gas/as.c

   1 /* as.c - GAS main program.
   2    Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 1996
   3    Free Software Foundation, Inc.
   4
   5    This file is part of GAS, the GNU Assembler.
   6
   7    GAS 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 2, or (at your option)
  10    any later version.
  11
  12    GAS 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 GAS; see the file COPYING.  If not, write to the Free
  19    Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20    02111-1307, USA. */
  21
  22 /*
  23  * Main program for AS; a 32-bit assembler of GNU.
  24  * Understands command arguments.
  25  * Has a few routines that don't fit in other modules because they
  26  * are shared.
  27  *
  28  *
  29  *                      bugs
  30  *
  31  * : initialisers
  32  *      Since no-one else says they will support them in future: I
  33  * don't support them now.
  34  *
  35  */
  36
  37 #include "ansidecl.h"
  38 #include "libiberty.h"
  39
  40 #define COMMON
  41
  42 #include "as.h"
  43 #include "subsegs.h"
  44 #include "output-file.h"
  45 #include "sb.h"
  46 #include "macro.h"
  47
  48 #ifdef HAVE_SBRK
  49 #ifdef NEED_DECLARATION_SBRK
  50 extern PTR sbrk ();
  51 #endif
  52 #endif
  53
  54 static void perform_an_assembly_pass PARAMS ((int argc, char **argv));
  55 static int macro_expr PARAMS ((const char *, int, sb *, int *));
  56
  57 int listing;                    /* true if a listing is wanted */
  58
  59 static char *listing_filename = NULL;   /* Name of listing file.  */
  60
  61 /* Maximum level of macro nesting.  */
  62
  63 int max_macro_nest = 100;
  64
  65 char *myname;                   /* argv[0] */
  66 #ifdef BFD_ASSEMBLER
  67 segT reg_section, expr_section;
  68 segT text_section, data_section, bss_section;
  69 #endif
  70
  71 int chunksize = 5000;
  72
  73 /* To monitor memory allocation more effectively, make this non-zero.
  74    Then the chunk sizes for gas and bfd will be reduced.  */
  75 int debug_memory = 0;
  76
  77 /* We build a list of defsyms as we read the options, and then define
  78    them after we have initialized everything.  */
  79
  80 struct defsym_list
  81 {
  82   struct defsym_list *next;
  83   char *name;
  84   valueT value;
  85 };
  86
  87 static struct defsym_list *defsyms;
  88 \f
  89 void
  90 print_version_id ()
  91 {
  92   static int printed;
  93   if (printed)
  94     return;
  95   printed = 1;
  96
  97   fprintf (stderr, "GNU assembler version %s (%s)", GAS_VERSION, TARGET_ALIAS);
  98 #ifdef BFD_ASSEMBLER
  99   fprintf (stderr, ", using BFD version %s", BFD_VERSION);
 100 #endif
 101   fprintf (stderr, "\n");
 102 }
 103
 104 void
 105 show_usage (stream)
 106      FILE *stream;
 107 {
 108   fprintf (stream, "Usage: %s [option...] [asmfile...]\n", myname);
 109
 110   fprintf (stream, "\
 111 Options:\n\
 112 -a[sub-option...]       turn on listings\n\
 113   Sub-options [default hls]:\n\
 114   d     omit debugging directives\n\
 115   h     include high-level source\n\
 116   l     include assembly\n\
 117   n     omit forms processing\n\
 118   s     include symbols\n\
 119   =file set listing file name (must be last sub-option)\n");
 120   fprintf (stream, "\
 121 -D                      produce assembler debugging messages\n\
 122 --defsym SYM=VAL        define symbol SYM to given value\n\
 123 -f                      skip whitespace and comment preprocessing\n\
 124 --help                  show this message and exit\n\
