From f37b21b481a7804a13c5806098c19b6119288ba4 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Tue, 23 Jun 2020 12:01:24 -0700 Subject: PR 22843: ld, gold: Add --dependency-file option. gold/ * options.h (class General_options): Add --dependency-file option. * fileread.cc (File_read::files_read): New static variable. (File_read::open): Add the file to the files_read list. (File_read::record_file_read): New static member function. (File_read::write_dependency_file): New static member function. * fileread.h (class File_read): Declare them. * layout.cc (Layout::read_layout_from_file): Call record_file_read. (Close_task_runner::run): Call write_dependency_file if --dependency-file was passed. ld/ * NEWS: Note --dependency-file. * ld.texi (Options): Document --dependency-file. * ldlex.h (enum option_values): Add OPTION_DEPENDENCY_FILE. * ld.h (ld_config_type): New member dependency_file. * lexsup.c (ld_options, parse_args): Parse --dependency-file. * ldmain.c (struct dependency_file): New type. (dependency_files, dependency_files_tail): New static variables. (track_dependency_files): New function. (write_dependency_file): New function. (main): Call it when --dependency-file was passed. * ldfile.c (ldfile_try_open_bfd): Call track_dependency_files. (ldfile_open_command_file_1): Likewise. * ldelf.c (ldelf_try_needed): Likewise. * pe-dll.c (pe_implied_import_dll): Likewise. --- gold/ChangeLog | 13 +++++++++++ gold/fileread.cc | 30 ++++++++++++++++++++++++ gold/fileread.h | 14 +++++++++++- gold/layout.cc | 70 ++++++++++++++++++++++++++++++-------------------------- gold/options.h | 14 ++++++++---- ld/ChangeLog | 18 +++++++++++++++ ld/NEWS | 4 ++++ ld/ld.h | 2 ++ ld/ld.texi | 15 ++++++++++++ ld/ldelf.c | 4 +++- ld/ldfile.c | 28 +++++++++++++---------- ld/ldlex.h | 1 + ld/ldmain.c | 52 ++++++++++++++++++++++++++++++++++++++++- ld/ldmain.h | 1 + ld/lexsup.c | 22 +++++++++++------- ld/pe-dll.c | 2 ++ 16 files changed, 230 insertions(+), 60 deletions(-) diff --git a/gold/ChangeLog b/gold/ChangeLog index f4679f9..4d524d7 100644 --- a/gold/ChangeLog +++ b/gold/ChangeLog @@ -1,3 +1,16 @@ +2020-06-23 Roland McGrath + + PR 22843 + * options.h (class General_options): Add --dependency-file option. + * fileread.cc (File_read::files_read): New static variable. + (File_read::open): Add the file to the files_read list. + (File_read::record_file_read): New static member function. + (File_read::write_dependency_file): New static member function. + * fileread.h (class File_read): Declare them. + * layout.cc (Layout::read_layout_from_file): Call record_file_read. + (Close_task_runner::run): Call write_dependency_file if + --dependency-file was passed. + 2020-06-18 Fangrui Song PR gold/26039 diff --git a/gold/fileread.cc b/gold/fileread.cc index bebe0ab..f5ca719 100644 --- a/gold/fileread.cc +++ b/gold/fileread.cc @@ -124,6 +124,7 @@ static Initialize_lock file_counts_initialize_lock(&file_counts_lock); unsigned long long File_read::total_mapped_bytes; unsigned long long File_read::current_mapped_bytes; unsigned long long File_read::maximum_mapped_bytes; +std::vector File_read::files_read; // Class File_read::View. @@ -211,6 +212,8 @@ File_read::open(const Task* task, const std::string& name) gold_debug(DEBUG_FILES, "Attempt to open %s succeeded", this->name_.c_str()); this->token_.add_writer(task); + Hold_optional_lock hl(file_counts_lock); + record_file_read(this->name_); } return this->descriptor_ >= 0; @@ -1138,4 +1141,31 @@ Input_file::open_binary(const Task* task, const std::string& name) binary_to_elf.converted_size()); } +void +File_read::record_file_read(const std::string& name) +{ + File_read::files_read.push_back(name); +} + +void +File_read::write_dependency_file(const