gdb/block.c

   1 /* Block-related functions for the GNU debugger, GDB.
   2
   3    Copyright (C) 2003-2018 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 "block.h"
  22 #include "symtab.h"
  23 #include "symfile.h"
  24 #include "gdb_obstack.h"
  25 #include "cp-support.h"
  26 #include "addrmap.h"
  27 #include "gdbtypes.h"
  28 #include "objfiles.h"
  29
  30 /* This is used by struct block to store namespace-related info for
  31    C++ files, namely using declarations and the current namespace in
  32    scope.  */
  33
  34 struct block_namespace_info : public allocate_on_obstack
  35 {
  36   const char *scope = nullptr;
  37   struct using_direct *using_decl = nullptr;
  38 };
  39
  40 static void block_initialize_namespace (struct block *block,
  41                                         struct obstack *obstack);
  42
  43 /* See block.h.  */
  44
  45 struct objfile *
  46 block_objfile (const struct block *block)
  47 {
  48   const struct global_block *global_block;
  49
  50   if (BLOCK_FUNCTION (block) != NULL)
  51     return symbol_objfile (BLOCK_FUNCTION (block));
  52
  53   global_block = (struct global_block *) block_global_block (block);
  54   return COMPUNIT_OBJFILE (global_block->compunit_symtab);
  55 }
  56
  57 /* See block.  */
  58
  59 struct gdbarch *
  60 block_gdbarch (const struct block *block)
  61 {
  62   if (BLOCK_FUNCTION (block) != NULL)
  63     return symbol_arch (BLOCK_FUNCTION (block));
  64
  65   return get_objfile_arch (block_objfile (block));
  66 }
  67
  68 /* Return Nonzero if block a is lexically nested within block b,
  69    or if a and b have the same pc range.
  70    Return zero otherwise.  */
  71
  72 int
  73 contained_in (const struct block *a, const struct block *b)
  74 {
  75   if (!a || !b)
  76     return 0;
  77
  78   do
  79     {
  80       if (a == b)
  81         return 1;
  82       /* If A is a function block, then A cannot be contained in B,
  83          except if A was inlined.  */
  84       if (BLOCK_FUNCTION (a) != NULL && !block_inlined_p (a))
  85         return 0;
  86       a = BLOCK_SUPERBLOCK (a);
  87     }
  88   while (a != NULL);
  89
  90   return 0;
  91 }
  92
  93
  94 /* Return the symbol for the function which contains a specified
  95    lexical block, described by a struct block BL.  The return value
  96    will not be an inlined function; the containing function will be
  97    returned instead.  */
  98
  99 struct symbol *
 100 block_linkage_function (const struct block *bl)
 101 {
 102   while ((BLOCK_FUNCTION (bl) == NULL || block_inlined_p (bl))
 103          && BLOCK_SUPERBLOCK (bl) != NULL)
 104     bl = BLOCK_SUPERBLOCK (bl);
 105
 106   return BLOCK_FUNCTION (bl);
 107 }
 108
 109 /* Return the symbol for the function which contains a specified
 110    block, described by a struct block BL.  The return value will be
 111    the closest enclosing function, which might be an inline
 112    function.  */
 113
 114 struct symbol *
 115 block_containing_function (const struct block *bl)
 116 {
 117   while (BLOCK_FUNCTION (bl) == NULL && BLOCK_SUPERBLOCK (bl) != NULL)
 118     bl = BLOCK_SUPERBLOCK (bl);
 119
 120   return BLOCK_FUNCTION (bl);
 121 }
 122
 123 /* Return one if BL represents an inlined function.  */
 124
 125 int
 126 block_inlined_p (const struct block *bl)
 127 {
 128   return BLOCK_FUNCTION (bl) != NULL && SYMBOL_INLINED (BLOCK_FUNCTION (bl));
 129 }
 130
 131 /* A helper function that checks whether PC is in the blockvector BL.
