gdb/compile/compile.c

   1 /* General Compile and inject code
   2
   3    Copyright (C) 2014-2017 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "top.h"
  22 #include "ui-out.h"
  23 #include "command.h"
  24 #include "cli/cli-script.h"
  25 #include "cli/cli-utils.h"
  26 #include "completer.h"
  27 #include "gdbcmd.h"
  28 #include "compile.h"
  29 #include "compile-internal.h"
  30 #include "compile-object-load.h"
  31 #include "compile-object-run.h"
  32 #include "language.h"
  33 #include "frame.h"
  34 #include "source.h"
  35 #include "block.h"
  36 #include "arch-utils.h"
  37 #include "filestuff.h"
  38 #include "target.h"
  39 #include "osabi.h"
  40 #include "gdb_wait.h"
  41 #include "valprint.h"
  42 #include "common/gdb_optional.h"
  43 #include "common/gdb_unlinker.h"
  44
  45 \f
  46
  47 /* Initial filename for temporary files.  */
  48
  49 #define TMP_PREFIX "/tmp/gdbobj-"
  50
  51 /* Hold "compile" commands.  */
  52
  53 static struct cmd_list_element *compile_command_list;
  54
  55 /* Debug flag for "compile" commands.  */
  56
  57 int compile_debug;
  58
  59 /* Implement "show debug compile".  */
  60
  61 static void
  62 show_compile_debug (struct ui_file *file, int from_tty,
  63                     struct cmd_list_element *c, const char *value)
  64 {
  65   fprintf_filtered (file, _("Compile debugging is %s.\n"), value);
  66 }
  67
  68 \f
  69
  70 /* Check *ARG for a "-raw" or "-r" argument.  Return 0 if not seen.
  71    Return 1 if seen and update *ARG.  */
  72
  73 static int
  74 check_raw_argument (const char **arg)
  75 {
  76   *arg = skip_spaces (*arg);
  77
  78   if (arg != NULL
  79       && (check_for_argument (arg, "-raw", sizeof ("-raw") - 1)
  80           || check_for_argument (arg, "-r", sizeof ("-r") - 1)))
  81       return 1;
  82   return 0;
  83 }
  84
  85 /* Handle the input from the 'compile file' command.  The "compile
  86    file" command is used to evaluate an expression contained in a file
  87    that may contain calls to the GCC compiler.  */
  88
  89 static void
  90 compile_file_command (const char *arg, int from_tty)
  91 {
  92   enum compile_i_scope_types scope = COMPILE_I_SIMPLE_SCOPE;
  93
  94   scoped_restore save_async = make_scoped_restore (&current_ui->async, 0);
  95
  96   /* Check the user did not just <enter> after command.  */
  97   if (arg == NULL)
  98     error (_("You must provide a filename for this command."));
  99
 100   /* Check if a raw (-r|-raw) argument is provided.  */
 101   if (arg != NULL && check_raw_argument (&arg))
 102     {
 103       scope = COMPILE_I_RAW_SCOPE;
 104       arg = skip_spaces (arg);
 105     }
 106
 107   /* After processing arguments, check there is a filename at the end
 108      of the command.  */
 109   if (arg[0] == '\0')
 110     error (_("You must provide a filename with the raw option set."));
 111
 112   if (arg[0] == '-')
 113     error (_("Unknown argument specified."));
 114
 115   arg = skip_spaces (arg);
 116   gdb::unique_xmalloc_ptr<char> abspath = gdb_abspath (arg);
 117   std::string buffer = string_printf ("#include \"%s\"\n", abspath.get ());
 118   eval_compile_command (NULL, buffer.c_str (), scope, NULL);
 119 }
 120
 121 /* Handle the input from the 'compile code' command.  The
 122    "compile code" command is used to evaluate an expression that may
 123    contain calls to the GCC compiler.  The language expected in this
 124    compile command is the language currently set in GDB.  */
 125
 126 static void
 127 compile_code_command (const char *arg, int from_tty)