 125 -I DIR                  add DIR to search list for .include directives\n\
 126 -J                      don't warn about signed overflow\n\
 127 -K                      warn when differences altered for long displacements\n\
 128 -L                      keep local symbols (starting with `L')\n");
 129   fprintf (stream, "\
 130 -M,--mri                assemble in MRI compatibility mode\n\
 131 -nocpp                  ignored\n\
 132 -o OBJFILE              name the object-file output OBJFILE (default a.out)\n\
 133 -R                      fold data section into text section\n\
 134 --statistics            print various measured statistics from execution\n\
 135 --version               print assembler version number and exit\n\
 136 -W                      suppress warnings\n\
 137 -w                      ignored\n\
 138 -X                      ignored\n\
 139 -Z                      generate object file even after errors\n");
 140
 141   md_show_usage (stream);
 142
 143   fprintf (stream, "\nReport bugs to bug-gnu-utils@prep.ai.mit.edu\n");
 144 }
 145
 146 #ifdef USE_EMULATIONS
 147 #define EMULATION_ENVIRON "AS_EMULATION"
 148
 149 extern struct emulation mipsbelf, mipslelf, mipself;
 150 extern struct emulation mipsbecoff, mipslecoff, mipsecoff;
 151
 152 static struct emulation *const emulations[] = { EMULATIONS };
 153 static const int n_emulations = sizeof (emulations) / sizeof (emulations[0]);
 154
 155 static void
 156 select_emulation_mode (argc, argv)
 157      int argc;
 158      char **argv;
 159 {
 160   int i;
 161   char *p, *em = 0;
 162
 163   for (i = 1; i < argc; i++)
 164     if (!strncmp ("--em", argv[i], 4))
 165       break;
 166
 167   if (i == argc)
 168     goto do_default;
 169
 170   p = strchr (argv[i], '=');
 171   if (p)
 172     p++;
 173   else
 174     p = argv[i+1];
 175
 176   if (!p || !*p)
 177     as_fatal ("missing emulation mode name");
 178   em = p;
 179
 180  do_default:
 181   if (em == 0)
 182     em = getenv (EMULATION_ENVIRON);
 183   if (em == 0)
 184     em = DEFAULT_EMULATION;
 185
 186   if (em)
 187     {
 188       for (i = 0; i < n_emulations; i++)
 189         if (!strcmp (emulations[i]->name, em))
 190           break;
 191       if (i == n_emulations)
 192         as_fatal ("unrecognized emulation name `%s'", em);
 193       this_emulation = emulations[i];
 194     }
 195   else
 196     this_emulation = emulations[0];
 197
 198   this_emulation->init ();
 199 }
 200
 201 const char *
 202 default_emul_bfd_name ()
 203 {
 204   abort ();
 205   return NULL;
 206 }
 207
 208 void
 209 common_emul_init ()
 210 {
 211   this_format = this_emulation->format;
 212
 213   if (this_emulation->leading_underscore == 2)
 214     this_emulation->leading_underscore = this_format->dfl_leading_underscore;
 215
 216   if (this_emulation->default_endian != 2)
 217     target_big_endian = this_emulation->default_endian;
 218
 219   if (this_emulation->fake_label_name == 0)
 220     {
 221       if (this_emulation->leading_underscore)
 222         this_emulation->fake_label_name = "L0\001";
 223       else
 224         /* What other parameters should we test?  */
 225         this_emulation->fake_label_name = ".L0\001";
 226     }
 227 }
 228 #endif
 229
 230 /*
 231  * Since it is easy to do here we interpret the special arg "-"
 232  * to mean "use stdin" and we set that argv[] pointing to "".
 233  * After we have munged argv[], the only things left are source file
 234  * name(s) and ""(s) denoting stdin. These file names are used
 235  * (perhaps more than once) later.
