so results in wrong dynamic tags. */ if (strcmp (".plt", lookup->name + 4 + lookrela) == 0) break; if (rela == lookrela || last_rel == NULL) last_rel = lookup; if ((rela == lookrela || last_rel_alloc == NULL) && lookup->bfd_section != NULL && (lookup->bfd_section->flags & SEC_ALLOC) != 0) last_rel_alloc = lookup; } last = lookup; if (lookup->bfd_section != NULL && (lookup->bfd_section->flags & SEC_ALLOC) != 0) { last_alloc = lookup; if ((lookup->bfd_section->flags & SEC_READONLY) != 0) last_ro_alloc = lookup; } } if (last_rel_alloc) return last_rel_alloc; if (last_rel) return last_rel; if (last_ro_alloc) return last_ro_alloc; if (last_alloc) return last_alloc; return last; } /* Place an orphan section. We use this to put random SHF_ALLOC sections in the right segment. */ static lang_output_section_statement_type * gld${EMULATION_NAME}_place_orphan (asection *s, const char *secname, int constraint) { static struct orphan_save hold[] = { { ".text", SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE, 0, 0, 0, 0 }, { ".rodata", SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_DATA, 0, 0, 0, 0 }, { ".data", SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_DATA, 0, 0, 0, 0 }, { ".bss", SEC_ALLOC, 0, 0, 0, 0 }, { 0, SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_DATA, 0, 0, 0, 0 }, { ".interp", SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_DATA, 0, 0, 0, 0 }, { ".sdata", SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_SMALL_DATA, 0, 0, 0, 0 }, { 0, SEC_HAS_CONTENTS, 0, 0, 0, 0 }, }; enum orphan_save_index { orphan_text = 0, orphan_rodata, orphan_data, orphan_bss, orphan_rel, orphan_interp, orphan_sdata, orphan_nonalloc }; static int orphan_init_done = 0; struct orphan_save *place; lang_output_section_statement_type *after; lang_output_section_statement_type *os; int isdyn = 0; int iself = s->owner->xvec->flavour == bfd_target_elf_flavour; unsigned int sh_type = iself ? elf_section_type (s) : SHT_NULL; if (! link_info.relocatable && link_info.combreloc && (s->flags & SEC_ALLOC)) { if (iself) switch (sh_type) { case SHT_RELA: secname = ".rela.dyn"; isdyn = 1; break; case SHT_REL: secname = ".rel.dyn"; isdyn = 1; break; default: break; } else if (CONST_STRNEQ (secname, ".rel")) { secname = secname[4] == 'a' ? ".rela.dyn" : ".rel.dyn"; isdyn = 1; } } /* Look through the script to see where to place this section. */ if (constraint == 0) for (os = lang_output_section_find (secname); os != NULL; os = next_matching_output_section_statement (os, 0)) { /* If we don't match an existing output section, tell lang_insert_orphan to create a new output section. */ constraint = SPECIAL; if (os->bfd_section != NULL && (os->bfd_section->flags == 0 || (_bfd_elf_match_sections_by_type (link_info.output_bfd, os->bfd_section, s->owner, s) && ((s->flags ^ os->bfd_section->flags) & (SEC_LOAD | SEC_ALLOC)) == 0))) { /* We already have an output section statement with this name, and its bfd section has compatible flags. If the section already exists but does not have any flags set, then it has been created by the linker, probably as a result of a --section-start command line switch. */ lang_add_section (&os->children, s, os); return os; } } if (!orphan_init_done) { lang_output_section_statement_type *lookup; struct orphan_save *ho; for (ho = hold; ho < hold + sizeof (hold) / sizeof (hold[0]); ++ho) if (ho->name != NULL) { ho->os = lang_output_section_find (ho->name); if (ho->os != NULL && ho->os->flags == 0) ho->os->flags = ho->flags; } lookup = hold[orphan_bss].os; if (lookup == NULL) lookup = &lang_output_section_statement.head->output_section_statement; for (; lookup != NULL; lookup = lookup->next) if ((lookup->bfd_section != NULL && (lookup->bfd_section->flags & SEC_DEBUGGING) != 0) || strcmp (lookup->name, ".comment") == 0) break; hold[orphan_nonalloc].os = lookup ? lookup->prev : NULL; hold[orphan_nonalloc].name = ".comment"; orphan_init_done = 1; } /* 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.executable && ! link_info.relocatable && CONST_STRNEQ (s->name, ".gnu.warning.") && hold[orphan_text].os != NULL) { os = hold[orphan_text].os; lang_add_section (&os->children, s, os); return os; } /* Decide which segment the section should go in based on the section name and section flags. We put loadable .note sections right after the .interp section, so that the PT_NOTE segment is stored right after the program headers where the OS can read it in the first page. */ place = NULL; if ((s->flags & (SEC_ALLOC | SEC_DEBUGGING)) == 0) place = &hold[orphan_nonalloc]; else if ((s->flags & SEC_ALLOC) == 0) ; else if ((s->flags & SEC_LOAD) != 0 && ((iself && sh_type == SHT_NOTE) || (!iself && CONST_STRNEQ (secname, ".note")))) place = &hold[orphan_interp]; else if ((s->flags & (SEC_LOAD | SEC_HAS_CONTENTS)) == 0) place = &hold[orphan_bss]; else if ((s->flags & SEC_SMALL_DATA) != 0) place = &hold[orphan_sdata]; else if ((s->flags & SEC_READONLY) == 0) place = &hold[orphan_data]; else if (((iself && (sh_type == SHT_RELA || sh_type == SHT_REL)) || (!iself && CONST_STRNEQ (secname, ".rel"))) && (s->flags & SEC_LOAD) != 0) place = &hold[orphan_rel]; else if ((s->flags & SEC_CODE) == 0) place = &hold[orphan_rodata]; else place = &hold[orphan_text]; after = NULL; if (place != NULL) { if (place->os == NULL) { if (place->name != NULL) place->os = lang_output_section_find (place->name); else place->os = output_rel_find (s, isdyn); } after = place->os; if (after == NULL) after = lang_output_section_find_by_flags (s, &place->os, _bfd_elf_match_sections_by_type); if (after == NULL) /* *ABS* is always the first output section statement. */ after = &lang_output_section_statement.head->output_section_statement; } return lang_insert_orphan (s, secname, constraint, after, place, NULL, NULL); } EOF fi if test x"$LDEMUL_AFTER_ALLOCATION" != xgld"$EMULATION_NAME"_after_allocation; then fragment <> e${EMULATION_NAME}.c echo ' ; else if (link_info.relocatable) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xr >> e${EMULATION_NAME}.c echo ' ; else if (!config.text_read_only) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xbn >> e${EMULATION_NAME}.c if cmp -s ldscripts/${EMULATION_NAME}.x ldscripts/${EMULATION_NAME}.xn; then : ; else echo ' ; else if (!config.magic_demand_paged) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xn >> e${EMULATION_NAME}.c fi if test -n "$GENERATE_PIE_SCRIPT" ; then if test -n "$GENERATE_COMBRELOC_SCRIPT" ; then echo ' ; else if (link_info.pie && link_info.combreloc' >> e${EMULATION_NAME}.c echo ' && link_info.relro' >> e${EMULATION_NAME}.c echo ' && (link_info.flags & DF_BIND_NOW)) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xdw >> e${EMULATION_NAME}.c echo ' ; else if (link_info.pie && link_info.combreloc) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xdc >> e${EMULATION_NAME}.c fi echo ' ; else if (link_info.pie) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xd >> e${EMULATION_NAME}.c fi if test -n "$GENERATE_SHLIB_SCRIPT" ; then if test -n "$GENERATE_COMBRELOC_SCRIPT" ; then echo ' ; else if (link_info.shared && link_info.combreloc' >> e${EMULATION_NAME}.c echo ' && link_info.relro' >> e${EMULATION_NAME}.c echo ' && (link_info.flags & DF_BIND_NOW)) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xsw >> e${EMULATION_NAME}.c echo ' ; else if (link_info.shared && link_info.combreloc) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xsc >> e${EMULATION_NAME}.c fi echo ' ; else if (link_info.shared) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xs >> e${EMULATION_NAME}.c fi if test -n "$GENERATE_COMBRELOC_SCRIPT" ; then echo ' ; else if (link_info.combreloc && link_info.relro' >> e${EMULATION_NAME}.c echo ' && (link_info.flags & DF_BIND_NOW)) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xw >> e${EMULATION_NAME}.c echo ' ; else if (link_info.combreloc) return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.xc >> e${EMULATION_NAME}.c fi echo ' ; else return' >> e${EMULATION_NAME}.c sed $sc ldscripts/${EMULATION_NAME}.x >> e${EMULATION_NAME}.c echo '; }' >> e${EMULATION_NAME}.c else # Scripts read from the filesystem. fragment <