char* dependency_file_name, + const char* output_file_name) +{ + FILE *depfile = fopen(dependency_file_name, "w"); + + fprintf(depfile, "%s:", output_file_name); + for (std::vector::const_iterator it = files_read.begin(); + it != files_read.end(); + ++it) + fprintf(depfile, " \\\n %s", it->c_str()); + fprintf(depfile, "\n"); + + for (std::vector::const_iterator it = files_read.begin(); + it != files_read.end(); + ++it) + fprintf(depfile, "\n%s:\n", it->c_str()); + + fclose(depfile); +} + } // End namespace gold. diff --git a/gold/fileread.h b/gold/fileread.h index cf92367..2120135 100644 --- a/gold/fileread.h +++ b/gold/fileread.h @@ -207,6 +207,15 @@ class File_read static void print_stats(); + // Write the dependency file listing all files read. + static void + write_dependency_file(const char* dependency_file_name, + const char* output_file_name); + + // Record that a file was read. File_read::open does this. + static void + record_file_read(const std::string& name); + // Return the open file descriptor (for plugins). int descriptor() @@ -214,7 +223,7 @@ class File_read this->reopen_descriptor(); return this->descriptor_; } - + // Return the file last modification time. Calls gold_fatal if the stat // system call failed. Timespec @@ -247,6 +256,9 @@ class File_read // --stats. static unsigned long long maximum_mapped_bytes; + // Set of names of all files read. + static std::vector files_read; + // A view into the file. class View { diff --git a/gold/layout.cc b/gold/layout.cc index 0c7be85..13e533a 100644 --- a/gold/layout.cc +++ b/gold/layout.cc @@ -1183,11 +1183,11 @@ Layout::layout(Sized_relobj_file* object, unsigned int shndx, // All ".text.unlikely.*" sections can be moved to a unique // segment with --text-unlikely-segment option. bool text_unlikely_segment - = (parameters->options().text_unlikely_segment() - && is_prefix_of(".text.unlikely", - object->section_name(shndx).c_str())); + = (parameters->options().text_unlikely_segment() + && is_prefix_of(".text.unlikely", + object->section_name(shndx).c_str())); if (text_unlikely_segment) - { + { elfcpp::Elf_Xword flags = this->get_output_section_flags(shdr.get_sh_flags()); @@ -1196,11 +1196,11 @@ Layout::layout(Sized_relobj_file* object, unsigned int shndx, &name_key); os = this->get_output_section(os_name, name_key, sh_type, flags, ORDER_INVALID, false); - // Map this output section to a unique segment. This is done to - // separate "text" that is not likely to be executed from "text" - // that is likely executed. + // Map this output section to a unique segment. This is done to + // separate "text" that is not likely to be executed from "text" + // that is likely executed. os->set_is_unique_segment(); - } + } else { // Plugins can choose to place one or more subsets of sections in @@ -1221,7 +1221,7 @@ Layout::layout(Sized_relobj_file* object, unsigned int shndx, // We know the name of the output section, directly call // get_output_section here by-passing choose_output_section. elfcpp::Elf_Xword flags - = this->get_output_section_flags(shdr.get_sh_flags()); + = this->get_output_section_flags(shdr.get_sh_flags()); const char* os_name = it->second->name; Stringpool::Key name_key; @@ -1229,11 +1229,11 @@ Layout::layout(Sized_relobj_file* object, unsigned int shndx, os = this->get_output_section(os_name, name_key, sh_type, flags, ORDER_INVALID, false); if (!os->is_unique_segment()) - { - os->set_is_unique_segment(); - os->set_extra_segment_flags(it->second->flags); - os->set_segment_alignment(it->second->align); - } + { + os->set_is_unique_segment(); + os->set_extra_segment_flags(it->second->flags); + os->set_segment_alignment(it->second->align); + } } } if (os == NULL) @@ -2268,9 +2268,9 @@ Layout::layout_gnu_property(unsigned int note_type, const int size = parameters->target().get_size(); const bool is_big_endian = parameters->target().is_big_endian(); if (size == 32) - { - if (is_big_endian) - { + { + if (is_big_endian) + { #ifdef HAVE_TARGET_32_BIG parameters->sized_target<32, true>()-> record_gnu_property(note_type, pr_type, pr_datasz, pr_data, @@ -2278,9 +2278,9 @@ Layout::layout_gnu_property(unsigned int note_type, #else gold_unreachable(); #endif - } - else - { + } + else + { #ifdef HAVE_TARGET_32_LITTLE parameters->sized_target<32, false>()-> record_gnu_property(note_type, pr_type, pr_datasz, pr_data, @@ -2288,12 +2288,12 @@ Layout::layout_gnu_property(unsigned int note_type, #else gold_unreachable(); #endif - } - } + } + } else if (size == 64) - { - if (is_big_endian) - { + { + if (is_big_endian) + { #ifdef HAVE_TARGET_64_BIG parameters->sized_target<64, true>()-> record_gnu_property(note_type, pr_type, pr_datasz, pr_data, @@ -2301,9 +2301,9 @@ Layout::layout_gnu_property(unsigned int note_type, #else gold_unreachable(); #endif - } - else - { + } + else + { #ifdef HAVE_TARGET_64_LITTLE parameters->sized_target<64, false>()-> record_gnu_property(note_type, pr_type, pr_datasz, pr_data, @@ -2311,10 +2311,10 @@ Layout::layout_gnu_property(unsigned int note_type, #else gold_unreachable(); #endif - } - } + } + } else - gold_unreachable(); + gold_unreachable(); return; } @@ -2922,6 +2922,8 @@ Layout::read_layout_from_file() gold_fatal(_("unable to open --section-ordering-file file %s: %s"), filename, strerror(errno)); + File_read::record_file_read(filename); + std::getline(in, line); // this chops off the trailing \n, if any unsigned int position = 1; this->set_section_ordering_specified(); @@ -3299,7 +3301,7 @@ Layout::create_gnu_properties_note() write_sized_value(datasz, 4, p + 4, is_big_endian); memcpy(p + 8, prop->second.pr_data, datasz); if (aligned_datasz > datasz) - memset(p + 8 + datasz, 0, aligned_datasz - datasz); + memset(p + 8 + datasz, 0, aligned_datasz - datasz); p += 8 + aligned_datasz; } Output_section_data* posd = new Output_data_const(desc, descsz, 4); @@ -6156,6 +6158,10 @@ Close_task_runner::run(Workqueue*, const Task*) if (this->options_->oformat_enum() != General_options::OBJECT_FORMAT_ELF) this->layout_->write_binary(this->of_); + if (this->options_->dependency_file()) + File_read::write_dependency_file(this->options_->dependency_file(), + this->options_->output_file_name()); + this->of_->close(); } diff --git a/gold/options.h b/gold/options.h index f0e9fbd..3c8d25a 100644 --- a/gold/options.h +++ b/gold/options.h @@ -472,7 +472,7 @@ struct Struct_special : public Struct_var options::String_set::const_iterator \ varname__##_end() const \ { return this->varname__##_.value.end(); } \ - \ + \ options::String_set::size_type \ varname__##_size() const \ { return this->varname__##_.value.size(); } \ @@ -800,6 +800,10 @@ class General_options N_("Do not demangle C++ symbols in log messages"), NULL); + DEFINE_string(dependency_file, options::TWO_DASHES, '\0', NULL, + N_("Write a dependency file listing all files read"), + N_("FILE")); + DEFINE_bool(detect_odr_violations, options::TWO_DASHES, '\0', false, N_("Look for violations of the C++ One Definition Rule"), N_("Do not look for violations of the C++ One Definition Rule")); @@ -1501,10 +1505,10 @@ class General_options DEFINE_uint64(stack_size, options::DASH_Z, '\0', 0, N_("Set PT_GNU_STACK segment p_memsz to SIZE"), N_("SIZE")); DEFINE_enum(start_stop_visibility, options::DASH_Z, '\0', "protected", - N_("ELF symbol visibility for synthesized " - "__start_* and __stop_* symbols"), - ("[default,internal,hidden,protected]"), - {"default", "internal", "hidden", "protected"}); + N_("ELF