 132    It returns the containing block if there is one, or else NULL.  */
 133
 134 static struct block *
 135 find_block_in_blockvector (const struct blockvector *bl, CORE_ADDR pc)
 136 {
 137   struct block *b;
 138   int bot, top, half;
 139
 140   /* If we have an addrmap mapping code addresses to blocks, then use
 141      that.  */
 142   if (BLOCKVECTOR_MAP (bl))
 143     return (struct block *) addrmap_find (BLOCKVECTOR_MAP (bl), pc);
 144
 145   /* Otherwise, use binary search to find the last block that starts
 146      before PC.
 147      Note: GLOBAL_BLOCK is block 0, STATIC_BLOCK is block 1.
 148      They both have the same START,END values.
 149      Historically this code would choose STATIC_BLOCK over GLOBAL_BLOCK but the
 150      fact that this choice was made was subtle, now we make it explicit.  */
 151   gdb_assert (BLOCKVECTOR_NBLOCKS (bl) >= 2);
 152   bot = STATIC_BLOCK;
 153   top = BLOCKVECTOR_NBLOCKS (bl);
 154
 155   while (top - bot > 1)
 156     {
 157       half = (top - bot + 1) >> 1;
 158       b = BLOCKVECTOR_BLOCK (bl, bot + half);
 159       if (BLOCK_START (b) <= pc)
 160         bot += half;
 161       else
 162         top = bot + half;
 163     }
 164
 165   /* Now search backward for a block that ends after PC.  */
 166
 167   while (bot >= STATIC_BLOCK)
 168     {
 169       b = BLOCKVECTOR_BLOCK (bl, bot);
 170       if (BLOCK_END (b) > pc)
 171         return b;
 172       bot--;
 173     }
 174
 175   return NULL;
 176 }
 177
 178 /* Return the blockvector immediately containing the innermost lexical
 179    block containing the specified pc value and section, or 0 if there
 180    is none.  PBLOCK is a pointer to the block.  If PBLOCK is NULL, we
 181    don't pass this information back to the caller.  */
 182
 183 const struct blockvector *
 184 blockvector_for_pc_sect (CORE_ADDR pc, struct obj_section *section,
 185                          const struct block **pblock,
 186                          struct compunit_symtab *cust)
 187 {
 188   const struct blockvector *bl;
 189   struct block *b;
 190
 191   if (cust == NULL)
 192     {
 193       /* First search all symtabs for one whose file contains our pc */
 194       cust = find_pc_sect_compunit_symtab (pc, section);
 195       if (cust == NULL)
 196         return 0;
 197     }
 198
 199   bl = COMPUNIT_BLOCKVECTOR (cust);
 200
 201   /* Then search that symtab for the smallest block that wins.  */
 202   b = find_block_in_blockvector (bl, pc);
 203   if (b == NULL)
 204     return NULL;
 205
 206   if (pblock)
 207     *pblock = b;
 208   return bl;
 209 }
 210
 211 /* Return true if the blockvector BV contains PC, false otherwise.  */
 212
 213 int
 214 blockvector_contains_pc (const struct blockvector *bv, CORE_ADDR pc)
 215 {
 216   return find_block_in_blockvector (bv, pc) != NULL;
 217 }
 218
 219 /* Return call_site for specified PC in GDBARCH.  PC must match exactly, it
 220    must be the next instruction after call (or after tail call jump).  Throw
 221    NO_ENTRY_VALUE_ERROR otherwise.  This function never returns NULL.  */
 222
 223 struct call_site *
 224 call_site_for_pc (struct gdbarch *gdbarch, CORE_ADDR pc)
 225 {
 226   struct compunit_symtab *cust;
 227   void **slot = NULL;
 228
 229   /* -1 as tail call PC can be already after the compilation unit range.  */
 230   cust = find_pc_compunit_symtab (pc - 1);
 231
 232   if (cust != NULL && COMPUNIT_CALL_SITE_HTAB (cust) != NULL)
 233     slot = htab_find_slot (COMPUNIT_CALL_SITE_HTAB (cust), &pc, NO_INSERT);
 234
 235   if (slot == NULL)
 236     {
 237       struct bound_minimal_symbol msym = lookup_minimal_symbol_by_pc (pc);
 238
 239       /* DW_TAG_gnu_call_site will be missing just if GCC could not determine
 240          the call target.  */
 241       throw_error (NO_ENTRY_VALUE_ERROR,
 242                    _("DW_OP_entry_value resolving cannot find "
 243                      "DW_TAG_call_site %s in %s"),
 244                    paddress (gdbarch, pc),
 245                    (msym.minsym == NULL ? "???"
