gcc/tlink.c

   1 /* Scan linker error messages for missing template instantiations and provide
   2    them.
   3
   4    Copyright (C) 1995, 1998, 1999 Free Software Foundation, Inc.
   5    Contributed by Jason Merrill (jason@cygnus.com).
   6
   7 This file is part of GNU CC.
   8
   9 GNU CC is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2, or (at your option)
  12 any later version.
  13
  14 GNU CC is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GNU CC; see the file COPYING.  If not, write to
  21 the Free Software Foundation, 59 Temple Place - Suite 330,
  22 Boston, MA 02111-1307, USA.  */
  23
  24 #include "config.h"
  25 #include "system.h"
  26 #include "hash.h"
  27 #include "demangle.h"
  28 #include "collect2.h"
  29
  30 #define MAX_ITERATIONS 17
  31
  32 /* Obstack allocation and deallocation routines.  */
  33 #define obstack_chunk_alloc xmalloc
  34 #define obstack_chunk_free free
  35
  36 /* Defined in the automatically-generated underscore.c.  */
  37 extern int prepends_underscore;
  38
  39 static int tlink_verbose;
  40 \f
  41 /* Hash table boilerplate for working with hash.[ch].  We have hash tables
  42    for symbol names, file names, and demangled symbols.  */
  43
  44 typedef struct symbol_hash_entry
  45 {
  46   struct hash_entry root;
  47   struct file_hash_entry *file;
  48   int chosen;
  49   int tweaking;
  50   int tweaked;
  51 } symbol;
  52
  53 typedef struct file_hash_entry
  54 {
  55   struct hash_entry root;
  56   const char *args;
  57   const char *dir;
  58   const char *main;
  59   int tweaking;
  60 } file;
  61
  62 typedef struct demangled_hash_entry
  63 {
  64   struct hash_entry root;
  65   const char *mangled;
  66 } demangled;
  67
  68 static struct hash_table symbol_table;
  69
  70 static struct hash_entry * symbol_hash_newfunc PARAMS ((struct hash_entry *,
  71                                                         struct hash_table *,
  72                                                         hash_table_key));
  73 static struct symbol_hash_entry * symbol_hash_lookup PARAMS ((const char *,
  74                                                               boolean));
  75 static struct hash_entry * file_hash_newfunc PARAMS ((struct hash_entry *,
  76                                                       struct hash_table *,
  77                                                       hash_table_key));
  78 static struct file_hash_entry * file_hash_lookup PARAMS ((const char *));
  79 static struct hash_entry * demangled_hash_newfunc PARAMS ((struct hash_entry *,
  80                                                            struct hash_table *,
  81                                                            hash_table_key));
  82 static struct demangled_hash_entry *
  83   demangled_hash_lookup PARAMS ((const char *, boolean));
  84 static void symbol_push PARAMS ((symbol *));
  85 static symbol * symbol_pop PARAMS ((void));
  86 static void file_push PARAMS ((file *));
  87 static file * file_pop PARAMS ((void));
  88 static void tlink_init PARAMS ((void));
  89 static int tlink_execute PARAMS ((const char *, char **, const char *));
  90 static char * frob_extension PARAMS ((const char *, const char *));
  91 static char * obstack_fgets PARAMS ((FILE *, struct obstack *));
  92 static char * tfgets PARAMS ((FILE *));
  93 static char * pfgets PARAMS ((FILE *));
  94 static void freadsym PARAMS ((FILE *, file *, int));
  95 static void read_repo_file PARAMS ((file *));
  96 static void maybe_tweak PARAMS ((char *, file *));
  97 static int recompile_files PARAMS ((void));
  98 static int read_repo_files PARAMS ((char **));
  99 static void demangle_new_symbols PARAMS ((void));
 100 static int scan_linker_output PARAMS ((const char *));
 101
 102 /* Create a new entry for the symbol hash table.