 236  *
 237  * check for new machine-dep cmdline options in
 238  * md_parse_option definitions in config/tc-*.c
 239  */
 240
 241 void
 242 parse_args (pargc, pargv)
 243      int *pargc;
 244      char ***pargv;
 245 {
 246   int old_argc, new_argc;
 247   char **old_argv, **new_argv;
 248
 249   /* Starting the short option string with '-' is for programs that
 250      expect options and other ARGV-elements in any order and that care about
 251      the ordering of the two.  We describe each non-option ARGV-element
 252      as if it were the argument of an option with character code 1.  */
 253
 254   char *shortopts;
 255   extern CONST char *md_shortopts;
 256   static const char std_shortopts[] =
 257     {
 258       '-', 'J',
 259 #ifndef WORKING_DOT_WORD
 260       /* -K is not meaningful if .word is not being hacked.  */
 261       'K',
 262 #endif
 263       'L', 'M', 'R', 'W', 'Z', 'f', 'a', ':', ':', 'D', 'I', ':', 'o', ':',
 264 #ifndef VMS
 265       /* -v takes an argument on VMS, so we don't make it a generic
 266          option.  */
 267       'v',
 268 #endif
 269       'w', 'X',
 270       '\0'
 271     };
 272   struct option *longopts;
 273   extern struct option md_longopts[];
 274   extern size_t md_longopts_size;
 275   static const struct option std_longopts[] = {
 276 #define OPTION_HELP (OPTION_STD_BASE)
 277     {"help", no_argument, NULL, OPTION_HELP},
 278     {"mri", no_argument, NULL, 'M'},
 279 #define OPTION_NOCPP (OPTION_STD_BASE + 1)
 280     {"nocpp", no_argument, NULL, OPTION_NOCPP},
 281 #define OPTION_STATISTICS (OPTION_STD_BASE + 2)
 282     {"statistics", no_argument, NULL, OPTION_STATISTICS},
 283 #define OPTION_VERSION (OPTION_STD_BASE + 3)
 284     {"version", no_argument, NULL, OPTION_VERSION},
 285 #define OPTION_DUMPCONFIG (OPTION_STD_BASE + 4)
 286     {"dump-config", no_argument, NULL, OPTION_DUMPCONFIG},
 287 #define OPTION_VERBOSE (OPTION_STD_BASE + 5)
 288     {"verbose", no_argument, NULL, OPTION_VERBOSE},
 289 #define OPTION_EMULATION (OPTION_STD_BASE + 6)
 290     {"emulation", required_argument, NULL, OPTION_EMULATION},
 291 #define OPTION_DEFSYM (OPTION_STD_BASE + 7)
 292     {"defsym", required_argument, NULL, OPTION_DEFSYM}
 293   };
 294
 295   /* Construct the option lists from the standard list and the
 296      target dependent list.  */
 297   shortopts = concat (std_shortopts, md_shortopts, (char *) NULL);
 298   longopts = (struct option *) xmalloc (sizeof (std_longopts) + md_longopts_size);
 299   memcpy (longopts, std_longopts, sizeof (std_longopts));
 300   memcpy ((char *) longopts + sizeof (std_longopts),
 301           md_longopts, md_longopts_size);
 302
 303   /* Make a local copy of the old argv.  */
 304   old_argc = *pargc;
 305   old_argv = *pargv;
 306
 307   /* Initialize a new argv that contains no options.  */
 308   new_argv = (char **) xmalloc (sizeof (char *) * (old_argc + 1));
 309   new_argv[0] = old_argv[0];
 310   new_argc = 1;
 311   new_argv[new_argc] = NULL;
 312
 313   while (1)
 314     {
 315       /* getopt_long_only is like getopt_long, but '-' as well as '--' can
 316          indicate a long option.  */
 317       int longind;
 318       int optc = getopt_long_only (old_argc, old_argv, shortopts, longopts,
 319                                    &longind);
 320
 321       if (optc == -1)
 322         break;
 323
 324       switch (optc)
 325         {
 326         default:
 327           /* md_parse_option should return 1 if it recognizes optc,
 328              0 if not.  */
 329           if (md_parse_option (optc, optarg) != 0)
 330             break;
 331           /* `-v' isn't included in the general short_opts list, so check for
 332              it explicity here before deciding we've gotten a bad argument.  */