 246                     : MSYMBOL_PRINT_NAME (msym.minsym)));
 247     }
 248
 249   return (struct call_site *) *slot;
 250 }
 251
 252 /* Return the blockvector immediately containing the innermost lexical block
 253    containing the specified pc value, or 0 if there is none.
 254    Backward compatibility, no section.  */
 255
 256 const struct blockvector *
 257 blockvector_for_pc (CORE_ADDR pc, const struct block **pblock)
 258 {
 259   return blockvector_for_pc_sect (pc, find_pc_mapped_section (pc),
 260                                   pblock, NULL);
 261 }
 262
 263 /* Return the innermost lexical block containing the specified pc value
 264    in the specified section, or 0 if there is none.  */
 265
 266 const struct block *
 267 block_for_pc_sect (CORE_ADDR pc, struct obj_section *section)
 268 {
 269   const struct blockvector *bl;
 270   const struct block *b;
 271
 272   bl = blockvector_for_pc_sect (pc, section, &b, NULL);
 273   if (bl)
 274     return b;
 275   return 0;
 276 }
 277
 278 /* Return the innermost lexical block containing the specified pc value,
 279    or 0 if there is none.  Backward compatibility, no section.  */
 280
 281 const struct block *
 282 block_for_pc (CORE_ADDR pc)
 283 {
 284   return block_for_pc_sect (pc, find_pc_mapped_section (pc));
 285 }
 286
 287 /* Now come some functions designed to deal with C++ namespace issues.
 288    The accessors are safe to use even in the non-C++ case.  */
 289
 290 /* This returns the namespace that BLOCK is enclosed in, or "" if it
 291    isn't enclosed in a namespace at all.  This travels the chain of
 292    superblocks looking for a scope, if necessary.  */
 293
 294 const char *
 295 block_scope (const struct block *block)
 296 {
 297   for (; block != NULL; block = BLOCK_SUPERBLOCK (block))
 298     {
 299       if (BLOCK_NAMESPACE (block) != NULL
 300           && BLOCK_NAMESPACE (block)->scope != NULL)
 301         return BLOCK_NAMESPACE (block)->scope;
 302     }
 303
 304   return "";
 305 }
 306
 307 /* Set BLOCK's scope member to SCOPE; if needed, allocate memory via
 308    OBSTACK.  (It won't make a copy of SCOPE, however, so that already
 309    has to be allocated correctly.)  */
 310
 311 void
 312 block_set_scope (struct block *block, const char *scope,
 313                  struct obstack *obstack)
 314 {
 315   block_initialize_namespace (block, obstack);
 316
 317   BLOCK_NAMESPACE (block)->scope = scope;
 318 }
 319
 320 /* This returns the using directives list associated with BLOCK, if
 321    any.  */
 322
 323 struct using_direct *
 324 block_using (const struct block *block)
 325 {
 326   if (block == NULL || BLOCK_NAMESPACE (block) == NULL)
 327     return NULL;
 328   else
 329     return BLOCK_NAMESPACE (block)->using_decl;
 330 }
 331
 332 /* Set BLOCK's using member to USING; if needed, allocate memory via
 333    OBSTACK.  (It won't make a copy of USING, however, so that already
 334    has to be allocated correctly.)  */
 335
 336 void
 337 block_set_using (struct block *block,
 338                  struct using_direct *using_decl,
 339                  struct obstack *obstack)
 340 {
 341   block_initialize_namespace (block, obstack);
 342
 343   BLOCK_NAMESPACE (block)->using_decl = using_decl;
 344 }
 345
 346 /* If BLOCK_NAMESPACE (block) is NULL, allocate it via OBSTACK and
 347    ititialize its members to zero.  */
 348
 349 static void
 350 block_initialize_namespace (struct block *block, struct obstack *obstack)
 351 {
 352   if (BLOCK_NAMESPACE (block) == NULL)
 353     BLOCK_NAMESPACE (block) = new (obstack) struct block_namespace_info ();
 354 }
 355
 356 /* Return the static block associated to BLOCK.  Return NULL if block
 357    is NULL or if block is a global block.  */
 358
 359 const struct block *