 103    Passed to hash_table_init.  */
 104
 105 static struct hash_entry *
 106 symbol_hash_newfunc (entry, table, string)
 107      struct hash_entry *entry;
 108      struct hash_table *table;
 109      hash_table_key string ATTRIBUTE_UNUSED;
 110 {
 111   struct symbol_hash_entry *ret = (struct symbol_hash_entry *) entry;
 112   if (ret == NULL)
 113     {
 114       ret = ((struct symbol_hash_entry *)
 115              hash_allocate (table, sizeof (struct symbol_hash_entry)));
 116       if (ret == NULL)
 117         return NULL;
 118     }
 119   ret->file = NULL;
 120   ret->chosen = 0;
 121   ret->tweaking = 0;
 122   ret->tweaked = 0;
 123   return (struct hash_entry *) ret;
 124 }
 125
 126 /* Look up an entry in the symbol hash table.  */
 127
 128 static struct symbol_hash_entry *
 129 symbol_hash_lookup (string, create)
 130      const char *string;
 131      boolean create;
 132 {
 133   return ((struct symbol_hash_entry *)
 134           hash_lookup (&symbol_table, (const hash_table_key) string,
 135                        create, string_copy));
 136 }
 137
 138 static struct hash_table file_table;
 139
 140 /* Create a new entry for the file hash table.
 141    Passed to hash_table_init.  */
 142
 143 static struct hash_entry *
 144 file_hash_newfunc (entry, table, string)
 145      struct hash_entry *entry;
 146      struct hash_table *table;
 147      hash_table_key string ATTRIBUTE_UNUSED;
 148 {
 149    struct file_hash_entry *ret = (struct file_hash_entry *) entry;
 150   if (ret == NULL)
 151     {
 152       ret = ((struct file_hash_entry *)
 153              hash_allocate (table, sizeof (struct file_hash_entry)));
 154       if (ret == NULL)
 155         return NULL;
 156     }
 157   ret->args = NULL;
 158   ret->dir = NULL;
 159   ret->main = NULL;
 160   ret->tweaking = 0;
 161   return (struct hash_entry *) ret;
 162 }
 163
 164 /* Look up an entry in the file hash table.  */
 165
 166 static struct file_hash_entry *
 167 file_hash_lookup (string)
 168      const char *string;
 169 {
 170   return ((struct file_hash_entry *)
 171           hash_lookup (&file_table, (const hash_table_key) string, true,
 172                        string_copy));
 173 }
 174
 175 static struct hash_table demangled_table;
 176
 177 /* Create a new entry for the demangled name hash table.
 178    Passed to hash_table_init.  */
 179
 180 static struct hash_entry *
 181 demangled_hash_newfunc (entry, table, string)
 182      struct hash_entry *entry;
 183      struct hash_table *table;
 184      hash_table_key string ATTRIBUTE_UNUSED;
 185 {
 186   struct demangled_hash_entry *ret = (struct demangled_hash_entry *) entry;
 187   if (ret == NULL)
 188     {
 189       ret = ((struct demangled_hash_entry *)
 190              hash_allocate (table, sizeof (struct demangled_hash_entry)));
 191       if (ret == NULL)
 192         return NULL;
 193     }
 194   ret->mangled = NULL;
 195   return (struct hash_entry *) ret;
 196 }
 197
 198 /* Look up an entry in the demangled name hash table.  */
 199
 200 static struct demangled_hash_entry *
 201 demangled_hash_lookup (string, create)
 202      const char *string;
 203      boolean create;
 204 {
 205   return ((struct demangled_hash_entry *)
 206           hash_lookup (&demangled_table, (const hash_table_key) string,
 207                        create, string_copy));
 208 }
 209 \f
 210 /* Stack code.  */
 211
 212 struct symbol_stack_entry
 213 {
 214   symbol *value;
 215   struct symbol_stack_entry *next;
 216 };
 217 struct obstack symbol_stack_obstack;
 218 struct symbol_stack_entry *symbol_stack;
 219
 220 struct file_stack_entry
 221 {
 222   file *value;
 223   struct file_stack_entry *next;
 224 };
 225 struct obstack file_stack_obstack;