 128 {
 129   enum compile_i_scope_types scope = COMPILE_I_SIMPLE_SCOPE;
 130
 131   scoped_restore save_async = make_scoped_restore (&current_ui->async, 0);
 132
 133   if (arg != NULL && check_raw_argument (&arg))
 134     {
 135       scope = COMPILE_I_RAW_SCOPE;
 136       arg = skip_spaces (arg);
 137     }
 138
 139   arg = skip_spaces (arg);
 140
 141   if (arg != NULL && !check_for_argument (&arg, "--", sizeof ("--") - 1))
 142     {
 143       if (arg[0] == '-')
 144         error (_("Unknown argument specified."));
 145     }
 146
 147   if (arg && *arg)
 148     eval_compile_command (NULL, arg, scope, NULL);
 149   else
 150     {
 151       command_line_up l = get_command_line (compile_control, "");
 152
 153       l->control_u.compile.scope = scope;
 154       execute_control_command_untraced (l.get ());
 155     }
 156 }
 157
 158 /* Callback for compile_print_command.  */
 159
 160 void
 161 compile_print_value (struct value *val, void *data_voidp)
 162 {
 163   const struct format_data *fmtp = (const struct format_data *) data_voidp;
 164
 165   print_value (val, fmtp);
 166 }
 167
 168 /* Handle the input from the 'compile print' command.  The "compile
 169    print" command is used to evaluate and print an expression that may
 170    contain calls to the GCC compiler.  The language expected in this
 171    compile command is the language currently set in GDB.  */
 172
 173 static void
 174 compile_print_command (const char *arg, int from_tty)
 175 {
 176   enum compile_i_scope_types scope = COMPILE_I_PRINT_ADDRESS_SCOPE;
 177   struct format_data fmt;
 178
 179   scoped_restore save_async = make_scoped_restore (&current_ui->async, 0);
 180
 181   /* Passing &FMT as SCOPE_DATA is safe as do_module_cleanup will not
 182      touch the stale pointer if compile_object_run has already quit.  */
 183   print_command_parse_format (&arg, "compile print", &fmt);
 184
 185   if (arg && *arg)
 186     eval_compile_command (NULL, arg, scope, &fmt);
 187   else
 188     {
 189       command_line_up l = get_command_line (compile_control, "");
 190
 191       l->control_u.compile.scope = scope;
 192       l->control_u.compile.scope_data = &fmt;
 193       execute_control_command_untraced (l.get ());
 194     }
 195 }
 196
 197 /* A cleanup function to remove a directory and all its contents.  */
 198
 199 static void
 200 do_rmdir (void *arg)
 201 {
 202   const char *dir = (const char *) arg;
 203   char *zap;
 204   int wstat;
 205
 206   gdb_assert (startswith (dir, TMP_PREFIX));
 207   zap = concat ("rm -rf ", dir, (char *) NULL);
 208   wstat = system (zap);
 209   if (wstat == -1 || !WIFEXITED (wstat) || WEXITSTATUS (wstat) != 0)
 210     warning (_("Could not remove temporary directory %s"), dir);
 211   XDELETEVEC (zap);
 212 }
 213
 214 /* Return the name of the temporary directory to use for .o files, and
 215    arrange for the directory to be removed at shutdown.  */
 216
 217 static const char *
 218 get_compile_file_tempdir (void)
 219 {
 220   static char *tempdir_name;
 221
 222 #define TEMPLATE TMP_PREFIX "XXXXXX"
 223   char tname[sizeof (TEMPLATE)];
 224
 225   if (tempdir_name != NULL)
 226     return tempdir_name;
 227
 228   strcpy (tname, TEMPLATE);
 229 #undef TEMPLATE
 230 #ifdef HAVE_MKDTEMP
 231   tempdir_name = mkdtemp (tname);
 232 #else
 233   error (_("Command not supported on this host."));
 234 #endif
 235   if (tempdir_name == NULL)
 236     perror_with_name (_("Could not make temporary directory"));
 237
 238   tempdir_name = xstrdup (tempdir_name);
 239   make_final_cleanup (do_rmdir, tempdir_name);
