xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/cp-namespace.c (revision 0ab5b340411a90c5db2463a3bd38d565fa784c5c)
1 /* Helper routines for C++ support in GDB.
2    Copyright (C) 2003-2014 Free Software Foundation, Inc.
3 
4    Contributed by David Carlton and by Kealia, Inc.
5 
6    This file is part of GDB.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20 
21 #include "defs.h"
22 #include "cp-support.h"
23 #include "gdb_obstack.h"
24 #include "symtab.h"
25 #include "symfile.h"
26 #include "gdb_assert.h"
27 #include "block.h"
28 #include "objfiles.h"
29 #include "gdbtypes.h"
30 #include "dictionary.h"
31 #include "command.h"
32 #include "frame.h"
33 #include "buildsym.h"
34 #include "language.h"
35 
36 static struct symbol *lookup_namespace_scope (const char *name,
37 					      const struct block *block,
38 					      const domain_enum domain,
39 					      const char *scope,
40 					      int scope_len);
41 
42 static struct symbol *lookup_symbol_file (const char *name,
43 					  const struct block *block,
44 					  const domain_enum domain,
45 					  int anonymous_namespace,
46 					  int search);
47 
48 static struct type *cp_lookup_transparent_type_loop (const char *name,
49 						     const char *scope,
50 						     int scope_len);
51 
52 /* Check to see if SYMBOL refers to an object contained within an
53    anonymous namespace; if so, add an appropriate using directive.  */
54 
55 void
56 cp_scan_for_anonymous_namespaces (const struct symbol *const symbol,
57 				  struct objfile *const objfile)
58 {
59   if (SYMBOL_DEMANGLED_NAME (symbol) != NULL)
60     {
61       const char *name = SYMBOL_DEMANGLED_NAME (symbol);
62       unsigned int previous_component;
63       unsigned int next_component;
64 
65       /* Start with a quick-and-dirty check for mention of "(anonymous
66 	 namespace)".  */
67 
68       if (!cp_is_anonymous (name))
69 	return;
70 
71       previous_component = 0;
72       next_component = cp_find_first_component (name + previous_component);
73 
74       while (name[next_component] == ':')
75 	{
76 	  if (((next_component - previous_component)
77 	       == CP_ANONYMOUS_NAMESPACE_LEN)
78 	      && strncmp (name + previous_component,
79 			  CP_ANONYMOUS_NAMESPACE_STR,
80 			  CP_ANONYMOUS_NAMESPACE_LEN) == 0)
81 	    {
82 	      int dest_len = (previous_component == 0
83 			      ? 0 : previous_component - 2);
84 	      int src_len = next_component;
85 
86 	      char *dest = alloca (dest_len + 1);
87 	      char *src = alloca (src_len + 1);
88 
89 	      memcpy (dest, name, dest_len);
90 	      memcpy (src, name, src_len);
91 
92 	      dest[dest_len] = '\0';
93 	      src[src_len] = '\0';
94 
95 	      /* We've found a component of the name that's an
96 		 anonymous namespace.  So add symbols in it to the
97 		 namespace given by the previous component if there is
98 		 one, or to the global namespace if there isn't.  */
99 	      cp_add_using_directive (dest, src, NULL, NULL, NULL, 1,
100 	                              &objfile->objfile_obstack);
101 	    }
102 	  /* The "+ 2" is for the "::".  */
103 	  previous_component = next_component + 2;
104 	  next_component = (previous_component
105 			    + cp_find_first_component (name
106 						       + previous_component));
107 	}
108     }
109 }
110 
111 
112 /* Add a using directive to using_directives.  If the using directive
113    in question has already been added, don't add it twice.