symbol visibility for synthesized " + "__start_* and __stop_* symbols"), + ("[default,internal,hidden,protected]"), + {"default", "internal", "hidden", "protected"}); DEFINE_bool(text, options::DASH_Z, '\0', false, N_("Do not permit relocations in read-only segments"), N_("Permit relocations in read-only segments")); diff --git a/ld/ChangeLog b/ld/ChangeLog index a2e3f62..7917956 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,21 @@ +2020-06-23 Roland McGrath + + PR 22843 + * NEWS: Note --dependency-file. + * ld.texi (Options): Document --dependency-file. + * ldlex.h (enum option_values): Add OPTION_DEPENDENCY_FILE. + * ld.h (ld_config_type): New member dependency_file. + * lexsup.c (ld_options, parse_args): Parse --dependency-file. + * ldmain.c (struct dependency_file): New type. + (dependency_files, dependency_files_tail): New static variables. + (track_dependency_files): New function. + (write_dependency_file): New function. + (main): Call it when --dependency-file was passed. + * ldfile.c (ldfile_try_open_bfd): Call track_dependency_files. + (ldfile_open_command_file_1): Likewise. + * ldelf.c (ldelf_try_needed): Likewise. + * pe-dll.c (pe_implied_import_dll): Likewise. + 2020-06-23 Alan Modra PR 26150 diff --git a/ld/NEWS b/ld/NEWS index 6955937..4dd4f3c 100644 --- a/ld/NEWS +++ b/ld/NEWS @@ -28,6 +28,10 @@ * Add ELF linker command-line option `-z start-stop-visibility=...' to control the visibility of synthetic `__start_SECNAME` and `__stop_SECNAME` symbols. +* Add command-line option --dependency-file to write a Make-style dependency + file listing the input files consulted by the linker, like the files written + by the compiler's -M -MP options. + Changes in 2.34: * The ld check for "PHDR segment not covered by LOAD segment" is more diff --git a/ld/ld.h b/ld/ld.h index 71fd781..1790dc8 100644 --- a/ld/ld.h +++ b/ld/ld.h @@ -286,6 +286,8 @@ typedef struct char *map_filename; FILE *map_file; + char *dependency_file; + unsigned int split_by_reloc; bfd_size_type split_by_file; diff --git a/ld/ld.texi b/ld/ld.texi index ecdbf77..40b042d 100644 --- a/ld/ld.texi +++ b/ld/ld.texi @@ -893,6 +893,21 @@ Use @var{output} as the name for the program produced by @command{ld}; if this option is not specified, the name @file{a.out} is used by default. The script command @code{OUTPUT} can also specify the output file name. +@kindex --dependency-file=@var{depfile} +@cindex dependency file +@item --dependency-file=@var{depfile} +Write a @dfn{dependency file} to @var{depfile}. This file contains a rule +suitable for @code{make} describing the output file and all the input files +that were read to produce it. The output is similar to the compiler's +output with @samp{-M -MP} (@pxref{Preprocessor Options,, Options +Controlling the Preprocessor, gcc.info, Using the GNU Compiler +Collection}). Note that there is no option like the compiler's @samp{-MM}, +to exclude ``system files'' (which is not a well-specified concept in the +linker, unlike ``system headers'' in the compiler). So the output from +@samp{--dependency-file} is always specific to the exact state of the +installation where it was produced, and should not be copied into +distributed makefiles without careful editing. + @kindex -O @var{level} @cindex generating optimized output @item -O @var{level} diff --git a/ld/ldelf.c b/ld/ldelf.c index 8f2167e..6fa09cf 100644 --- a/ld/ldelf.c +++ b/ld/ldelf.c @@ -262,6 +262,8 @@ ldelf_try_needed (struct dt_needed *needed, int force, int is_linux) return FALSE; } + track_dependency_files (name); + /* Linker needs to decompress sections. */ abfd->flags |= BFD_DECOMPRESS; @@ -1065,7 +1067,7 @@ ldelf_after_open (int use_libpath, int