 240   return tempdir_name;
 241 }
 242
 243 /* Compute the names of source and object files to use.  */
 244
 245 static compile_file_names
 246 get_new_file_names ()
 247 {
 248   static int seq;
 249   const char *dir = get_compile_file_tempdir ();
 250
 251   ++seq;
 252
 253   return compile_file_names (string_printf ("%s%sout%d.c",
 254                                             dir, SLASH_STRING, seq),
 255                              string_printf ("%s%sout%d.o",
 256                                             dir, SLASH_STRING, seq));
 257 }
 258
 259 /* Get the block and PC at which to evaluate an expression.  */
 260
 261 static const struct block *
 262 get_expr_block_and_pc (CORE_ADDR *pc)
 263 {
 264   const struct block *block = get_selected_block (pc);
 265
 266   if (block == NULL)
 267     {
 268       struct symtab_and_line cursal = get_current_source_symtab_and_line ();
 269
 270       if (cursal.symtab)
 271         block = BLOCKVECTOR_BLOCK (SYMTAB_BLOCKVECTOR (cursal.symtab),
 272                                    STATIC_BLOCK);
 273       if (block != NULL)
 274         *pc = BLOCK_START (block);
 275     }
 276   else
 277     *pc = BLOCK_START (block);
 278
 279   return block;
 280 }
 281
 282 /* Call buildargv (via gdb_argv), set its result for S into *ARGVP but
 283    calculate also the number of parsed arguments into *ARGCP.  If
 284    buildargv has returned NULL then *ARGCP is set to zero.  */
 285
 286 static void
 287 build_argc_argv (const char *s, int *argcp, char ***argvp)
 288 {
 289   gdb_argv args (s);
 290
 291   *argcp = args.count ();
 292   *argvp = args.release ();
 293 }
 294
 295 /* String for 'set compile-args' and 'show compile-args'.  */
 296 static char *compile_args;
 297
 298 /* Parsed form of COMPILE_ARGS.  COMPILE_ARGS_ARGV is NULL terminated.  */
 299 static int compile_args_argc;
 300 static char **compile_args_argv;
 301
 302 /* Implement 'set compile-args'.  */
 303
 304 static void
 305 set_compile_args (char *args, int from_tty, struct cmd_list_element *c)
 306 {
 307   freeargv (compile_args_argv);
 308   build_argc_argv (compile_args, &compile_args_argc, &compile_args_argv);
 309 }
 310
 311 /* Implement 'show compile-args'.  */
 312
 313 static void
 314 show_compile_args (struct ui_file *file, int from_tty,
 315                    struct cmd_list_element *c, const char *value)
 316 {
 317   fprintf_filtered (file, _("Compile command command-line arguments "
 318                             "are \"%s\".\n"),
 319                     value);
 320 }
 321
 322 /* Append ARGC and ARGV (as parsed by build_argc_argv) to *ARGCP and *ARGVP.
 323    ARGCP+ARGVP can be zero+NULL and also ARGC+ARGV can be zero+NULL.  */
 324
 325 static void
 326 append_args (int *argcp, char ***argvp, int argc, char **argv)
 327 {
 328   int argi;
 329
 330   *argvp = XRESIZEVEC (char *, *argvp, (*argcp + argc + 1));
 331
 332   for (argi = 0; argi < argc; argi++)
 333     (*argvp)[(*argcp)++] = xstrdup (argv[argi]);
 334   (*argvp)[(*argcp)] = NULL;
 335 }
 336
 337 /* String for 'set compile-gcc' and 'show compile-gcc'.  */
 338 static char *compile_gcc;
 339
 340 /* Implement 'show compile-gcc'.  */
 341
 342 static void
 343 show_compile_gcc (struct ui_file *file, int from_tty,
 344                   struct cmd_list_element *c, const char *value)
 345 {
 346   fprintf_filtered (file, _("Compile command GCC driver filename is \"%s\".\n"),
 347                     value);
 348 }
 349
 350 /* Return DW_AT_producer parsed for get_selected_frame () (if any).