114 
115    Create a new struct using_direct which imports the namespace SRC
116    into the scope DEST.  ALIAS is the name of the imported namespace
117    in the current scope.  If ALIAS is NULL then the namespace is known
118    by its original name.  DECLARATION is the name if the imported
119    varable if this is a declaration import (Eg. using A::x), otherwise
120    it is NULL.  EXCLUDES is a list of names not to import from an
121    imported module or NULL.  If COPY_NAMES is non-zero, then the
122    arguments are copied into newly allocated memory so they can be
123    temporaries.  For EXCLUDES the VEC pointers are copied but the
124    pointed to characters are not copied.  */
125 
126 void
127 cp_add_using_directive (const char *dest,
128 			const char *src,
129 			const char *alias,
130 			const char *declaration,
131 			VEC (const_char_ptr) *excludes,
132 			int copy_names,
133                         struct obstack *obstack)
134 {
135   struct using_direct *current;
136   struct using_direct *new;
137 
138   /* Has it already been added?  */
139 
140   for (current = using_directives; current != NULL; current = current->next)
141     {
142       int ix;
143       const char *param;
144 
145       if (strcmp (current->import_src, src) != 0)
146 	continue;
147       if (strcmp (current->import_dest, dest) != 0)
148 	continue;
149       if ((alias == NULL && current->alias != NULL)
150 	  || (alias != NULL && current->alias == NULL)
151 	  || (alias != NULL && current->alias != NULL
152 	      && strcmp (alias, current->alias) != 0))
153 	continue;
154       if ((declaration == NULL && current->declaration != NULL)
155 	  || (declaration != NULL && current->declaration == NULL)
156 	  || (declaration != NULL && current->declaration != NULL
157 	      && strcmp (declaration, current->declaration) != 0))
158 	continue;
159 
160       /* Compare the contents of EXCLUDES.  */
161       for (ix = 0; VEC_iterate (const_char_ptr, excludes, ix, param); ix++)
162 	if (current->excludes[ix] == NULL
163 	    || strcmp (param, current->excludes[ix]) != 0)
164 	  break;
165       if (ix < VEC_length (const_char_ptr, excludes)
166 	  || current->excludes[ix] != NULL)
167 	continue;
168 
169       /* Parameters exactly match CURRENT.  */
170       return;
171     }
172 
173   new = obstack_alloc (obstack, (sizeof (*new)
174 				 + (VEC_length (const_char_ptr, excludes)
175 				    * sizeof (*new->excludes))));
176   memset (new, 0, sizeof (*new));
177 
178   if (copy_names)
179     {
180       new->import_src = obstack_copy0 (obstack, src, strlen (src));
181       new->import_dest = obstack_copy0 (obstack, dest, strlen (dest));
182     }
183   else
184     {
185       new->import_src = src;
186       new->import_dest = dest;
187     }
188 
189   if (alias != NULL && copy_names)
190     new->alias = obstack_copy0 (obstack, alias, strlen (alias));
191   else
192     new->alias = alias;
193 
194   if (declaration != NULL && copy_names)
195     new->declaration = obstack_copy0 (obstack,
196 				      declaration, strlen (declaration));
197   else
198     new->declaration = declaration;
199 
200   memcpy (new->excludes, VEC_address (const_char_ptr, excludes),
201 	  VEC_length (const_char_ptr, excludes) * sizeof (*new->excludes));
202   new->excludes[VEC_length (const_char_ptr, excludes)] = NULL;
203 
204   new->next = using_directives;
205   using_directives = new;
206 }
207 
208 /* Test whether or not NAMESPACE looks like it mentions an anonymous
209    namespace; return nonzero if so.  */
210 
211 int
212 cp_is_anonymous (const char *namespace)
213 {
214   return (strstr (namespace, CP_ANONYMOUS_NAMESPACE_STR)
215 	  != NULL);
216 }
217 
218 /* The C++-specific version of name lookup for static and global
219    names.  This makes sure that names get looked for in all namespaces
220    that are in scope.  NAME is the natural name of the symbol that
221    we're looking for, BLOCK is the block that we're searching within,
222    DOMAIN says what kind of symbols we're looking for, and if SYMTAB
223    is non-NULL, we should store the symtab where we found the symbol
224    in it.  */
225 
226 struct symbol *
227 cp_lookup_symbol_nonlocal (const char *name,
228 			   const struct block *block,
229 			   const domain_enum domain)
230 {
231   struct symbol *sym;
232   const char *scope = block_scope (block);
233 
234   sym = lookup_namespace_scope (name, block,
235 				domain, scope, 0);
236   if (sym != NULL)
237     return sym;
238 
239   return cp_lookup_symbol_namespace (scope, name,
240 				     block, domain);
241 }
242 
243 /* Look up NAME in the C++ namespace NAMESPACE.  Other arguments are
244    as in cp_lookup_symbol_nonlocal.  If SEARCH is non-zero, search
245    through base classes for a matching symbol.  */
246 
247 static struct symbol *
248 cp_lookup_symbol_in_namespace (const char *namespace,
249                                const char *name,
250                                const struct block *block,
251                                const domain_enum domain, int search)
252 {
253   if (namespace[0] == '\0')
254     {
255       return lookup_symbol_file (name, block, domain, 0, search);
256     }
257   else
258     {
259       char *concatenated_name = alloca (strlen (namespace) + 2
260 					+ strlen (name) + 1);
261 
262       strcpy (concatenated_name, namespace);
263       strcat (concatenated_name, "::");
264       strcat (concatenated_name, name);
265       return lookup_symbol_file (concatenated_name, block, domain,
266 				 cp_is_anonymous (namespace), search);
267     }
268 }
269 
270 /* Used for cleanups to reset the "searched" flag incase
271    of an error.  */
272 
273 static void
274 reset_directive_searched (void *data)
275 {
276   struct using_direct *direct = data;
277   direct->searched = 0;
278 }
279 
280 /* Search for NAME by applying all import statements belonging to
281    BLOCK which are applicable in SCOPE.  If DECLARATION_ONLY the
282    search is restricted to using declarations.