 333           if (optc == 'v')
 334             {
 335 #ifdef VMS
 336               /* Telling getopt to treat -v's value as optional can result
 337                  in it picking up a following filename argument here.  The
 338                  VMS code in md_parse_option can return 0 in that case,
 339                  but it has no way of pushing the filename argument back.  */
 340               if (optarg && *optarg)
 341                 new_argv[new_argc++] = optarg,  new_argv[new_argc] = NULL;
 342               else
 343 #else
 344               case 'v':
 345 #endif
 346               case OPTION_VERBOSE:
 347                 print_version_id ();
 348               break;
 349             }
 350           /*FALLTHRU*/
 351
 352         case '?':
 353           exit (EXIT_FAILURE);
 354
 355         case 1:                 /* File name.  */
 356           if (!strcmp (optarg, "-"))
 357             optarg = "";
 358           new_argv[new_argc++] = optarg;
 359           new_argv[new_argc] = NULL;
 360           break;
 361
 362         case OPTION_HELP:
 363           show_usage (stdout);
 364           exit (EXIT_SUCCESS);
 365
 366         case OPTION_NOCPP:
 367           break;
 368
 369         case OPTION_STATISTICS:
 370           flag_print_statistics = 1;
 371           break;
 372
 373         case OPTION_VERSION:
 374           /* This output is intended to follow the GNU standards document.  */
 375           printf ("GNU assembler %s\n", GAS_VERSION);
 376           printf ("Copyright 1996 Free Software Foundation, Inc.\n");
 377           printf ("\
 378 This program is free software; you may redistribute it under the terms of\n\
 379 the GNU General Public License.  This program has absolutely no warranty.\n");
 380           printf ("This assembler was configured for a target of `%s'.\n",
 381                   TARGET_ALIAS);
 382           exit (EXIT_SUCCESS);
 383
 384         case OPTION_EMULATION:
 385 #ifdef USE_EMULATIONS
 386           if (strcmp (optarg, this_emulation->name))
 387             as_fatal ("multiple emulation names specified");
 388 #else
 389           as_fatal ("emulations not handled in this configuration");
 390 #endif
 391           break;
 392
 393         case OPTION_DUMPCONFIG:
 394           fprintf (stderr, "alias = %s\n", TARGET_ALIAS);
 395           fprintf (stderr, "canonical = %s\n", TARGET_CANONICAL);
 396           fprintf (stderr, "cpu-type = %s\n", TARGET_CPU);
 397 #ifdef TARGET_OBJ_FORMAT
 398           fprintf (stderr, "format = %s\n", TARGET_OBJ_FORMAT);
 399 #endif
 400 #ifdef TARGET_FORMAT
 401           fprintf (stderr, "bfd-target = %s\n", TARGET_FORMAT);
 402 #endif
 403           exit (EXIT_SUCCESS);
 404
 405         case OPTION_DEFSYM:
 406           {
 407             char *s;
 408             long i;
 409             struct defsym_list *n;
 410
 411             for (s = optarg; *s != '\0' && *s != '='; s++)
 412               ;
 413             if (*s == '\0')
 414               as_fatal ("bad defsym; format is --defsym name=value");
 415             *s++ = '\0';
 416             i = strtol (s, (char **) NULL, 0);
 417             n = (struct defsym_list *) xmalloc (sizeof *n);
 418             n->next = defsyms;
 419             n->name = optarg;
 420             n->value = i;
 421             defsyms = n;
 422           }
 423           break;
 424
 425         case 'J':
 426           flag_signed_overflow_ok = 1;
 427           break;
 428
 429 #ifndef WORKING_DOT_WORD
 430         case 'K':
 431           flag_warn_displacement = 1;
 432           break;
 433 #endif
 434
 435         case 'L':
 436           flag_keep_locals = 1;
 437           break;
 438
 439         case 'M':
 440           flag_mri = 1;
 441 #ifdef TC_M68K