 351    Return NULL otherwise.
 352
 353    GCC already filters its command-line arguments only for the suitable ones to
 354    put into DW_AT_producer - see GCC function gen_producer_string.  */
 355
 356 static const char *
 357 get_selected_pc_producer_options (void)
 358 {
 359   CORE_ADDR pc = get_frame_pc (get_selected_frame (NULL));
 360   struct compunit_symtab *symtab = find_pc_compunit_symtab (pc);
 361   const char *cs;
 362
 363   if (symtab == NULL || symtab->producer == NULL
 364       || !startswith (symtab->producer, "GNU "))
 365     return NULL;
 366
 367   cs = symtab->producer;
 368   while (*cs != 0 && *cs != '-')
 369     cs = skip_spaces (skip_to_space (cs));
 370   if (*cs != '-')
 371     return NULL;
 372   return cs;
 373 }
 374
 375 /* Filter out unwanted options from *ARGCP and ARGV.  */
 376
 377 static void
 378 filter_args (int *argcp, char **argv)
 379 {
 380   char **destv;
 381
 382   for (destv = argv; *argv != NULL; argv++)
 383     {
 384       /* -fpreprocessed may get in commonly from ccache.  */
 385       if (strcmp (*argv, "-fpreprocessed") == 0)
 386         {
 387           xfree (*argv);
 388           (*argcp)--;
 389           continue;
 390         }
 391       *destv++ = *argv;
 392     }
 393   *destv = NULL;
 394 }
 395
 396 /* Produce final vector of GCC compilation options.  First element is target
 397    size ("-m64", "-m32" etc.), optionally followed by DW_AT_producer options
 398    and then compile-args string GDB variable.  */
 399
 400 static void
 401 get_args (const struct compile_instance *compiler, struct gdbarch *gdbarch,
 402           int *argcp, char ***argvp)
 403 {
 404   const char *cs_producer_options;
 405   int argc_compiler;
 406   char **argv_compiler;
 407
 408   build_argc_argv (gdbarch_gcc_target_options (gdbarch),
 409                    argcp, argvp);
 410
 411   cs_producer_options = get_selected_pc_producer_options ();
 412   if (cs_producer_options != NULL)
 413     {
 414       int argc_producer;
 415       char **argv_producer;
 416
 417       build_argc_argv (cs_producer_options, &argc_producer, &argv_producer);
 418       filter_args (&argc_producer, argv_producer);
 419       append_args (argcp, argvp, argc_producer, argv_producer);
 420       freeargv (argv_producer);
 421     }
 422
 423   build_argc_argv (compiler->gcc_target_options,
 424                    &argc_compiler, &argv_compiler);
 425   append_args (argcp, argvp, argc_compiler, argv_compiler);
 426   freeargv (argv_compiler);
 427
 428   append_args (argcp, argvp, compile_args_argc, compile_args_argv);
 429 }
 430
 431 /* A cleanup function to destroy a gdb_gcc_instance.  */
 432
 433 static void
 434 cleanup_compile_instance (void *arg)
 435 {
 436   struct compile_instance *inst = (struct compile_instance *) arg;
 437
 438   inst->destroy (inst);
 439 }
 440
 441 /* A helper function suitable for use as the "print_callback" in the
 442    compiler object.  */
 443
 444 static void
 445 print_callback (void *ignore, const char *message)
 446 {
 447   fputs_filtered (message, gdb_stderr);
 448 }
 449
 450 /* Process the compilation request.  On success it returns the object
 451    and source file names.  On an error condition, error () is
 452    called.  */
 453
 454 static compile_file_names
 455 compile_to_object (struct command_line *cmd, const char *cmd_string,
 456                    enum compile_i_scope_types scope)
 457 {
 458   struct compile_instance *compiler;
 459   struct cleanup *cleanup;
 460   const struct block *expr_block;
 461   CORE_ADDR trash_pc, expr_pc;
 462   int argc;
 463   char **argv;
 464   int ok;
 465   FILE *src;
 466   struct gdbarch *gdbarch = get_current_arch ();
 467   char *triplet_rx;
 468   char *error_message;
 469
 470   if (!target_has_execution)
 471     error (_("The program must be running for the compile command to "\
 472              "work."));
 473
 474   expr_block = get_expr_block_and_pc (&trash_pc);
 475   expr_pc = get_frame_address_in_block (get_selected_frame (NULL));
 476