 226 struct file_stack_entry *file_stack;
 227
 228 static void
 229 symbol_push (p)
 230      symbol *p;
 231 {
 232   struct symbol_stack_entry *ep = (struct symbol_stack_entry *) obstack_alloc
 233     (&symbol_stack_obstack, sizeof (struct symbol_stack_entry));
 234   ep->value = p;
 235   ep->next = symbol_stack;
 236   symbol_stack = ep;
 237 }
 238
 239 static symbol *
 240 symbol_pop ()
 241 {
 242   struct symbol_stack_entry *ep = symbol_stack;
 243   symbol *p;
 244   if (ep == NULL)
 245     return NULL;
 246   p = ep->value;
 247   symbol_stack = ep->next;
 248   obstack_free (&symbol_stack_obstack, ep);
 249   return p;
 250 }
 251
 252 static void
 253 file_push (p)
 254      file *p;
 255 {
 256   struct file_stack_entry *ep;
 257
 258   if (p->tweaking)
 259     return;
 260
 261   ep = (struct file_stack_entry *) obstack_alloc
 262     (&file_stack_obstack, sizeof (struct file_stack_entry));
 263   ep->value = p;
 264   ep->next = file_stack;
 265   file_stack = ep;
 266   p->tweaking = 1;
 267 }
 268
 269 static file *
 270 file_pop ()
 271 {
 272   struct file_stack_entry *ep = file_stack;
 273   file *p;
 274   if (ep == NULL)
 275     return NULL;
 276   p = ep->value;
 277   file_stack = ep->next;
 278   obstack_free (&file_stack_obstack, ep);
 279   p->tweaking = 0;
 280   return p;
 281 }
 282 \f
 283 /* Other machinery.  */
 284
 285 /* Initialize the tlink machinery.  Called from do_tlink.  */
 286
 287 static void
 288 tlink_init ()
 289 {
 290   const char *p;
 291
 292   hash_table_init (&symbol_table, symbol_hash_newfunc, string_hash,
 293                    string_compare);
 294   hash_table_init (&file_table, file_hash_newfunc, string_hash,
 295                    string_compare);
 296   hash_table_init (&demangled_table, demangled_hash_newfunc,
 297                    string_hash, string_compare);
 298   obstack_begin (&symbol_stack_obstack, 0);
 299   obstack_begin (&file_stack_obstack, 0);
 300
 301   p = getenv ("TLINK_VERBOSE");
 302   if (p)
 303     tlink_verbose = atoi (p);
 304   else
 305     {
 306       tlink_verbose = 1;
 307       if (vflag)
 308         tlink_verbose = 2;
 309       if (debug)
 310         tlink_verbose = 3;
 311     }
 312 }
 313
 314 static int
 315 tlink_execute (prog, argv, redir)
 316      const char *prog;
 317      char **argv;
 318      const char *redir;
 319 {
 320   collect_execute (prog, argv, redir);
 321   return collect_wait (prog);
 322 }
 323
 324 static char *
 325 frob_extension (s, ext)
 326      const char *s;
 327      const char *ext;
 328 {
 329   const char *p = rindex (s, '/');
 330   if (! p)
 331     p = s;
 332   p = rindex (p, '.');
 333   if (! p)
 334     p = s + strlen (s);
 335
 336   obstack_grow (&temporary_obstack, s, p - s);
 337   return obstack_copy0 (&temporary_obstack, ext, strlen (ext));
 338 }
 339
 340 static char *
 341 obstack_fgets (stream, ob)
 342      FILE *stream;
 343      struct obstack *ob;
 344 {
 345   int c;
 346   while ((c = getc (stream)) != EOF && c != '\n')
 347     obstack_1grow (ob, c);
 348   if (obstack_object_size (ob) == 0)
 349     return NULL;
 350   obstack_1grow (ob, '\0');
 351   return obstack_finish (ob);
 352 }
 353
 354 static char *
 355 tfgets (stream)
 356      FILE *stream;
 357 {
 358   return obstack_fgets (stream, &temporary_obstack);
 359 }
 360
 361 static char *
 362 pfgets (stream)
 363      FILE *stream;
 364 {
 365   return obstack_fgets (stream, &permanent_obstack);
 366 }
 367 \f
 368 /* Real tlink code.  */
 369
 370 /* Subroutine of read_repo_file.  We are reading the repo file for file F,
 371    which is coming in on STREAM, and the symbol that comes next in STREAM
 372    is offerred, chosen or provided if CHOSEN is 0, 1 or 2, respectively.
