diff options
Diffstat (limited to 'gold/layout.cc')
| -rw-r--r-- | gold/layout.cc | 139 |
1 files changed, 103 insertions, 36 deletions
diff --git a/gold/layout.cc b/gold/layout.cc index af14173..82964ce 100644 --- a/gold/layout.cc +++ b/gold/layout.cc @@ -627,6 +627,18 @@ Layout::get_output_section(const char* name, Stringpool::Key name_key, elfcpp::Elf_Word type, elfcpp::Elf_Xword flags, Output_section_order order, bool is_relro) { + elfcpp::Elf_Word lookup_type = type; + + // For lookup purposes, treat INIT_ARRAY, FINI_ARRAY, and + // PREINIT_ARRAY like PROGBITS. This ensures that we combine + // .init_array, .fini_array, and .preinit_array sections by name + // whatever their type in the input file. We do this because the + // types are not always right in the input files. + if (lookup_type == elfcpp::SHT_INIT_ARRAY + || lookup_type == elfcpp::SHT_FINI_ARRAY + || lookup_type == elfcpp::SHT_PREINIT_ARRAY) + lookup_type = elfcpp::SHT_PROGBITS; + elfcpp::Elf_Xword lookup_flags = flags; // Ignoring SHF_WRITE and SHF_EXECINSTR here means that we combine @@ -635,7 +647,7 @@ Layout::get_output_section(const char* name, Stringpool::Key name_key, // controlling this. lookup_flags &= ~(elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR); - const Key key(name_key, std::make_pair(type, lookup_flags)); + const Key key(name_key, std::make_pair(lookup_type, lookup_flags)); const std::pair<Key, Output_section*> v(key, NULL); std::pair<Section_name_map::iterator, bool> ins( this->section_name_map_.insert(v)); @@ -652,20 +664,24 @@ Layout::get_output_section(const char* name, Stringpool::Key name_key, // there should be an option to control this. Output_section* os = NULL; - if (type == elfcpp::SHT_PROGBITS) + if (lookup_type == elfcpp::SHT_PROGBITS) { if (flags == 0) { Output_section* same_name = this->find_output_section(name); if (same_name != NULL - && same_name->type() == elfcpp::SHT_PROGBITS + && (same_name->type() == elfcpp::SHT_PROGBITS + || same_name->type() == elfcpp::SHT_INIT_ARRAY + || same_name->type() == elfcpp::SHT_FINI_ARRAY + || same_name->type() == elfcpp::SHT_PREINIT_ARRAY) && (same_name->flags() & elfcpp::SHF_TLS) == 0) os = same_name; } else if ((flags & elfcpp::SHF_TLS) == 0) { elfcpp::Elf_Xword zero_flags = 0; - const Key zero_key(name_key, std::make_pair(type, zero_flags)); + const Key zero_key(name_key, std::make_pair(lookup_type, + zero_flags)); Section_name_map::iterator p = this->section_name_map_.find(zero_key); if (p != this->section_name_map_.end()) @@ -815,7 +831,7 @@ Layout::choose_output_section(const Relobj* relobj, const char* name, if (is_input_section && !this->script_options_->saw_sections_clause() && !parameters->options().relocatable()) - name = Layout::output_section_name(name, &len); + name = Layout::output_section_name(relobj, name, &len); Stringpool::Key name_key; name = this->namepool_.add_with_length(name, len, true, &name_key); @@ -884,32 +900,11 @@ Layout::layout(Sized_relobj_file<size, big_endian>* object, unsigned int shndx, if (!this->include_section(object, name, shdr)) return NULL; - Output_section* os; - - // Sometimes .init_array*, .preinit_array* and .fini_array* do not have - // correct section types. Force them here. elfcpp::Elf_Word sh_type = shdr.get_sh_type(); - if (sh_type == elfcpp::SHT_PROGBITS) - { - static const char init_array_prefix[] = ".init_array"; - static const char preinit_array_prefix[] = ".preinit_array"; - static const char fini_array_prefix[] = ".fini_array"; - static size_t init_array_prefix_size = sizeof(init_array_prefix) - 1; - static size_t preinit_array_prefix_size = - sizeof(preinit_array_prefix) - 1; - static size_t fini_array_prefix_size = sizeof(fini_array_prefix) - 1; - - if (strncmp(name, init_array_prefix, init_array_prefix_size) == 0) - sh_type = elfcpp::SHT_INIT_ARRAY; - else if (strncmp(name, preinit_array_prefix, preinit_array_prefix_size) - == 0) - sh_type = elfcpp::SHT_PREINIT_ARRAY; - else if (strncmp(name, fini_array_prefix, fini_array_prefix_size) == 0) - sh_type = elfcpp::SHT_FINI_ARRAY; - } // In a relocatable link a grouped section must not be combined with // any other sections. + Output_section* os; if (parameters->options().relocatable() && (shdr.get_sh_flags() & elfcpp::SHF_GROUP) != 0) { @@ -929,12 +924,18 @@ Layout::layout(Sized_relobj_file<size, big_endian>* object, unsigned int shndx, // By default the GNU linker sorts input sections whose names match // .ctor.*, .dtor.*, .init_array.*, or .fini_array.