 360 block_static_block (const struct block *block)
 361 {
 362   if (block == NULL || BLOCK_SUPERBLOCK (block) == NULL)
 363     return NULL;
 364
 365   while (BLOCK_SUPERBLOCK (BLOCK_SUPERBLOCK (block)) != NULL)
 366     block = BLOCK_SUPERBLOCK (block);
 367
 368   return block;
 369 }
 370
 371 /* Return the static block associated to BLOCK.  Return NULL if block
 372    is NULL.  */
 373
 374 const struct block *
 375 block_global_block (const struct block *block)
 376 {
 377   if (block == NULL)
 378     return NULL;
 379
 380   while (BLOCK_SUPERBLOCK (block) != NULL)
 381     block = BLOCK_SUPERBLOCK (block);
 382
 383   return block;
 384 }
 385
 386 /* Allocate a block on OBSTACK, and initialize its elements to
 387    zero/NULL.  This is useful for creating "dummy" blocks that don't
 388    correspond to actual source files.
 389
 390    Warning: it sets the block's BLOCK_DICT to NULL, which isn't a
 391    valid value.  If you really don't want the block to have a
 392    dictionary, then you should subsequently set its BLOCK_DICT to
 393    dict_create_linear (obstack, NULL).  */
 394
 395 struct block *
 396 allocate_block (struct obstack *obstack)
 397 {
 398   struct block *bl = OBSTACK_ZALLOC (obstack, struct block);
 399
 400   return bl;
 401 }
 402
 403 /* Allocate a global block.  */
 404
 405 struct block *
 406 allocate_global_block (struct obstack *obstack)
 407 {
 408   struct global_block *bl = OBSTACK_ZALLOC (obstack, struct global_block);
 409
 410   return &bl->block;
 411 }
 412
 413 /* Set the compunit of the global block.  */
 414
 415 void
 416 set_block_compunit_symtab (struct block *block, struct compunit_symtab *cu)
 417 {
 418   struct global_block *gb;
 419
 420   gdb_assert (BLOCK_SUPERBLOCK (block) == NULL);
 421   gb = (struct global_block *) block;
 422   gdb_assert (gb->compunit_symtab == NULL);
 423   gb->compunit_symtab = cu;
 424 }
 425
 426 /* See block.h.  */
 427
 428 struct dynamic_prop *
 429 block_static_link (const struct block *block)
 430 {
 431   struct objfile *objfile = block_objfile (block);
 432
 433   /* Only objfile-owned blocks that materialize top function scopes can have
 434      static links.  */
 435   if (objfile == NULL || BLOCK_FUNCTION (block) == NULL)
 436     return NULL;
 437
 438   return (struct dynamic_prop *) objfile_lookup_static_link (objfile, block);
 439 }
 440
 441 /* Return the compunit of the global block.  */
 442
 443 static struct compunit_symtab *
 444 get_block_compunit_symtab (const struct block *block)
 445 {
 446   struct global_block *gb;
 447
 448   gdb_assert (BLOCK_SUPERBLOCK (block) == NULL);
 449   gb = (struct global_block *) block;
 450   gdb_assert (gb->compunit_symtab != NULL);
 451   return gb->compunit_symtab;
 452 }
 453
 454 \f
 455
 456 /* Initialize a block iterator, either to iterate over a single block,
 457    or, for static and global blocks, all the included symtabs as
 458    well.  */
 459
 460 static void
 461 initialize_block_iterator (const struct block *block,
 462                            struct block_iterator *iter)
 463 {
 464   enum block_enum which;
 465   struct compunit_symtab *cu;
 466
 467   iter->idx = -1;
 468
 469   if (BLOCK_SUPERBLOCK (block) == NULL)
 470     {
 471       which = GLOBAL_BLOCK;
 472       cu = get_block_compunit_symtab (block);
 473     }
 474   else if (BLOCK_SUPERBLOCK (BLOCK_SUPERBLOCK (block)) == NULL)
 475     {
 476       which = STATIC_BLOCK;
 477       cu = get_block_compunit_symtab (BLOCK_SUPERBLOCK (block));
 478     }
 479   else
 480     {
 481       iter->d.block = block;
 482       /* A signal value meaning that we're iterating over a single
 483          block.  */
 484       iter->which = FIRST_LOCAL_BLOCK;
 485       return;
 486     }
 487