 373
 374    XXX "provided" is unimplemented, both here and in the compiler.  */
 375
 376 static void
 377 freadsym (stream, f, chosen)
 378      FILE *stream;
 379      file *f;
 380      int chosen;
 381 {
 382   symbol *sym;
 383
 384   {
 385     const char *name = tfgets (stream);
 386     sym = symbol_hash_lookup (name, true);
 387   }
 388
 389   if (sym->file == NULL)
 390     {
 391       /* We didn't have this symbol already, so we choose this file.  */
 392
 393       symbol_push (sym);
 394       sym->file = f;
 395       sym->chosen = chosen;
 396     }
 397   else if (chosen)
 398     {
 399       /* We want this file; cast aside any pretender.  */
 400
 401       if (sym->chosen && sym->file != f)
 402         {
 403           if (sym->chosen == 1)
 404             file_push (sym->file);
 405           else
 406             {
 407               file_push (f);
 408               f = sym->file;
 409               chosen = sym->chosen;
 410             }
 411         }
 412       sym->file = f;
 413       sym->chosen = chosen;
 414     }
 415 }
 416
 417 /* Read in the repo file denoted by F, and record all its information.  */
 418
 419 static void
 420 read_repo_file (f)
 421      file *f;
 422 {
 423   char c;
 424   FILE *stream = fopen ((char*) f->root.key, "r");
 425
 426   if (tlink_verbose >= 2)
 427     fprintf (stderr, "collect: reading %s\n",
 428              (char*) f->root.key);
 429
 430   while (fscanf (stream, "%c ", &c) == 1)
 431     {
 432       switch (c)
 433         {
 434         case 'A':
 435           f->args = pfgets (stream);
 436           break;
 437         case 'D':
 438           f->dir = pfgets (stream);
 439           break;
 440         case 'M':
 441           f->main = pfgets (stream);
 442           break;
 443         case 'P':
 444           freadsym (stream, f, 2);
 445           break;
 446         case 'C':
 447           freadsym (stream, f, 1);
 448           break;
 449         case 'O':
 450           freadsym (stream, f, 0);
 451           break;
 452         }
 453       obstack_free (&temporary_obstack, temporary_firstobj);
 454     }
 455   fclose (stream);
 456   if (f->args == NULL)
 457     f->args = getenv ("COLLECT_GCC_OPTIONS");
 458   if (f->dir == NULL)
 459     f->dir = ".";
 460 }
 461
 462 /* We might want to modify LINE, which is a symbol line from file F.  We do
 463    this if either we saw an error message referring to the symbol in
 464    question, or we have already allocated the symbol to another file and
 465    this one wants to emit it as well.  */
 466
 467 static void
 468 maybe_tweak (line, f)
 469      char *line;
 470      file *f;
 471 {
 472   symbol *sym = symbol_hash_lookup (line + 2, false);
 473
 474   if ((sym->file == f && sym->tweaking)
 475       || (sym->file != f && line[0] == 'C'))
 476     {
 477       sym->tweaking = 0;
 478       sym->tweaked = 1;
 479
 480       if (line[0] == 'O')
 481         line[0] = 'C';
 482       else
 483         line[0] = 'O';
 484     }
 485 }
 486
 487 /* Update the repo files for each of the object files we have adjusted and
 488    recompile.