*. The sections // are sorted by name. This is used to implement constructor - // priority ordering. We are compatible. + // priority ordering. We are compatible. When we put .ctor + // sections in .init_array and .dtor sections in .fini_array, we + // must also sort plain .ctor and .dtor sections. if (!this->script_options_->saw_sections_clause() + && !parameters->options().relocatable() && (is_prefix_of(".ctors.", name) || is_prefix_of(".dtors.", name) || is_prefix_of(".init_array.", name) - || is_prefix_of(".fini_array.", name))) + || is_prefix_of(".fini_array.", name) + || (parameters->options().ctors_in_init_array() + && (strcmp(name, ".ctors") == 0 + || strcmp(name, ".dtors") == 0)))) os->set_must_sort_attached_input_sections(); // FIXME: Handle SHF_LINK_ORDER somewhere. @@ -1256,6 +1257,18 @@ Layout::make_output_section(const char* name, elfcpp::Elf_Word type, } else { + // Sometimes .init_array*, .preinit_array* and .fini_array* do + // not have correct section types. Force them here. + if (type == elfcpp::SHT_PROGBITS) + { + if (is_prefix_of(".init_array", name)) + type = elfcpp::SHT_INIT_ARRAY; + else if (is_prefix_of(".preinit_array", name)) + type = elfcpp::SHT_PREINIT_ARRAY; + else if (is_prefix_of(".fini_array", name)) + type = elfcpp::SHT_FINI_ARRAY; + } + // FIXME: const_cast is ugly. Target* target = const_cast<Target*>(¶meters->target()); os = target->make_output_section(name, type, flags); @@ -1303,10 +1316,12 @@ Layout::make_output_section(const char* name, elfcpp::Elf_Word type, // do the same. We need to know that this might happen before we // attach any input sections. if (!this->script_options_->saw_sections_clause() - && (strcmp(name, ".ctors") == 0 - || strcmp(name, ".dtors") == 0 - || strcmp(name, ".init_array") == 0 - || strcmp(name, ".fini_array") == 0)) + && !parameters->options().relocatable() + && (strcmp(name, ".init_array") == 0 + || strcmp(name, ".fini_array") == 0 + || (!parameters->options().ctors_in_init_array() + && (strcmp(name, ".ctors") == 0 + || strcmp(name, ".dtors") == 0)))) os->set_may_sort_attached_input_sections(); // Check for .stab*str sections, as .stab* sections need to link to @@ -4202,8 +4217,6 @@ Layout::set_dynamic_symbol_size(const Symbol_table* symtab) const Layout::Section_name_mapping Layout::section_name_mapping[] = { MAPPING_INIT(".text.", ".text"), - MAPPING_INIT(".ctors.", ".ctors"), - MAPPING_INIT(".dtors.", ".dtors"), MAPPING_INIT(".rodata.", ".rodata"), MAPPING_INIT(".data.rel.ro.local", ".data.rel.ro.local"), MAPPING_INIT(".data.rel.ro", ".data.rel.ro"), @@ -4255,7 +4268,8 @@ const int Layout::section_name_mapping_count = // length of NAME. const char* -Layout::output_section_name(const char* name, size_t* plen) +Layout::output_section_name(const Relobj* relobj, const char* name, + size_t* plen) { // gcc 4.3 generates the following sorts of section names when it // needs a section name specific to a function: @@ -4302,9 +4316,62 @@ Layout::output_section_name(const char* name, size_t* plen) } } + // As an additional complication, .ctors sections are output in + // either .ctors or .init_array sections, and .dtors sections are + // output in either .dtors or .fini_array sections. + if (is_prefix_of(".ctors.", name) || is_prefix_of(".dtors.", name)) + { + if (parameters->options().ctors_in_init_array()) + { + *plen = 11; + return name[1] == 'c' ? ".init_array" : ".fini_array"; + } + else + { + *plen = 6; + return name[1] == 'c' ? ".ctors" : ".dtors"; + } + } + if (parameters->options().ctors_in_init_array() + && (strcmp(name, ".ctors") == 0 || strcmp(name, ".dtors") == 0)) + { + // To make .init_array/.fini_array work with gcc we must exclude + // .ctors and .dtors sections from the crtbegin and crtend + // files. + if (relobj == NULL + || (!Layout::match_file_name(relobj, "crtbegin") + && !Layout::match_file_name(relobj, "crtend"))) + { + *plen = 11; + return name[1] == 'c' ? ".init_array" : ".fini_array"; + } + } + return name; } +// Return true if RELOBJ is an input file whose base name matches +// FILE_NAME. The base name must have an extension of ".o", and must +// be exactly FILE_NAME.o or FILE_NAME, one character, ".o". This is +// to match crtbegin.o as well as crtbeginS.o without getting confused +// by other possibilities. Overall matching the file name this way is +// a dreadful hack, but the GNU linker does it in order to better +// support gcc, and we need to be compatible. + +bool +Layout::match_file_name(const Relobj* relobj, const char* match) +{ + const std::string& file_name(relobj->name()); + const char* base_name = lbasename(file_name.c_str()); + size_t match_len = strlen(match); + if (strncmp(base_name, match, match_len) != 0) + return false; + size_t base_len = strlen(base_name); + if (base_len != match_len + 2 && base_len != match_len + 3) + return false; + return memcmp(base_name + base_len - 2, ".o", 2) == 0; +} + // Check if a comdat group or .gnu.linkonce section with the given // NAME is selected for the link. If there is already a section, // *KEPT_SECTION is set to point to the existing section and the |