 488   /* If this is an included symtab, find the canonical includer and
 489      use it instead.  */
 490   while (cu->user != NULL)
 491     cu = cu->user;
 492
 493   /* Putting this check here simplifies the logic of the iterator
 494      functions.  If there are no included symtabs, we only need to
 495      search a single block, so we might as well just do that
 496      directly.  */
 497   if (cu->includes == NULL)
 498     {
 499       iter->d.block = block;
 500       /* A signal value meaning that we're iterating over a single
 501          block.  */
 502       iter->which = FIRST_LOCAL_BLOCK;
 503     }
 504   else
 505     {
 506       iter->d.compunit_symtab = cu;
 507       iter->which = which;
 508     }
 509 }
 510
 511 /* A helper function that finds the current compunit over whose static
 512    or global block we should iterate.  */
 513
 514 static struct compunit_symtab *
 515 find_iterator_compunit_symtab (struct block_iterator *iterator)
 516 {
 517   if (iterator->idx == -1)
 518     return iterator->d.compunit_symtab;
 519   return iterator->d.compunit_symtab->includes[iterator->idx];
 520 }
 521
 522 /* Perform a single step for a plain block iterator, iterating across
 523    symbol tables as needed.  Returns the next symbol, or NULL when
 524    iteration is complete.  */
 525
 526 static struct symbol *
 527 block_iterator_step (struct block_iterator *iterator, int first)
 528 {
 529   struct symbol *sym;
 530
 531   gdb_assert (iterator->which != FIRST_LOCAL_BLOCK);
 532
 533   while (1)
 534     {
 535       if (first)
 536         {
 537           struct compunit_symtab *cust
 538             = find_iterator_compunit_symtab (iterator);
 539           const struct block *block;
 540
 541           /* Iteration is complete.  */
 542           if (cust == NULL)
 543             return  NULL;
 544
 545           block = BLOCKVECTOR_BLOCK (COMPUNIT_BLOCKVECTOR (cust),
 546                                      iterator->which);
 547           sym = dict_iterator_first (BLOCK_DICT (block), &iterator->dict_iter);
 548         }
 549       else
 550         sym = dict_iterator_next (&iterator->dict_iter);
 551
 552       if (sym != NULL)
 553         return sym;
 554
 555       /* We have finished iterating the appropriate block of one
 556          symtab.  Now advance to the next symtab and begin iteration
 557          there.  */
 558       ++iterator->idx;
 559       first = 1;
 560     }
 561 }
 562
 563 /* See block.h.  */
 564
 565 struct symbol *
 566 block_iterator_first (const struct block *block,
 567                       struct block_iterator *iterator)
 568 {
 569   initialize_block_iterator (block, iterator);
 570
 571   if (iterator->which == FIRST_LOCAL_BLOCK)
 572     return dict_iterator_first (block->dict, &iterator->dict_iter);
 573
 574   return block_iterator_step (iterator, 1);
 575 }
 576
 577 /* See block.h.  */
 578
 579 struct symbol *
 580 block_iterator_next (struct block_iterator *iterator)
 581 {
 582   if (iterator->which == FIRST_LOCAL_BLOCK)
 583     return dict_iterator_next (&iterator->dict_iter);
 584
 585   return block_iterator_step (iterator, 0);
 586 }
 587
 588 /* Perform a single step for a "match" block iterator, iterating
 589    across symbol tables as needed.  Returns the next symbol, or NULL
 590    when iteration is complete.  */
 591
 592 static struct symbol *
 593 block_iter_match_step (struct block_iterator *iterator,
 594                        const lookup_name_info &name,
 595                        int first)
 596 {
 597   struct symbol *sym;
 598
 599   gdb_assert (iterator->which != FIRST_LOCAL_BLOCK);
 600
 601   while (1)
 602     {
 603       if (first)
 604         {
 605           struct compunit_symtab *cust
 606             = find_iterator_compunit_symtab (iterator);
