From cdd3575c2204443be4e4ad258d61bac6c7f2f337 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Thu, 1 Jul 2004 13:48:53 +0000 Subject: [PATCH] bfd/ * elflink.c (elf_section_ignore_discarded_relocs): Revert last change. Comment. (elf_section_complain_discarded): New function. Handle .gcc_except_table too. (elf_link_input_bfd): Rewrite handling of relocs against symbols in discarded sections. * elf-bfd.h (elf_discarded_section): Protect macro arg. ld/testsuite/ * ld-discard/extern.d: Update. * ld-discard/start.d: Update. * ld-discard/static.d: Update. --- bfd/ChangeLog | 10 ++ bfd/elf-bfd.h | 4 +- bfd/elflink.c | 164 +++++++++++++++++-------------- ld/testsuite/ChangeLog | 6 ++ ld/testsuite/ld-discard/extern.d | 2 +- ld/testsuite/ld-discard/start.d | 2 +- ld/testsuite/ld-discard/static.d | 2 +- 7 files changed, 109 insertions(+), 81 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 11bed97504e..c00435ad412 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,13 @@ +2004-07-01 Alan Modra + + * elflink.c (elf_section_ignore_discarded_relocs): Revert last + change. Comment. + (elf_section_complain_discarded): New function. Handle + .gcc_except_table too. + (elf_link_input_bfd): Rewrite handling of relocs against symbols + in discarded sections. + * elf-bfd.h (elf_discarded_section): Protect macro arg. + 2004-06-30 James E Wilson * elfxx-ia64.c (elfNN_ia64_check_relocs): New local pltoff. Initialize diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h index 532cdb31607..1892cb17420 100644 --- a/bfd/elf-bfd.h +++ b/bfd/elf-bfd.h @@ -1067,8 +1067,8 @@ struct bfd_elf_section_data #define elf_discarded_section(sec) \ (!bfd_is_abs_section (sec) \ && bfd_is_abs_section ((sec)->output_section) \ - && sec->sec_info_type != ELF_INFO_TYPE_MERGE \ - && sec->sec_info_type != ELF_INFO_TYPE_JUST_SYMS) + && (sec)->sec_info_type != ELF_INFO_TYPE_MERGE \ + && (sec)->sec_info_type != ELF_INFO_TYPE_JUST_SYMS) #define get_elf_backend_data(abfd) \ ((const struct elf_backend_data *) (abfd)->xvec->backend_data) diff --git a/bfd/elflink.c b/bfd/elflink.c index e682758728c..930438dbeba 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -6258,18 +6258,22 @@ elf_link_output_extsym (struct elf_link_hash_entry *h, void *data) return TRUE; } +/* Return TRUE if special handling is done for relocs in SEC against + symbols defined in discarded sections. */ + static bfd_boolean elf_section_ignore_discarded_relocs (asection *sec) { const struct elf_backend_data *bed; - if (strncmp (".stab", sec->name, 5) == 0 - && (!sec->name[5] || - (sec->name[5] == '.' && ISDIGIT (sec->name[6])))) - return TRUE; - - if (strcmp (".eh_frame", sec->name) == 0) - return TRUE; + switch (sec->sec_info_type) + { + case ELF_INFO_TYPE_STABS: + case ELF_INFO_TYPE_EH_FRAME: + return TRUE; + default: + break; + } bed = get_elf_backend_data (sec->owner); if (bed->elf_backend_ignore_discarded_relocs != NULL @@ -6279,6 +6283,26 @@ elf_section_ignore_discarded_relocs (asection *sec) return FALSE; } +/* Return TRUE if we should complain about a reloc in SEC against a + symbol defined in a discarded section. */ + +static bfd_boolean +elf_section_complain_discarded (asection *sec) +{ + if (strncmp (".stab", sec->name, 5) == 0 + && (!sec->name[5] || + (sec->name[5] == '.' && ISDIGIT (sec->name[6])))) + return FALSE; + + if (strcmp (".eh_frame", sec->name) == 0) + return FALSE; + + if (strcmp (".gcc_except_table", sec->name) == 0) + return FALSE; + + return TRUE; +} + /* Link an input file into the linker output file. This function handles all the sections and relocations of the input file at once. This is so that we only have to read the local symbols once, and @@ -6551,99 +6575,87 @@ elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd) if (!elf_section_ignore_discarded_relocs (o)) { Elf_Internal_Rela *rel, *relend; + bfd_boolean complain = elf_section_complain_discarded (o); rel = internal_relocs; relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel; for ( ; rel < relend; rel++) { unsigned long r_symndx = rel->r_info >> r_sym_shift; - asection *sec; + asection **ps, *sec; + struct elf_link_hash_entry *h = NULL; + const char *sym_name; if (r_symndx >= locsymcount || (elf_bad_symtab (input_bfd) && finfo->sections[r_symndx] == NULL)) { - struct elf_link_hash_entry *h; - h = sym_hashes[r_symndx - extsymoff]; while (h->root.type == bfd_link_hash_indirect || h->root.type == bfd_link_hash_warning) h = (struct elf_link_hash_entry *) h->root.u.i.link; - /* Complain if the definition comes from a - discarded section. */ - sec = h->root.u.def.section; - if ((h->root.type == bfd_link_hash_defined - || h->root.type == bfd_link_hash_defweak) - && elf_discarded_section (sec)) - { - if ((o->flags & SEC_DEBUGGING) != 0) - { - BFD_ASSERT (r_symndx != 0); - /* Try to preserve debug information. */ - if (sec->kept_section != NULL - && sec->size == sec->kept_section->size) - h->root.u.def.section - = sec->kept_section; - else - memset (rel, 0, sizeof (*rel)); - } - else - { - char *r_name - = xstrdup (bfd_archive_filename (o->owner)); - finfo->info->callbacks->error_handler - (LD_DEFINITION_IN_DISCARDED_SECTION, - _("`%T' referenced in section `%s' from %s: discarded in section `%s' from %s\n"), - h->root.root.string, - h->root.root.string, - o->name, r_name, - h->root.u.def.section->name, - bfd_archive_filename (h->root.u.def.section->owner)); - if (r_name) - free (r_name); - } - } + if (h->root.type != bfd_link_hash_defined + && h->root.type != bfd_link_hash_defweak) + continue; + + ps = &h->root.u.def.section; + sym_name = h->root.root.string; } else { - sec = finfo->sections[r_symndx]; + Elf_Internal_Sym *sym = isymbuf + r_symndx; + ps = &finfo->sections[r_symndx]; + sym_name = bfd_elf_local_sym_name (input_bfd, sym); + } - if (sec != NULL && elf_discarded_section (sec)) + /* Complain if the definition comes from a + discarded section. */ + if ((sec = *ps) != NULL && elf_discarded_section (sec)) + { + if ((o->flags & SEC_DEBUGGING) != 0) { - if ((o->flags & SEC_DEBUGGING) != 0) - { - BFD_ASSERT (r_symndx != 0); - /* Try to preserve debug information. */ - if (sec->kept_section != NULL - && sec->size == sec->kept_section->size) - finfo->sections[r_symndx] - = sec->kept_section; - else - { - rel->r_info &= r_type_mask; - rel->r_addend = 0; - } - } - else + BFD_ASSERT (r_symndx != 0); + + /* Try to preserve debug information. + FIXME: This is quite broken. Modifying + the symbol here means we will be changing + all uses of the symbol, not just those in + debug sections. The only thing that makes + this half reasonable is that debug sections + tend to come after other sections. Of + course, that doesn't help with globals. + ??? All link-once sections of the same name + ought to define the same set of symbols, so + it would seem that globals ought to always + be defined in the kept section. */ + if (sec->kept_section != NULL + && sec->size == sec->kept_section->size) { - static int count; - int ok; - char *buf; - - ok = asprintf (&buf, "local symbol %d", - count++); - if (ok <= 0) - buf = (char *) "local symbol"; - finfo->info->callbacks->error_handler - (LD_DEFINITION_IN_DISCARDED_SECTION, - _("`%T' referenced in section `%s': discarded in section `%s' from %s\n"), - buf, buf, o->name, sec->name, - bfd_archive_filename (input_bfd)); - if (ok != -1) - free (buf); + *ps = sec->kept_section; + continue; } } + else if (complain) + { + finfo->info->callbacks->error_handler + (LD_DEFINITION_IN_DISCARDED_SECTION, + _("`%T' referenced in section `%s' of %B: " + "defined in discarded section `%s' of %B\n"), + sym_name, + sym_name, o->name, input_bfd, + sec->name, sec->owner); + } + + /* Remove the symbol reference from the reloc, but + don't kill the reloc completely. This is so that + a zero value will be written into the section, + which may have non-zero contents put there by the + assembler. Zero in things like an eh_frame fde + pc_begin allows stack unwinders to recognize the + fde as bogus. */ + rel->r_info &= r_type_mask; + rel->r_addend = 0; } } } diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog index 3dacd1c710a..5b84ee08ee7 100644 --- a/ld/testsuite/ChangeLog +++ b/ld/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2004-07-01 Alan Modra + + * ld-discard/extern.d: Update. + * ld-discard/start.d: Update. + * ld-discard/static.d: Update. + 2004-06-30 H.J. Lu PR 233 diff --git a/ld/testsuite/ld-discard/extern.d b/ld/testsuite/ld-discard/extern.d index df4c7d1ceab..3409ad44c7a 100644 --- a/ld/testsuite/ld-discard/extern.d +++ b/ld/testsuite/ld-discard/extern.d @@ -1,3 +1,3 @@ #source: extern.s #ld: -T discard.ld -#error: `data' referenced in section `\.text' from tmpdir/dump0.o: discarded in section `\.data\.exit' from tmpdir/dump0.o +#error: `data' referenced in section `\.text' of tmpdir/dump0.o: defined in discarded section `\.data\.exit' of tmpdir/dump0.o diff --git a/ld/testsuite/ld-discard/start.d b/ld/testsuite/ld-discard/start.d index f9885d40f7b..3f91738c526 100644 --- a/ld/testsuite/ld-discard/start.d +++ b/ld/testsuite/ld-discard/start.d @@ -1,4 +1,4 @@ #source: start.s #source: exit.s #ld: -T discard.ld -#error: `data' referenced in section `\.text' from tmpdir/dump0.o: discarded in section `\.data\.exit' from tmpdir/dump1.o +#error: `data' referenced in section `\.text' of tmpdir/dump0.o: defined in discarded section `\.data\.exit' of tmpdir/dump1.o diff --git a/ld/testsuite/ld-discard/static.d b/ld/testsuite/ld-discard/static.d index 1aa44cdd1e0..98ef02f1b15 100644 --- a/ld/testsuite/ld-discard/static.d +++ b/ld/testsuite/ld-discard/static.d @@ -1,3 +1,3 @@ #source: static.s #ld: -T discard.ld -#error: `local symbol 0' referenced in section `\.text': discarded in section `\.data\.exit' from tmpdir/dump0.o +#error: `\.data\.exit' referenced in section `\.text' of tmpdir/dump0.o: defined in discarded section `\.data\.exit' of tmpdir/dump0.o -- 2.30.2