 477   /* Set up instance and context for the compiler.  */
 478   if (current_language->la_get_compile_instance == NULL)
 479     error (_("No compiler support for language %s."),
 480            current_language->la_name);
 481   compiler = current_language->la_get_compile_instance ();
 482   cleanup = make_cleanup (cleanup_compile_instance, compiler);
 483
 484   compiler->fe->ops->set_print_callback (compiler->fe, print_callback, NULL);
 485
 486   compiler->scope = scope;
 487   compiler->block = expr_block;
 488
 489   /* From the provided expression, build a scope to pass to the
 490      compiler.  */
 491
 492   string_file input_buf;
 493   const char *input;
 494
 495   if (cmd != NULL)
 496     {
 497       struct command_line *iter;
 498
 499       for (iter = cmd->body_list[0]; iter; iter = iter->next)
 500         {
 501           input_buf.puts (iter->line);
 502           input_buf.puts ("\n");
 503         }
 504
 505       input = input_buf.c_str ();
 506     }
 507   else if (cmd_string != NULL)
 508     input = cmd_string;
 509   else
 510     error (_("Neither a simple expression, or a multi-line specified."));
 511
 512   std::string code
 513     = current_language->la_compute_program (compiler, input, gdbarch,
 514                                             expr_block, expr_pc);
 515   if (compile_debug)
 516     fprintf_unfiltered (gdb_stdlog, "debug output:\n\n%s", code.c_str ());
 517
 518   if (compiler->fe->ops->version >= GCC_FE_VERSION_1)
 519     compiler->fe->ops->set_verbose (compiler->fe, compile_debug);
 520
 521   if (compile_gcc[0] != 0)
 522     {
 523       if (compiler->fe->ops->version < GCC_FE_VERSION_1)
 524         error (_("Command 'set compile-gcc' requires GCC version 6 or higher "
 525                  "(libcc1 interface version 1 or higher)"));
 526
 527       compiler->fe->ops->set_driver_filename (compiler->fe, compile_gcc);
 528     }
 529   else
 530     {
 531       const char *os_rx = osabi_triplet_regexp (gdbarch_osabi (gdbarch));
 532       const char *arch_rx = gdbarch_gnu_triplet_regexp (gdbarch);
 533
 534       /* Allow triplets with or without vendor set.  */
 535       triplet_rx = concat (arch_rx, "(-[^-]*)?-", os_rx, (char *) NULL);
 536       make_cleanup (xfree, triplet_rx);
 537
 538       if (compiler->fe->ops->version >= GCC_FE_VERSION_1)
 539         compiler->fe->ops->set_triplet_regexp (compiler->fe, triplet_rx);
 540     }
 541
 542   /* Set compiler command-line arguments.  */
 543   get_args (compiler, gdbarch, &argc, &argv);
 544   gdb_argv argv_holder (argv);
 545
 546   if (compiler->fe->ops->version >= GCC_FE_VERSION_1)
 547     error_message = compiler->fe->ops->set_arguments (compiler->fe, argc, argv);
 548   else
 549     error_message = compiler->fe->ops->set_arguments_v0 (compiler->fe, triplet_rx,
 550                                                          argc, argv);
 551   if (error_message != NULL)
 552     {
 553       make_cleanup (xfree, error_message);
 554       error ("%s", error_message);
 555     }
 556
 557   if (compile_debug)
 558     {
 559       int argi;
 560
 561       fprintf_unfiltered (gdb_stdlog, "Passing %d compiler options:\n", argc);
 562       for (argi = 0; argi < argc; argi++)
 563         fprintf_unfiltered (gdb_stdlog, "Compiler option %d: <%s>\n",
 564                             argi, argv[argi]);
 565     }
 566
 567   compile_file_names fnames = get_new_file_names ();
 568
 569   gdb::optional<gdb::unlinker> source_remover;
 570
 571   {
 572     gdb_file_up src = gdb_fopen_cloexec (fnames.source_file (), "w");
 573     if (src == NULL)
 574       perror_with_name (_("Could not open source file for writing"));
 575
 576     source_remover.emplace (fnames.source_file ());
 577
 578     if (fputs (code.c_str (), src.get ()) == EOF)
 579       perror_with_name (_("Could not write to source file"));
 580   }
 581
 582   if (compile_debug)
 583     fprintf_unfiltered (gdb_stdlog, "source file produced: %s\n\n",
 584                         fnames.source_file ());
 585