 607           const struct block *block;
 608
 609           /* Iteration is complete.  */
 610           if (cust == NULL)
 611             return  NULL;
 612
 613           block = BLOCKVECTOR_BLOCK (COMPUNIT_BLOCKVECTOR (cust),
 614                                      iterator->which);
 615           sym = dict_iter_match_first (BLOCK_DICT (block), name,
 616                                        &iterator->dict_iter);
 617         }
 618       else
 619         sym = dict_iter_match_next (name, &iterator->dict_iter);
 620
 621       if (sym != NULL)
 622         return sym;
 623
 624       /* We have finished iterating the appropriate block of one
 625          symtab.  Now advance to the next symtab and begin iteration
 626          there.  */
 627       ++iterator->idx;
 628       first = 1;
 629     }
 630 }
 631
 632 /* See block.h.  */
 633
 634 struct symbol *
 635 block_iter_match_first (const struct block *block,
 636                         const lookup_name_info &name,
 637                         struct block_iterator *iterator)
 638 {
 639   initialize_block_iterator (block, iterator);
 640
 641   if (iterator->which == FIRST_LOCAL_BLOCK)
 642     return dict_iter_match_first (block->dict, name, &iterator->dict_iter);
 643
 644   return block_iter_match_step (iterator, name, 1);
 645 }
 646
 647 /* See block.h.  */
 648
 649 struct symbol *
 650 block_iter_match_next (const lookup_name_info &name,
 651                        struct block_iterator *iterator)
 652 {
 653   if (iterator->which == FIRST_LOCAL_BLOCK)
 654     return dict_iter_match_next (name, &iterator->dict_iter);
 655
 656   return block_iter_match_step (iterator, name, 0);
 657 }
 658
 659 /* See block.h.
 660
 661    Note that if NAME is the demangled form of a C++ symbol, we will fail
 662    to find a match during the binary search of the non-encoded names, but
 663    for now we don't worry about the slight inefficiency of looking for
 664    a match we'll never find, since it will go pretty quick.  Once the
 665    binary search terminates, we drop through and do a straight linear
 666    search on the symbols.  Each symbol which is marked as being a ObjC/C++
 667    symbol (language_cplus or language_objc set) has both the encoded and
 668    non-encoded names tested for a match.  */
 669
 670 struct symbol *
 671 block_lookup_symbol (const struct block *block, const char *name,
 672                      symbol_name_match_type match_type,
 673                      const domain_enum domain)
 674 {
 675   struct block_iterator iter;
 676   struct symbol *sym;
 677
 678   lookup_name_info lookup_name (name, match_type);
 679
 680   if (!BLOCK_FUNCTION (block))
 681     {
 682       struct symbol *other = NULL;
 683
 684       ALL_BLOCK_SYMBOLS_WITH_NAME (block, lookup_name, iter, sym)
 685         {
 686           if (SYMBOL_DOMAIN (sym) == domain)
 687             return sym;
 688           /* This is a bit of a hack, but symbol_matches_domain might ignore
 689              STRUCT vs VAR domain symbols.  So if a matching symbol is found,
 690              make sure there is no "better" matching symbol, i.e., one with
 691              exactly the same domain.  PR 16253.  */
 692           if (symbol_matches_domain (SYMBOL_LANGUAGE (sym),
 693                                      SYMBOL_DOMAIN (sym), domain))
 694             other = sym;
 695         }
 696       return other;
 697     }
 698   else
 699     {
 700       /* Note that parameter symbols do not always show up last in the
 701          list; this loop makes sure to take anything else other than
 702          parameter symbols first; it only uses parameter symbols as a
 703          last resort.  Note that this only takes up extra computation
 704          time on a match.
