diff options
Diffstat (limited to 'bfd/xcofflink.c')
| -rw-r--r-- | bfd/xcofflink.c | 173 |
1 files changed, 123 insertions, 50 deletions
diff --git a/bfd/xcofflink.c b/bfd/xcofflink.c index 3ca9b7287a..da5944eb81 100644 --- a/bfd/xcofflink.c +++ b/bfd/xcofflink.c @@ -2313,6 +2313,97 @@ xcoff_set_import_path (struct bfd_link_info *info, return TRUE; } +/* Return true if the given bfd contains at least one shared object. */ + +static bfd_boolean +xcoff_archive_contains_shared_object_p (bfd *archive) +{ + bfd *member; + + member = bfd_openr_next_archived_file (archive, NULL); + while (member != NULL && (member->flags & DYNAMIC) == 0) + member = bfd_openr_next_archived_file (archive, member); + return member != NULL; +} + +/* Symbol H qualifies for export by -bexpfull. Return true if it also + qualifies for export by -bexpall. */ + +static bfd_boolean +xcoff_covered_by_expall_p (struct xcoff_link_hash_entry *h) +{ + /* Exclude symbols beginning with '_'. */ + if (h->root.root.string[0] == '_') + return FALSE; + + /* Exclude archive members that would otherwise be unreferenced. */ + if ((h->flags & XCOFF_MARK) == 0 + && (h->root.type == bfd_link_hash_defined + || h->root.type == bfd_link_hash_defweak) + && h->root.u.def.section->owner != NULL + && h->root.u.def.section->owner->my_archive != NULL) + return FALSE; + + return TRUE; +} + +/* Return true if symbol H qualifies for the forms of automatic export + specified by AUTO_EXPORT_FLAGS. */ + +static bfd_boolean +xcoff_auto_export_p (struct xcoff_link_hash_entry *h, + unsigned int auto_export_flags) +{ + /* Don't automatically export things that were explicitly exported. */ + if ((h->flags & XCOFF_EXPORT) != 0) + return FALSE; + + /* Don't export things that we don't define. */ + if ((h->flags & XCOFF_DEF_REGULAR) == 0) + return FALSE; + + /* Don't export functions; export their descriptors instead. */ + if (h->root.root.string[0] == '.') + return FALSE; + + /* We don't export a symbol which is being defined by an object + included from an archive which contains a shared object. The + rationale is that if an archive contains both an unshared and + a shared object, then there must be some reason that the + unshared object is unshared, and we don't want to start + providing a shared version of it. In particular, this solves + a bug involving the _savefNN set of functions. gcc will call + those functions without providing a slot to restore the TOC, + so it is essential that these functions be linked in directly + and not from a shared object, which means that a shared + object which also happens to link them in must not export + them. This is confusing, but I haven't been able to think of + a different approach. Note that the symbols can, of course, + be exported explicitly. */ + if (h->root.type == bfd_link_hash_defined + || h->root.type == bfd_link_hash_defweak) + { + bfd *owner; + + owner = h->root.u.def.section->owner; + if (owner != NULL + && owner->my_archive != NULL + && xcoff_archive_contains_shared_object_p (owner->my_archive)) + return FALSE; + } + + /* Otherwise, all symbols are exported by -bexpfull. */ + if ((auto_export_flags & XCOFF_EXPFULL) != 0) + return TRUE; + + /* Despite its name, -bexpall exports most but not all symbols. */ + if ((auto_export_flags & XCOFF_EXPALL) != 0 + && xcoff_covered_by_expall_p (h)) + return TRUE; + + return FALSE; +} + /* Mark a symbol as not being garbage, including the section in which it is defined. */ @@ -2878,6 +2969,24 @@ bfd_xcoff_record_link_assignment (bfd *output_bfd, return TRUE; } +/* An xcoff_link_hash_traverse callback for which DATA points to an + xcoff_loader_info. Mark all symbols that should be automatically + exported. */ + +static bfd_boolean +xcoff_mark_auto_exports (struct xcoff_link_hash_entry *h, void *data) +{ + struct xcoff_loader_info *ldinfo; + + ldinfo = (struct xcoff_loader_info *) data; + if (xcoff_auto_export_p (h, ldinfo->auto_export_flags)) + { + if (!xcoff_mark_symbol (ldinfo->info, h)) + ldinfo->failed = TRUE; + } + return TRUE; +} + /* Add a symbol to the .loader symbols, if necessary. */ /* INPUT_BFD has an external symbol associated with hash table entry H @@ -2939,50 +3048,8 @@ xcoff_build_ldsyms (struct xcoff_link_hash_entry *h, void * p) /* If all defined symbols should be exported, mark them now. We don't want to export the actual functions, just the function descriptors. */ - if (ldinfo->export_defineds - && (h->flags & XCOFF_DEF_REGULAR) != 0 - && h->root.root.string[0] != '.') - { - bfd_boolean export; - - /* We don't export a symbol which is being defined by an object - included from an archive which contains a shared object. The - rationale is that if an archive contains both an unshared and - a shared object, then there must be some reason that the - unshared object is unshared, and we don't want to start - providing a shared version of it. In particular, this solves - a bug involving the _savefNN set of functions. gcc will call - those functions without providing a slot to restore the TOC, - so it is essential that these functions be linked in directly - and not from a shared object, which means that a shared - object which also happens to link them in must not export - them. This is confusing, but I haven't been able to think of - a different approach. Note that the symbols can, of course, - be exported explicitly. */ - export = TRUE; - if ((h->root.type == bfd_link_hash_defined - || h->root.type == bfd_link_hash_defweak) - && h->root.u.def.section->owner != NULL - && h->root.u.def.section->owner->my_archive != NULL) - { - bfd *arbfd, *member; - - arbfd = h->root.u.def.section->owner->my_archive; - member = bfd_openr_next_archived_file (arbfd, NULL); - while (member != NULL) - { - if ((member->flags & DYNAMIC) != 0) - { - export = FALSE; - break; - } - member = bfd_openr_next_archived_file (arbfd, member); - } - } - - if (export) - h->flags |= XCOFF_EXPORT; - } + if (xcoff_auto_export_p (h, ldinfo->auto_export_flags)) + h->flags |= XCOFF_EXPORT; /* We don't want to garbage collect symbols which are not defined in XCOFF files. This is a convenient place to mark them. */ @@ -3181,10 +3248,9 @@ xcoff_keep_symbol_p (struct bfd_link_info *info, bfd *input_bfd, -bmaxdata linker option). GC is whether to do garbage collection (the -bgc linker option). MODTYPE is the module type (the -bmodtype linker option). TEXTRO is whether the text section must - be read only (the -btextro linker option). EXPORT_DEFINEDS is - whether all defined symbols should be exported (the -unix linker - option). SPECIAL_SECTIONS is set by this routine to csects with - magic names like _end. */ + be read only (the -btextro linker option). AUTO_EXPORT_FLAGS + is a mask of XCOFF_EXPALL and XCOFF_EXPFULL. SPECIAL_SECTIONS + is set by this routine to csects with magic names like _end. */ bfd_boolean bfd_xcoff_size_dynamic_sections (bfd *output_bfd, @@ -3197,7 +3263,7 @@ bfd_xcoff_size_dynamic_sections (bfd *output_bfd, bfd_boolean gc, int modtype, bfd_boolean textro, - bfd_boolean export_defineds, + unsigned int auto_export_flags, asection **special_sections, bfd_boolean rtld) { @@ -3225,7 +3291,7 @@ bfd_xcoff_size_dynamic_sections (bfd *output_bfd, ldinfo.failed = FALSE; ldinfo.output_bfd = output_bfd; ldinfo.info = info; - ldinfo.export_defineds = export_defineds; + ldinfo.auto_export_flags = auto_export_flags; ldinfo.ldsym_count = 0; ldinfo.string_size = 0; ldinfo.strings = NULL; @@ -3328,6 +3394,13 @@ bfd_xcoff_size_dynamic_sections (bfd *output_bfd, if (info->fini_function != NULL && !xcoff_mark_symbol_by_name (info, info->fini_function, 0)) goto error_return; + if (auto_export_flags != 0) + { + xcoff_link_hash_traverse (xcoff_hash_table (info), + xcoff_mark_auto_exports, &ldinfo); + if (ldinfo.failed) + goto error_return; + } xcoff_sweep (info); xcoff_hash_table (info)->gc = TRUE; } |
