1 // main.cc -- gold main function. 2 3 // Copyright (C) 2006-2016 Free Software Foundation, Inc. 4 // Written by Ian Lance Taylor <iant@google.com>. 5 6 // This file is part of gold. 7 8 // This program is free software; you can redistribute it and/or modify 9 // it under the terms of the GNU General Public License as published by 10 // the Free Software Foundation; either version 3 of the License, or 11 // (at your option) any later version. 12 13 // This program is distributed in the hope that it will be useful, 14 // but WITHOUT ANY WARRANTY; without even the implied warranty of 15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 // GNU General Public License for more details. 17 18 // You should have received a copy of the GNU General Public License 19 // along with this program; if not, write to the Free Software 20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 // MA 02110-1301, USA. 22 23 #include "gold.h" 24 25 #include <cstdio> 26 #include <cstring> 27 28 #ifdef HAVE_MALLINFO 29 #include <malloc.h> 30 #endif 31 32 #include "libiberty.h" 33 34 #include "script.h" 35 #include "options.h" 36 #include "target-select.h" 37 #include "parameters.h" 38 #include "errors.h" 39 #include "mapfile.h" 40 #include "dirsearch.h" 41 #include "workqueue.h" 42 #include "object.h" 43 #include "archive.h" 44 #include "symtab.h" 45 #include "layout.h" 46 #include "plugin.h" 47 #include "gc.h" 48 #include "icf.h" 49 #include "incremental.h" 50 #include "gdb-index.h" 51 #include "timer.h" 52 53 using namespace gold; 54 55 // This function emits the commandline to a hard-coded file in temp. 56 // This is useful for debugging since ld is typically invoked by gcc, 57 // so its commandline is not always easy to extract. You should be 58 // able to run 'gcc -B... foo.o -o foo' to invoke this linker the 59 // first time, and then /tmp/ld-run-foo.sh to invoke it on subsequent 60 // runes. "/tmp/ld-run-foo.sh debug" will run the linker inside gdb 61 // (or whatever value the environment variable GDB is set to), for 62 // even easier debugging. Since this is a debugging-only tool, and 63 // creates files, it is only turned on when the user explicitly asks 64 // for it, by compiling with -DDEBUG. Do not do this for release 65 // versions of the linker! 66 67 #ifdef DEBUG 68 #include <stdio.h> 69 #include <sys/stat.h> // for chmod() 70 71 static std::string 72 collect_argv(int argc, char** argv) 73 { 74 // This is used by write_debug_script(), which wants the unedited argv. 75 std::string args; 76 for (int i = 0; i < argc; ++i) 77 { 78 args.append(" '"); 79 // Now append argv[i], but with all single-quotes escaped 80 const char* argpos = argv[i]; 81 while (1) 82 { 83 const int len = strcspn(argpos, "'"); 84 args.append(argpos, len); 85 if (argpos[len] == '\0') 86 break; 87 args.append("'\"'\"'"); 88 argpos += len + 1; 89 } 90 args.append("'"); 91 } 92 return args; 93 } 94 95 static void 96 write_debug_script(std::string filename_str, 97 const char* argv_0, const char* args) 98 { 99 size_t slash = filename_str.rfind('/'); 100 if (slash != std::string::npos) 101 filename_str = filename_str.c_str() + slash + 1; 102 filename_str = std::string("/tmp/ld-run-") + filename_str + ".sh"; 103 const char* filename = filename_str.c_str(); 104 FILE* fp = fopen(filename, "w"); 105 if (fp) 106 { 107 fprintf(fp, "[ \"$1\" = debug ]" 108 " && PREFIX=\"${GDB-gdb} --annotate=3 --fullname %s --args\"" 109 " && shift\n", 110 argv_0); 111 fprintf(fp, "$PREFIX%s $*\n", args); 112 fclose(fp); 113 chmod(filename, 0755); 114 } 115 else 116 filename = "[none]"; 117 fprintf(stderr, "Welcome to gold! Commandline written to %s.