 586   /* Call the compiler and start the compilation process.  */
 587   compiler->fe->ops->set_source_file (compiler->fe, fnames.source_file ());
 588
 589   if (compiler->fe->ops->version >= GCC_FE_VERSION_1)
 590     ok = compiler->fe->ops->compile (compiler->fe, fnames.object_file ());
 591   else
 592     ok = compiler->fe->ops->compile_v0 (compiler->fe, fnames.object_file (),
 593                                         compile_debug);
 594   if (!ok)
 595     error (_("Compilation failed."));
 596
 597   if (compile_debug)
 598     fprintf_unfiltered (gdb_stdlog, "object file produced: %s\n\n",
 599                         fnames.object_file ());
 600
 601   /* Keep the source file.  */
 602   source_remover->keep ();
 603
 604   do_cleanups (cleanup);
 605
 606   return fnames;
 607 }
 608
 609 /* The "compile" prefix command.  */
 610
 611 static void
 612 compile_command (const char *args, int from_tty)
 613 {
 614   /* If a sub-command is not specified to the compile prefix command,
 615      assume it is a direct code compilation.  */
 616   compile_code_command (args, from_tty);
 617 }
 618
 619 /* See compile.h.  */
 620
 621 void
 622 eval_compile_command (struct command_line *cmd, const char *cmd_string,
 623                       enum compile_i_scope_types scope, void *scope_data)
 624 {
 625   struct compile_module *compile_module;
 626
 627   compile_file_names fnames = compile_to_object (cmd, cmd_string, scope);
 628
 629   gdb::unlinker object_remover (fnames.object_file ());
 630   gdb::unlinker source_remover (fnames.source_file ());
 631
 632   compile_module = compile_object_load (fnames, scope, scope_data);
 633   if (compile_module == NULL)
 634     {
 635       gdb_assert (scope == COMPILE_I_PRINT_ADDRESS_SCOPE);
 636       eval_compile_command (cmd, cmd_string,
 637                             COMPILE_I_PRINT_VALUE_SCOPE, scope_data);
 638       return;
 639     }
 640
 641   /* Keep the files.  */
 642   source_remover.keep ();
 643   object_remover.keep ();
 644
 645   compile_object_run (compile_module);
 646 }
 647
 648 /* See compile/compile-internal.h.  */
 649
 650 std::string
 651 compile_register_name_mangled (struct gdbarch *gdbarch, int regnum)
 652 {
 653   const char *regname = gdbarch_register_name (gdbarch, regnum);
 654
 655   return string_printf ("__%s", regname);
 656 }
 657
 658 /* See compile/compile-internal.h.  */
 659
 660 int
 661 compile_register_name_demangle (struct gdbarch *gdbarch,
 662                                  const char *regname)
 663 {
 664   int regnum;
 665
 666   if (regname[0] != '_' || regname[1] != '_')
 667     error (_("Invalid register name \"%s\"."), regname);
 668   regname += 2;
 669
 670   for (regnum = 0; regnum < gdbarch_num_regs (gdbarch); regnum++)
 671     if (strcmp (regname, gdbarch_register_name (gdbarch, regnum)) == 0)
 672       return regnum;
 673
 674   error (_("Cannot find gdbarch register \"%s\"."), regname);
 675 }
 676
 677 void
 678 _initialize_compile (void)
 679 {
 680   struct cmd_list_element *c = NULL;
 681
 682   add_prefix_cmd ("compile", class_obscure, compile_command,
 683                   _("\
 684 Command to compile source code and inject it into the inferior."),
 685                   &compile_command_list, "compile ", 1, &cmdlist);
 686   add_com_alias ("expression", "compile", class_obscure, 0);
 687
 688   add_cmd ("code", class_obscure, compile_code_command,
 689            _("\
 690 Compile, inject, and execute code.\n\
 691 \n\
 692 Usage: compile code [-r|-raw] [--] [CODE]\n\
 693 -r|-raw: Suppress automatic 'void _gdb_expr () { CODE }' wrapping.\n\
 694 --: Do not parse any options beyond this delimiter.  All text to the\n\
 695     right will be treated as source code.\n\
 696 \n\
 697 The source code may be specified as a simple one line expression, e.g.:\n\
 698 \n\
 699     compile code printf(\"Hello world\\n\");\n\
 700 \n\
 701 Alternatively, you can type a multiline expression by invoking\n\
 702 this command with no argument.  GDB will then prompt for the\n\