 442           flag_m68k_mri = 1;
 443 #endif
 444           break;
 445
 446         case 'R':
 447           flag_readonly_data_in_text = 1;
 448           break;
 449
 450         case 'W':
 451           flag_no_warnings = 1;
 452           break;
 453
 454         case 'Z':
 455           flag_always_generate_output = 1;
 456           break;
 457
 458         case 'a':
 459           if (optarg)
 460             {
 461               while (*optarg)
 462                 {
 463                   switch (*optarg)
 464                     {
 465                     case 'd':
 466                       listing |= LISTING_NODEBUG;
 467                       break;
 468                     case 'h':
 469                       listing |= LISTING_HLL;
 470                       break;
 471                     case 'l':
 472                       listing |= LISTING_LISTING;
 473                       break;
 474                     case 'n':
 475                       listing |= LISTING_NOFORM;
 476                       break;
 477                     case 's':
 478                       listing |= LISTING_SYMBOLS;
 479                       break;
 480                     case '=':
 481                       listing_filename = xstrdup (optarg + 1);
 482                       optarg += strlen (listing_filename);
 483                       break;
 484                     default:
 485                       as_fatal ("invalid listing option `%c'", *optarg);
 486                       break;
 487                     }
 488                   optarg++;
 489                 }
 490             }
 491           if (!listing)
 492             listing = LISTING_DEFAULT;
 493           break;
 494
 495         case 'D':
 496           /* DEBUG is implemented: it debugs different */
 497           /* things from other people's assemblers. */
 498           flag_debug = 1;
 499           break;
 500
 501         case 'f':
 502           flag_no_comments = 1;
 503           break;
 504
 505         case 'I':
 506           {                     /* Include file directory */
 507             char *temp = xstrdup (optarg);
 508             add_include_dir (temp);
 509             break;
 510           }
 511
 512         case 'o':
 513           out_file_name = xstrdup (optarg);
 514           break;
 515
 516         case 'w':
 517           break;
 518
 519         case 'X':
 520           /* -X means treat warnings as errors */
 521           break;
 522         }
 523     }
 524
 525   free (shortopts);
 526   free (longopts);
 527
 528   *pargc = new_argc;
 529   *pargv = new_argv;
 530 }
 531
 532 static void dump_statistics ();
 533 static long start_time;
 534
 535 int
 536 main (argc, argv)
 537      int argc;
 538      char **argv;
 539 {
 540   int macro_alternate;
 541   int macro_strip_at;
 542   int keep_it;
 543
 544   start_time = get_run_time ();
 545
 546   if (debug_memory)
 547     {
 548 #ifdef BFD_ASSEMBLER
 549       extern long _bfd_chunksize;
 550       _bfd_chunksize = 64;
 551 #endif
 552       chunksize = 64;
 553     }
 554
 555 #ifdef HOST_SPECIAL_INIT
 556   HOST_SPECIAL_INIT (argc, argv);
 557 #endif
 558
 559   myname = argv[0];
 560   xmalloc_set_program_name (myname);
 561
 562   START_PROGRESS (myname, 0);
 563
 564 #ifndef OBJ_DEFAULT_OUTPUT_FILE_NAME
 565 #define OBJ_DEFAULT_OUTPUT_FILE_NAME "a.out"
 566 #endif
 567
 568   out_file_name = OBJ_DEFAULT_OUTPUT_FILE_NAME;
 569
 570   hex_init ();
 571 #ifdef BFD_ASSEMBLER
 572   bfd_init ();
 573   bfd_set_error_program_name (myname);
 574 #endif
 575
 576 #ifdef USE_EMULATIONS
 577   select_emulation_mode (argc, argv);
 578 #endif
 579
 580   PROGRESS (1);
 581   symbol_begin ();
 582   frag_init ();
 583   subsegs_begin ();
 584   parse_args (&argc, &argv);