 705          It's hard to define types in the parameter list (at least in
 706          C/C++) so we don't do the same PR 16253 hack here that is done
 707          for the !BLOCK_FUNCTION case.  */
 708
 709       struct symbol *sym_found = NULL;
 710
 711       ALL_BLOCK_SYMBOLS_WITH_NAME (block, lookup_name, iter, sym)
 712         {
 713           if (symbol_matches_domain (SYMBOL_LANGUAGE (sym),
 714                                      SYMBOL_DOMAIN (sym), domain))
 715             {
 716               sym_found = sym;
 717               if (!SYMBOL_IS_ARGUMENT (sym))
 718                 {
 719                   break;
 720                 }
 721             }
 722         }
 723       return (sym_found);       /* Will be NULL if not found.  */
 724     }
 725 }
 726
 727 /* See block.h.  */
 728
 729 struct symbol *
 730 block_lookup_symbol_primary (const struct block *block, const char *name,
 731                              const domain_enum domain)
 732 {
 733   struct symbol *sym, *other;
 734   struct dict_iterator dict_iter;
 735
 736   lookup_name_info lookup_name (name, symbol_name_match_type::FULL);
 737
 738   /* Verify BLOCK is STATIC_BLOCK or GLOBAL_BLOCK.  */
 739   gdb_assert (BLOCK_SUPERBLOCK (block) == NULL
 740               || BLOCK_SUPERBLOCK (BLOCK_SUPERBLOCK (block)) == NULL);
 741
 742   other = NULL;
 743   for (sym = dict_iter_match_first (block->dict, lookup_name, &dict_iter);
 744        sym != NULL;
 745        sym = dict_iter_match_next (lookup_name, &dict_iter))
 746     {
 747       if (SYMBOL_DOMAIN (sym) == domain)
 748         return sym;
 749
 750       /* This is a bit of a hack, but symbol_matches_domain might ignore
 751          STRUCT vs VAR domain symbols.  So if a matching symbol is found,
 752          make sure there is no "better" matching symbol, i.e., one with
 753          exactly the same domain.  PR 16253.  */
 754       if (symbol_matches_domain (SYMBOL_LANGUAGE (sym),
 755                                  SYMBOL_DOMAIN (sym), domain))
 756         other = sym;
 757     }
 758
 759   return other;
 760 }
 761
 762 /* See block.h.  */
 763
 764 struct symbol *
 765 block_find_symbol (const struct block *block, const char *name,
 766                    const domain_enum domain,
 767                    block_symbol_matcher_ftype *matcher, void *data)
 768 {
 769   struct block_iterator iter;
 770   struct symbol *sym;
 771
 772   lookup_name_info lookup_name (name, symbol_name_match_type::FULL);
 773
 774   /* Verify BLOCK is STATIC_BLOCK or GLOBAL_BLOCK.  */
 775   gdb_assert (BLOCK_SUPERBLOCK (block) == NULL
 776               || BLOCK_SUPERBLOCK (BLOCK_SUPERBLOCK (block)) == NULL);
 777
 778   ALL_BLOCK_SYMBOLS_WITH_NAME (block, lookup_name, iter, sym)
 779     {
 780       /* MATCHER is deliberately called second here so that it never sees
 781          a non-domain-matching symbol.  */
 782       if (symbol_matches_domain (SYMBOL_LANGUAGE (sym),
 783                                  SYMBOL_DOMAIN (sym), domain)
 784           && matcher (sym, data))
 785         return sym;
 786     }
 787   return NULL;
 788 }
 789
 790 /* See block.h.  */
 791
 792 int
 793 block_find_non_opaque_type (struct symbol *sym, void *data)
 794 {
 795   return !TYPE_IS_OPAQUE (SYMBOL_TYPE (sym));
 796 }
 797
 798 /* See block.h.  */
 799
 800 int
 801 block_find_non_opaque_type_preferred (struct symbol *sym, void *data)
 802 {
 803   struct symbol **best = (struct symbol **) data;
 804
 805   if (!TYPE_IS_OPAQUE (SYMBOL_TYPE (sym)))
 806     return 1;
 807   *best = sym;
 808   return 0;
 809 }