 489
 490    XXX Should this use collect_execute instead of system?  */
 491
 492 static int
 493 recompile_files ()
 494 {
 495   file *f;
 496
 497   while ((f = file_pop ()) != NULL)
 498     {
 499       char *line, *command;
 500       FILE *stream = fopen ((char*) f->root.key, "r");
 501       const char *outname = frob_extension ((char*) f->root.key, ".rnw");
 502       FILE *output = fopen (outname, "w");
 503
 504       while ((line = tfgets (stream)) != NULL)
 505         {
 506           switch (line[0])
 507             {
 508             case 'C':
 509             case 'O':
 510               maybe_tweak (line, f);
 511             }
 512           fprintf (output, "%s\n", line);
 513         }
 514       fclose (stream);
 515       fclose (output);
 516       rename (outname, (char*) f->root.key);
 517
 518       obstack_grow (&temporary_obstack, "cd ", 3);
 519       obstack_grow (&temporary_obstack, f->dir, strlen (f->dir));
 520       obstack_grow (&temporary_obstack, "; ", 2);
 521       obstack_grow (&temporary_obstack, c_file_name, strlen (c_file_name));
 522       obstack_1grow (&temporary_obstack, ' ');
 523       obstack_grow (&temporary_obstack, f->args, strlen (f->args));
 524       obstack_1grow (&temporary_obstack, ' ');
 525       command = obstack_copy0 (&temporary_obstack, f->main, strlen (f->main));
 526
 527       if (tlink_verbose)
 528         fprintf (stderr, "collect: recompiling %s\n", f->main);
 529       if (tlink_verbose >= 3)
 530         fprintf (stderr, "%s\n", command);
 531
 532       if (system (command) != 0)
 533         return 0;
 534
 535       read_repo_file (f);
 536
 537       obstack_free (&temporary_obstack, temporary_firstobj);
 538     }
 539   return 1;
 540 }
 541
 542 /* The first phase of processing: determine which object files have
 543    .rpo files associated with them, and read in the information.  */
 544
 545 static int
 546 read_repo_files (object_lst)
 547      char **object_lst;
 548 {
 549   char **object = object_lst;
 550
 551   for (; *object; object++)
 552     {
 553       const char *p = frob_extension (*object, ".rpo");
 554       file *f;
 555
 556       if (! file_exists (p))
 557         continue;
 558
 559       f = file_hash_lookup (p);
 560
 561       read_repo_file (f);
 562     }
 563
 564   if (file_stack != NULL && ! recompile_files ())
 565     return 0;
 566
 567   return (symbol_stack != NULL);
 568 }
 569
 570 /* Add the demangled forms of any new symbols to the hash table.  */
 571
 572 static void
 573 demangle_new_symbols ()
 574 {
 575   symbol *sym;
 576
 577   while ((sym = symbol_pop ()) != NULL)
 578     {
 579       demangled *dem;
 580       const char *p = cplus_demangle ((char*) sym->root.key,
 581                                 DMGL_PARAMS | DMGL_ANSI);
 582
 583       if (! p)
 584         continue;
 585
 586       dem = demangled_hash_lookup (p, true);
 587       dem->mangled = (char*) sym->root.key;
 588     }
 589 }
 590
 591 /* Step through the output of the linker, in the file named FNAME, and
 592    adjust the settings for each symbol encountered.  */
 593
 594 static int
 595 scan_linker_output (fname)
 596      const char *fname;
 597 {
 598   FILE *stream = fopen (fname, "r");
 599   char *line;
 600
 601   while ((line = tfgets (stream)) != NULL)
 602     {
 603       char *p = line, *q;
 604       symbol *sym;
 605       int end;
 606
 607       while (*p && ISSPACE ((unsigned char)*p))
 608         ++p;
 609
 610       if (! *p)
 611         continue;
 612
 613       for (q = p; *q && ! ISSPACE ((unsigned char)*q); ++q)
 614         ;
 615
 616       /* Try the first word on the line.  */
 617       if (*p == '.')