\n", filename); 118 fflush(stderr); 119 } 120 121 #else // !defined(DEBUG) 122 123 static inline std::string 124 collect_argv(int, char**) 125 { 126 return ""; 127 } 128 129 static inline void 130 write_debug_script(std::string, const char*, const char*) 131 { 132 } 133 134 #endif // !defined(DEBUG) 135 136 137 int 138 main(int argc, char** argv) 139 { 140 #if defined (HAVE_SETLOCALE) && defined (HAVE_LC_MESSAGES) 141 setlocale(LC_MESSAGES, ""); 142 #endif 143 #if defined (HAVE_SETLOCALE) 144 setlocale(LC_CTYPE, ""); 145 #endif 146 bindtextdomain(PACKAGE, LOCALEDIR); 147 textdomain(PACKAGE); 148 149 program_name = argv[0]; 150 151 // In libiberty; expands @filename to the args in "filename". 152 expandargv(&argc, &argv); 153 154 // This is used by write_debug_script(), which wants the unedited argv. 155 std::string args = collect_argv(argc, argv); 156 157 Errors errors(program_name); 158 159 // Initialize the global parameters, to let random code get to the 160 // errors object. 161 set_parameters_errors(&errors); 162 163 // Handle the command line options. 164 Command_line command_line; 165 command_line.process(argc - 1, const_cast<const char**>(argv + 1)); 166 167 Timer timer; 168 if (command_line.options().stats()) 169 { 170 timer.start(); 171 set_parameters_timer(&timer); 172 } 173 174 // Store some options in the globally accessible parameters. 175 set_parameters_options(&command_line.options()); 176 177 // Do this as early as possible (since it prints a welcome message). 178 write_debug_script(command_line.options().output_file_name(), 179 program_name, args.c_str()); 180 181 // If the user asked for a map file, open it. 182 Mapfile* mapfile = NULL; 183 if (command_line.options().user_set_Map()) 184 { 185 mapfile = new Mapfile(); 186 if (!mapfile->open(command_line.options().Map())) 187 { 188 delete mapfile; 189 mapfile = NULL; 190 } 191 } 192 193 // The GNU linker ignores version scripts when generating 194 // relocatable output. If we are not compatible, then we break the 195 // Linux kernel build, which uses a linker script with -r which must 196 // not force symbols to be local. It would actually be useful to 197 // permit symbols to be forced local with -r, though, as it would 198 // permit some linker optimizations. Perhaps we need yet another 199 // option to control this. FIXME. 200 if (parameters->options().relocatable()) 201 command_line.script_options().version_script_info()->clear(); 202 203 // The work queue. 204 Workqueue workqueue(command_line.options()); 205 206 // The list of input objects. 207 Input_objects input_objects; 208 209 // The Garbage Collection (GC, --gc-sections) Object. 210 Garbage_collection gc; 211 212 // The Identical Code Folding (ICF, --icf) Object. 213 Icf icf; 214 215 // The symbol table. We're going to guess here how many symbols 216 // we're going to see based on the number of input files. Even when 217 // this is off, it means at worst we don't quite optimize hashtable 218 // resizing as well as we could have (perhaps using more memory). 219 Symbol_table symtab(command_line.number_of_input_files() * 1024, 220 command_line.version_script()); 221 222 if (parameters->options().gc_sections()) 223 symtab.set_gc(&gc); 224 225 if (parameters->options().icf_enabled()) 226 symtab.set_icf(&icf); 227 228 // The layout object. 