native, int is_linux, int is_freebsd, } return; } - + if (!link_info.traditional_format) { bfd *elfbfd = NULL; diff --git a/ld/ldfile.c b/ld/ldfile.c index f3de2c2..e39170b 100644 --- a/ld/ldfile.c +++ b/ld/ldfile.c @@ -142,6 +142,8 @@ ldfile_try_open_bfd (const char *attempt, return FALSE; } + track_dependency_files (attempt); + /* Linker needs to decompress sections. */ entry->the_bfd->flags |= BFD_DECOMPRESS; @@ -416,21 +418,21 @@ ldfile_open_file (lang_input_statement_type *entry) bfd_boolean found = FALSE; /* If extra_search_path is set, entry->filename is a relative path. - Search the directory of the current linker script before searching - other paths. */ + Search the directory of the current linker script before searching + other paths. */ if (entry->extra_search_path) - { - char *path = concat (entry->extra_search_path, slash, entry->filename, - (const char *)0); - if (ldfile_try_open_bfd (path, entry)) - { - entry->filename = path; - entry->flags.search_dirs = FALSE; - return; - } + { + char *path = concat (entry->extra_search_path, slash, entry->filename, + (const char *)0); + if (ldfile_try_open_bfd (path, entry)) + { + entry->filename = path; + entry->flags.search_dirs = FALSE; + return; + } free (path); - } + } /* Try to open or lib.a. */ for (arch = search_arch_head; arch != NULL; arch = arch->next) @@ -675,6 +677,8 @@ ldfile_open_command_file_1 (const char *name, enum script_open_style open_how) return; } + track_dependency_files (name); + lex_push_file (ldlex_input_stack, name, sysrooted); lineno = 1; diff --git a/ld/ldlex.h b/ld/ldlex.h index 7868dca..5ea083e 100644 --- a/ld/ldlex.h +++ b/ld/ldlex.h @@ -154,6 +154,7 @@ enum option_values OPTION_NO_PRINT_MAP_DISCARDED, OPTION_NON_CONTIGUOUS_REGIONS, OPTION_NON_CONTIGUOUS_REGIONS_WARNINGS, + OPTION_DEPENDENCY_FILE, }; /* The initial parser states. */ diff --git a/ld/ldmain.c b/ld/ldmain.c index 94a745e..08be903 100644 --- a/ld/ldmain.c +++ b/ld/ldmain.c @@ -160,6 +160,53 @@ static bfd_error_handler_type default_bfd_error_handler; struct bfd_link_info link_info; +struct dependency_file +{ + struct dependency_file *next; + char *name; +}; + +static struct dependency_file *dependency_files, *dependency_files_tail; + +void +track_dependency_files (const char *filename) +{ + struct dependency_file *dep + = (struct dependency_file *) xmalloc (sizeof (*dep)); + dep->name = xstrdup (filename); + dep->next = NULL; + if (dependency_files == NULL) + dependency_files = dep; + else + dependency_files_tail->next = dep; + dependency_files_tail = dep; +} + +static void +write_dependency_file (void) +{ + FILE *out; + struct dependency_file *dep; + + out = fopen (config.dependency_file, FOPEN_WT); + if (out == NULL) + { + einfo (_("%F%P: cannot open dependency file %s: %E\n"), + config.dependency_file); + } + + fprintf (out, "%s:", output_filename); + + for (dep = dependency_files; dep != NULL; dep = dep->next) + fprintf (out, " \\\n %s", dep->name); + + fprintf (out, "\n"); + for (dep = dependency_files; dep != NULL; dep = dep->next) + fprintf (out, "\n%s:\n", dep->name); + + fclose (out); +} + static void ld_cleanup (void) { @@ -239,7 +286,7 @@ main (int argc, char **argv) /* is_sysrooted_pathname() relies on no trailing dirsep. */ if (ld_canon_sysroot_len > 0 && IS_DIR_SEPARATOR (ld_canon_sysroot [ld_canon_sysroot_len - 1])) - ld_canon_sysroot [--ld_canon_sysroot_len] = '\0'; + ld_canon_sysroot [--ld_canon_sysroot_len] = '\0'; } else ld_canon_sysroot_len = -1; @@ -481,6 +528,9 @@ main (int argc, char **argv) ldexp_finish (); lang_finish (); + if (config.dependency_file != NULL) + write_dependency_file (); + /* Even if we're producing relocatable output, some non-fatal errors should be reported in the