 618         ++p;
 619       if (*p == '_' && prepends_underscore)
 620         ++p;
 621
 622       end = ! *q;
 623       *q = 0;
 624       sym = symbol_hash_lookup (p, false);
 625
 626       if (! sym && ! end)
 627         /* Try a mangled name in quotes.  */
 628         {
 629           const char *oldq = q+1;
 630           demangled *dem = 0;
 631           q = 0;
 632
 633           /* First try `GNU style'.  */
 634           p = index (oldq, '`');
 635           if (p)
 636             p++, q = index (p, '\'');
 637           /* Then try "double quotes".  */
 638           else if (p = index (oldq, '"'), p)
 639             p++, q = index (p, '"');
 640
 641           /* We need to check for certain error keywords here, or we would
 642              mistakenly use GNU ld's "In function `foo':" message.  */
 643           if (q && (strstr (oldq, "ndefined")
 644                     || strstr (oldq, "nresolved")
 645                     || strstr (oldq, "ultiple")))
 646             {
 647               *q = 0;
 648               dem = demangled_hash_lookup (p, false);
 649               if (dem)
 650                 sym = symbol_hash_lookup (dem->mangled, false);
 651               else
 652                 {
 653                   if (*p == '_' && prepends_underscore)
 654                     ++p;
 655                   sym = symbol_hash_lookup (p, false);
 656                 }
 657             }
 658         }
 659
 660       if (sym && sym->tweaked)
 661         {
 662           fclose (stream);
 663           return 0;
 664         }
 665       if (sym && !sym->tweaking)
 666         {
 667           if (tlink_verbose >= 2)
 668             fprintf (stderr, "collect: tweaking %s in %s\n",
 669                      (char*) sym->root.key, (char*) sym->file->root.key);
 670           sym->tweaking = 1;
 671           file_push (sym->file);
 672         }
 673
 674       obstack_free (&temporary_obstack, temporary_firstobj);
 675     }
 676
 677   fclose (stream);
 678   return (file_stack != NULL);
 679 }
 680
 681 /* Entry point for tlink.  Called from main in collect2.c.
 682
 683    Iteratively try to provide definitions for all the unresolved symbols
 684    mentioned in the linker error messages.
 685
 686    LD_ARGV is an array of arguments for the linker.
 687    OBJECT_LST is an array of object files that we may be able to recompile
 688      to provide missing definitions.  Currently ignored.  */
 689
 690 void
 691 do_tlink (ld_argv, object_lst)
 692      char **ld_argv, **object_lst ATTRIBUTE_UNUSED;
 693 {
 694   int exit = tlink_execute ("ld", ld_argv, ldout);
 695
 696   tlink_init ();
 697
 698   if (exit)
 699     {
 700       int i = 0;
 701
 702       /* Until collect does a better job of figuring out which are object
 703          files, assume that everything on the command line could be.  */
 704       if (read_repo_files (ld_argv))
 705         while (exit && i++ < MAX_ITERATIONS)
 706           {
 707             if (tlink_verbose >= 3)
 708               dump_file (ldout);
 709             demangle_new_symbols ();
 710             if (! scan_linker_output (ldout))
 711               break;
 712             if (! recompile_files ())
 713               break;
 714             if (tlink_verbose)
 715               fprintf (stderr, "collect: relinking\n");
 716             exit = tlink_execute ("ld", ld_argv, ldout);
 717           }
 718     }
 719
 720   dump_file (ldout);
 721   unlink (ldout);
 722   if (exit)
 723     {
 724       error ("ld returned %d exit status", exit);
 725       collect_exit (exit);
 726     }
 727 }