 703 expression interactively; type a line containing \"end\" to\n\
 704 indicate the end of the expression."),
 705            &compile_command_list);
 706
 707   c = add_cmd ("file", class_obscure, compile_file_command,
 708                _("\
 709 Evaluate a file containing source code.\n\
 710 \n\
 711 Usage: compile file [-r|-raw] [filename]\n\
 712 -r|-raw: Suppress automatic 'void _gdb_expr () { CODE }' wrapping."),
 713                &compile_command_list);
 714   set_cmd_completer (c, filename_completer);
 715
 716   add_cmd ("print", class_obscure, compile_print_command,
 717            _("\
 718 Evaluate EXPR by using the compiler and print result.\n\
 719 \n\
 720 Usage: compile print[/FMT] [EXPR]\n\
 721 \n\
 722 The expression may be specified on the same line as the command, e.g.:\n\
 723 \n\
 724     compile print i\n\
 725 \n\
 726 Alternatively, you can type a multiline expression by invoking\n\
 727 this command with no argument.  GDB will then prompt for the\n\
 728 expression interactively; type a line containing \"end\" to\n\
 729 indicate the end of the expression.\n\
 730 \n\
 731 EXPR may be preceded with /FMT, where FMT is a format letter\n\
 732 but no count or size letter (see \"x\" command)."),
 733            &compile_command_list);
 734
 735   add_setshow_boolean_cmd ("compile", class_maintenance, &compile_debug, _("\
 736 Set compile command debugging."), _("\
 737 Show compile command debugging."), _("\
 738 When on, compile command debugging is enabled."),
 739                            NULL, show_compile_debug,
 740                            &setdebuglist, &showdebuglist);
 741
 742   add_setshow_string_cmd ("compile-args", class_support,
 743                           &compile_args,
 744                           _("Set compile command GCC command-line arguments"),
 745                           _("Show compile command GCC command-line arguments"),
 746                           _("\
 747 Use options like -I (include file directory) or ABI settings.\n\
 748 String quoting is parsed like in shell, for example:\n\
 749   -mno-align-double \"-I/dir with a space/include\""),
 750                           set_compile_args, show_compile_args, &setlist, &showlist);
 751
 752   /* Override flags possibly coming from DW_AT_producer.  */
 753   compile_args = xstrdup ("-O0 -gdwarf-4"
 754   /* We use -fPIE Otherwise GDB would need to reserve space large enough for
 755      any object file in the inferior in advance to get the final address when
 756      to link the object file to and additionally the default system linker
 757      script would need to be modified so that one can specify there the
 758      absolute target address.
 759      -fPIC is not used at is would require from GDB to generate .got.  */
 760                          " -fPIE"
 761   /* We want warnings, except for some commonly happening for GDB commands.  */
 762                          " -Wall "
 763                          " -Wno-implicit-function-declaration"
 764                          " -Wno-unused-but-set-variable"
 765                          " -Wno-unused-variable"
 766   /* Override CU's possible -fstack-protector-strong.  */
 767                          " -fno-stack-protector"
 768   );
 769   set_compile_args (compile_args, 0, NULL);
 770
 771   add_setshow_optional_filename_cmd ("compile-gcc", class_support,
 772                                      &compile_gcc,
 773                                      _("Set compile command "
 774                                        "GCC driver filename"),
 775                                      _("Show compile command "
 776                                        "GCC driver filename"),
 777                                      _("\
 778 It should be absolute filename of the gcc executable.\n\
 779 If empty the default target triplet will be searched in $PATH."),
 780                                      NULL, show_compile_gcc, &setlist,
 781                                      &showlist);
 782   compile_gcc = xstrdup ("");
 783 }