 585   read_begin ();
 586   input_scrub_begin ();
 587   expr_begin ();
 588
 589   if (flag_print_statistics)
 590     xatexit (dump_statistics);
 591
 592   macro_alternate = 0;
 593   macro_strip_at = 0;
 594 #ifdef TC_I960
 595   macro_strip_at = flag_mri;
 596 #endif
 597 #ifdef TC_A29K
 598   /* For compatibility with the AMD 29K family macro assembler
 599      specification.  */
 600   macro_alternate = 1;
 601   macro_strip_at = 1;
 602 #endif
 603
 604   macro_init (macro_alternate, flag_mri, macro_strip_at, macro_expr);
 605
 606   PROGRESS (1);
 607
 608 #ifdef BFD_ASSEMBLER
 609   output_file_create (out_file_name);
 610   assert (stdoutput != 0);
 611 #endif
 612
 613 #ifdef tc_init_after_args
 614   tc_init_after_args ();
 615 #endif
 616
 617   /* Now that we have fully initialized, and have created the output
 618      file, define any symbols requested by --defsym command line
 619      arguments.  */
 620   while (defsyms != NULL)
 621     {
 622       symbolS *sym;
 623       struct defsym_list *next;
 624
 625       sym = symbol_new (defsyms->name, absolute_section, defsyms->value,
 626                         &zero_address_frag);
 627       symbol_table_insert (sym);
 628       next = defsyms->next;
 629       free (defsyms);
 630       defsyms = next;
 631     }
 632
 633   PROGRESS (1);
 634
 635   perform_an_assembly_pass (argc, argv);        /* Assemble it. */
 636
 637 #ifdef md_end
 638   md_end ();
 639 #endif
 640
 641   if (seen_at_least_1_file ()
 642       && !((had_warnings () && flag_always_generate_output)
 643            || had_errors () > 0))
 644     keep_it = 1;
 645   else
 646     keep_it = 0;
 647
 648   if (keep_it)
 649     write_object_file ();
 650
 651 #ifndef NO_LISTING
 652   listing_print (listing_filename);
 653 #endif
 654
 655 #ifndef OBJ_VMS /* does its own file handling */
 656 #ifndef BFD_ASSEMBLER
 657   if (keep_it)
 658 #endif
 659     output_file_close (out_file_name);
 660 #endif
 661
 662   if (!keep_it)
 663     unlink (out_file_name);
 664
 665   input_scrub_end ();
 666
 667   END_PROGRESS (myname);
 668
 669   /* Use xexit instead of return, because under VMS environments they
 670      may not place the same interpretation on the value given.  */
 671   if ((had_warnings () && flag_always_generate_output)
 672       || had_errors () > 0)
 673     xexit (EXIT_FAILURE);
 674   xexit (EXIT_SUCCESS);
 675 }
 676
 677 static void
 678 dump_statistics ()
 679 {
 680   extern char **environ;
 681 #ifdef HAVE_SBRK
 682   char *lim = (char *) sbrk (0);
 683 #endif
 684   long run_time = get_run_time () - start_time;
 685
 686   fprintf (stderr, "%s: total time in assembly: %ld.%06ld\n",
 687            myname, run_time / 1000000, run_time % 1000000);
 688 #ifdef HAVE_SBRK
 689   fprintf (stderr, "%s: data size %ld\n",
 690            myname, (long) (lim - (char *) &environ));
 691 #endif
 692
 693   subsegs_print_statistics (stderr);
 694   write_print_statistics (stderr);
 695   symbol_print_statistics (stderr);
 696   read_print_statistics (stderr);
 697
 698 #ifdef tc_print_statistics
 699   tc_print_statistics (stderr);
 700 #endif
 701 #ifdef obj_print_statistics
 702   obj_print_statistics (stderr);
 703 #endif
 704 }
 705 \f
 706
 707 /*                      perform_an_assembly_pass()
 708  *
 709  * Here to attempt 1 pass over each input file.
 710  * We scan argv[*] looking for filenames or exactly "" which is
 711  * shorthand for stdin. Any argv that is NULL is not a file-name.
 712  * We set need_pass_2 TRUE if, after this, we still have unresolved
 713  * expressions of the form (unknown value)+-(unknown value).
 714  *
 715  * Note the un*x semantics: there is only 1 logical input file, but it
 716  * may be a catenation of many 'physical' input files.