exit status. (What non-fatal errors, if any, do we want to ignore for relocatable output?) */ diff --git a/ld/ldmain.h b/ld/ldmain.h index 0f05821..ac7db57 100644 --- a/ld/ldmain.h +++ b/ld/ldmain.h @@ -58,5 +58,6 @@ extern void add_ysym (const char *); extern void add_wrap (const char *); extern void add_ignoresym (struct bfd_link_info *, const char *); extern void add_keepsyms_file (const char *); +extern void track_dependency_files (const char *); #endif diff --git a/ld/lexsup.c b/ld/lexsup.c index 65a9453..48c6eca 100644 --- a/ld/lexsup.c +++ b/ld/lexsup.c @@ -111,6 +111,8 @@ static const struct ld_option ld_options[] = 'c', N_("FILE"), N_("Read MRI format linker script"), TWO_DASHES }, { {"dc", no_argument, NULL, 'd'}, 'd', NULL, N_("Force common symbols to be defined"), ONE_DASH }, + { {"dependency-file", required_argument, NULL, OPTION_DEPENDENCY_FILE}, + '\0', N_("FILE"), N_("Write dependency file"), TWO_DASHES }, { {"dp", no_argument, NULL, 'd'}, '\0', NULL, NULL, ONE_DASH }, { {"force-group-allocation", no_argument, NULL, @@ -1441,7 +1443,7 @@ parse_args (unsigned argc, char **argv) = lang_new_vers_pattern (NULL, xstrdup (optarg), NULL, FALSE); lang_append_dynamic_list (&export_list, expr); - } + } break; case OPTION_EXPORT_DYNAMIC_SYMBOL_LIST: /* This option indicates a small script that only specifies @@ -1631,6 +1633,10 @@ parse_args (unsigned argc, char **argv) case OPTION_PRINT_MAP_DISCARDED: config.print_map_discarded = TRUE; break; + + case OPTION_DEPENDENCY_FILE: + config.dependency_file = optarg; + break; } } @@ -1906,14 +1912,14 @@ elf_shlib_list_options (FILE *file) } fprintf (file, _("\ -P AUDITLIB, --depaudit=AUDITLIB\n" "\ - Specify a library to use for auditing dependencies\n")); + Specify a library to use for auditing dependencies\n")); fprintf (file, _("\ -z combreloc Merge dynamic relocs into one section and sort\n")); fprintf (file, _("\ -z nocombreloc Don't merge dynamic relocs into one section\n")); fprintf (file, _("\ -z global Make symbols in DSO available for subsequently\n\ - loaded objects\n")); + loaded objects\n")); fprintf (file, _("\ -z initfirst Mark DSO to be initialized first at runtime\n")); fprintf (file, _("\ @@ -1936,7 +1942,7 @@ elf_shlib_list_options (FILE *file) -z now Mark object non-lazy runtime binding\n")); fprintf (file, _("\ -z origin Mark object requiring immediate $ORIGIN\n\ - processing at runtime\n")); + processing at runtime\n")); #if DEFAULT_LD_Z_RELRO fprintf (file, _("\ -z relro Create RELRO program header (default)\n")); @@ -1994,13 +2000,13 @@ elf_static_list_options (FILE *file) --build-id[=STYLE] Generate build ID note\n")); fprintf (file, _("\ --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi]\n\ - Compress DWARF debug sections using zlib\n")); + Compress DWARF debug sections using zlib\n")); #ifdef DEFAULT_FLAG_COMPRESS_DEBUG fprintf (file, _("\ - Default: zlib-gabi\n")); + Default: zlib-gabi\n")); #else fprintf (file, _("\ - Default: none\n")); + Default: none\n")); #endif fprintf (file, _("\ -z common-page-size=SIZE Set common page size to SIZE\n")); @@ -2025,7 +2031,7 @@ elf_plt_unwind_list_options (FILE *file) --ld-generated-unwind-info Generate exception handling info for PLT\n")); fprintf (file, _("\ --no-ld-generated-unwind-info\n\ - Don't generate exception handling info for PLT\n")); + Don't generate exception handling info for PLT\n")); } static void diff --git a/ld/pe-dll.c b/ld/pe-dll.c index f72b658..3e8fe1b 100644 --- a/ld/pe-dll.c +++ b/ld/pe-dll.c @@ -3344,6 +3344,8 @@ pe_implied_import_dll (const char *filename) return FALSE; } + track_dependency_files (filename); + /* PEI dlls seem to be bfd_objects. */ if (!bfd_check_format (dll, bfd_object)) { -- cgit v1.1