229 Layout layout(command_line.number_of_input_files(), 230 &command_line.script_options()); 231 232 if (layout.incremental_inputs() != NULL) 233 layout.incremental_inputs()->report_command_line(argc, argv); 234 235 if (parameters->options().section_ordering_file()) 236 layout.read_layout_from_file(); 237 238 // Load plugin libraries. 239 if (command_line.options().has_plugins()) 240 command_line.options().plugins()->load_plugins(&layout); 241 242 // Get the search path from the -L options. 243 Dirsearch search_path; 244 search_path.initialize(&workqueue, &command_line.options().library_path()); 245 246 // Queue up the first set of tasks. 247 queue_initial_tasks(command_line.options(), search_path, 248 command_line, &workqueue, &input_objects, 249 &symtab, &layout, mapfile); 250 251 // Run the main task processing loop. 252 workqueue.process(0); 253 254 if (command_line.options().print_output_format()) 255 print_output_format(); 256 257 if (command_line.options().stats()) 258 { 259 timer.stamp(2); 260 Timer::TimeStats elapsed = timer.get_pass_time(0); 261 fprintf(stderr, 262 _("%s: initial tasks run time: " \ 263 "(user: %ld.%06ld sys: %ld.%06ld wall: %ld.%06ld)\n"), 264 program_name, 265 elapsed.user / 1000, (elapsed.user % 1000) * 1000, 266 elapsed.sys / 1000, (elapsed.sys % 1000) * 1000, 267 elapsed.wall / 1000, (elapsed.wall % 1000) * 1000); 268 elapsed = timer.get_pass_time(1); 269 fprintf(stderr, 270 _("%s: middle tasks run time: " \ 271 "(user: %ld.%06ld sys: %ld.%06ld wall: %ld.%06ld)\n"), 272 program_name, 273 elapsed.user / 1000, (elapsed.user % 1000) * 1000, 274 elapsed.sys / 1000, (elapsed.sys % 1000) * 1000, 275 elapsed.wall / 1000, (elapsed.wall % 1000) * 1000); 276 elapsed = timer.get_pass_time(2); 277 fprintf(stderr, 278 _("%s: final tasks run time: " \ 279 "(user: %ld.%06ld sys: %ld.%06ld wall: %ld.%06ld)\n"), 280 program_name, 281 elapsed.user / 1000, (elapsed.user % 1000) * 1000, 282 elapsed.sys / 1000, (elapsed.sys % 1000) * 1000, 283 elapsed.wall / 1000, (elapsed.wall % 1000) * 1000); 284 elapsed = timer.get_elapsed_time(); 285 fprintf(stderr, 286 _("%s: total run time: " \ 287 "(user: %ld.%06ld sys: %ld.%06ld wall: %ld.%06ld)\n"), 288 program_name, 289 elapsed.user / 1000, (elapsed.user % 1000) * 1000, 290 elapsed.sys / 1000, (elapsed.sys % 1000) * 1000, 291 elapsed.wall / 1000, (elapsed.wall % 1000) * 1000); 292 293 #ifdef HAVE_MALLINFO 294 struct mallinfo m = mallinfo(); 295 fprintf(stderr, _("%s: total space allocated by malloc: %d bytes\n"), 296 program_name, m.arena); 297 #endif 298 File_read::print_stats(); 299 Archive::print_stats(); 300 Lib_group::print_stats(); 301 fprintf(stderr, _("%s: output file size: %lld bytes\n"), 302 program_name, static_cast<long long>(layout.output_file_size())); 303 symtab.print_stats(); 304 layout.print_stats(); 305 Gdb_index::print_stats(); 306 Free_list::print_stats(); 307 } 308 309 // Issue defined symbol report. 310 if (command_line.options().user_set_print_symbol_counts()) 311 input_objects.print_symbol_counts(&symtab); 312 313 // Output cross reference table. 314 if (command_line.options().cref()) 315 input_objects.print_cref(&symtab, 316 mapfile == NULL ? stdout : mapfile->file()); 317 318 if (mapfile != NULL) 319 mapfile->close(); 320 321 if (parameters->options().fatal_warnings() 322 && errors.warning_count() > 0 323 && errors.error_count() == 0) 324 gold_error("treating warnings as errors"); 325 326 // If the user used --noinhibit-exec, we force the exit status to be 327 // successful. This is compatible with GNU ld. 328 gold_exit((errors.error_count() == 0 329 || parameters->options().noinhibit_exec()) 330 ? GOLD_OK 331 : GOLD_ERR); 332 } 333