 717  */
 718 static void
 719 perform_an_assembly_pass (argc, argv)
 720      int argc;
 721      char **argv;
 722 {
 723   int saw_a_file = 0;
 724 #ifdef BFD_ASSEMBLER
 725   flagword applicable;
 726 #endif
 727
 728   need_pass_2 = 0;
 729
 730 #ifndef BFD_ASSEMBLER
 731 #ifdef MANY_SEGMENTS
 732   {
 733     unsigned int i;
 734     for (i = SEG_E0; i < SEG_UNKNOWN; i++)
 735       segment_info[i].fix_root = 0;
 736   }
 737   /* Create the three fixed ones */
 738   {
 739     segT seg;
 740
 741 #ifdef TE_APOLLO
 742     seg = subseg_new (".wtext", 0);
 743 #else
 744     seg = subseg_new (".text", 0);
 745 #endif
 746     assert (seg == SEG_E0);
 747     seg = subseg_new (".data", 0);
 748     assert (seg == SEG_E1);
 749     seg = subseg_new (".bss", 0);
 750     assert (seg == SEG_E2);
 751 #ifdef TE_APOLLO
 752     create_target_segments ();
 753 #endif
 754   }
 755
 756 #else /* not MANY_SEGMENTS */
 757   text_fix_root = NULL;
 758   data_fix_root = NULL;
 759   bss_fix_root = NULL;
 760 #endif /* not MANY_SEGMENTS */
 761 #else /* BFD_ASSEMBLER */
 762   /* Create the standard sections, and those the assembler uses
 763      internally.  */
 764   text_section = subseg_new (".text", 0);
 765   data_section = subseg_new (".data", 0);
 766   bss_section = subseg_new (".bss", 0);
 767   /* @@ FIXME -- we're setting the RELOC flag so that sections are assumed
 768      to have relocs, otherwise we don't find out in time. */
 769   applicable = bfd_applicable_section_flags (stdoutput);
 770   bfd_set_section_flags (stdoutput, text_section,
 771                          applicable & (SEC_ALLOC | SEC_LOAD | SEC_RELOC
 772                                        | SEC_CODE | SEC_READONLY));
 773   /* @@ FIXME -- SEC_CODE seems to mean code only, rather than code possibly.*/
 774   bfd_set_section_flags (stdoutput, data_section,
 775                          applicable & (SEC_ALLOC | SEC_LOAD | SEC_RELOC));
 776   bfd_set_section_flags (stdoutput, bss_section, applicable & SEC_ALLOC);
 777   seg_info (bss_section)->bss = 1;
 778   subseg_new (BFD_ABS_SECTION_NAME, 0);
 779   subseg_new (BFD_UND_SECTION_NAME, 0);
 780   reg_section = subseg_new ("*GAS `reg' section*", 0);
 781   expr_section = subseg_new ("*GAS `expr' section*", 0);
 782
 783 #endif /* BFD_ASSEMBLER */
 784
 785   subseg_set (text_section, 0);
 786
 787   /* This may add symbol table entries, which requires having an open BFD,
 788      and sections already created, in BFD_ASSEMBLER mode.  */
 789   md_begin ();
 790
 791 #ifdef obj_begin
 792   obj_begin ();
 793 #endif
 794
 795   argv++;                       /* skip argv[0] */
 796   argc--;                       /* skip argv[0] */
 797   while (argc--)
 798     {
 799       if (*argv)
 800         {                       /* Is it a file-name argument? */
 801           PROGRESS (1);
 802           saw_a_file++;
 803           /* argv->"" if stdin desired, else->filename */
 804           read_a_source_file (*argv);
 805         }
 806       argv++;                   /* completed that argv */
 807     }
 808   if (!saw_a_file)
 809     read_a_source_file ("");
 810 }                               /* perform_an_assembly_pass() */
 811
 812 /* The interface between the macro code and gas expression handling.  */
 813
 814 static int
 815 macro_expr (emsg, idx, in, val)
 816      const char *emsg;
 817      int idx;
 818      sb *in;
 819      int *val;
 820 {
 821   char *hold;
 822   expressionS ex;
 823
 824   sb_terminate (in);
 825
 826   hold = input_line_pointer;
 827   input_line_pointer = in->ptr + idx;
 828   expression (&ex);
 829   idx = input_line_pointer - in->ptr;
 830   input_line_pointer = hold;
 831
 832   if (ex.X_op != O_constant)
 833     as_bad ("%s", emsg);
 834
 835   *val = (int) ex.X_add_number;
 836
 837   return idx;
 838 }
 839
 840 /* end of as.c */