283    Example:
284 
285      namespace A {
286        int x;
287      }
288      using A::x;
289 
290    If SEARCH_PARENTS the search will include imports which are
291    applicable in parents of SCOPE.
292    Example:
293 
294      namespace A {
295        using namespace X;
296        namespace B {
297          using namespace Y;
298        }
299      }
300 
301    If SCOPE is "A::B" and SEARCH_PARENTS is true the imports of
302    namespaces X and Y will be considered.  If SEARCH_PARENTS is false
303    only the import of Y is considered.  */
304 
305 struct symbol *
306 cp_lookup_symbol_imports (const char *scope,
307                           const char *name,
308                           const struct block *block,
309                           const domain_enum domain,
310                           const int declaration_only,
311                           const int search_parents)
312 {
313   struct using_direct *current;
314   struct symbol *sym = NULL;
315   int len;
316   int directive_match;
317   struct cleanup *searched_cleanup;
318 
319   /* First, try to find the symbol in the given namespace.  */
320   if (!declaration_only)
321     sym = cp_lookup_symbol_in_namespace (scope, name,
322 					 block, domain, 1);
323 
324   if (sym != NULL)
325     return sym;
326 
327   /* Go through the using directives.  If any of them add new names to
328      the namespace we're searching in, see if we can find a match by
329      applying them.  */
330 
331   for (current = block_using (block);
332        current != NULL;
333        current = current->next)
334     {
335       const char **excludep;
336 
337       len = strlen (current->import_dest);
338       directive_match = (search_parents
339                          ? (strncmp (scope, current->import_dest,
340                                      strlen (current->import_dest)) == 0
341                             && (len == 0
342                                 || scope[len] == ':'
343 				|| scope[len] == '\0'))
344                          : strcmp (scope, current->import_dest) == 0);
345 
346       /* If the import destination is the current scope or one of its
347          ancestors then it is applicable.  */
348       if (directive_match && !current->searched)
349 	{
350 	  /* Mark this import as searched so that the recursive call
351 	     does not search it again.  */
352 	  current->searched = 1;
353 	  searched_cleanup = make_cleanup (reset_directive_searched,
354 					   current);
355 
356 	  /* If there is an import of a single declaration, compare the
357 	     imported declaration (after optional renaming by its alias)
358 	     with the sought out name.  If there is a match pass
359 	     current->import_src as NAMESPACE to direct the search
360 	     towards the imported namespace.  */
361 	  if (current->declaration
362 	      && strcmp (name, current->alias
363 			 ? current->alias : current->declaration) == 0)
364 	    sym = cp_lookup_symbol_in_namespace (current->import_src,
365 						 current->declaration,
366 						 block, domain, 1);
367 
368 	  /* If this is a DECLARATION_ONLY search or a symbol was found
369 	     or this import statement was an import declaration, the
370 	     search of this import is complete.  */
371 	  if (declaration_only || sym != NULL || current->declaration)
372 	    {
373 	      current->searched = 0;
374 	      discard_cleanups (searched_cleanup);
375 
376 	      if (sym != NULL)
377 		return sym;
378 
379 	      continue;
380 	    }
381 
382 	  /* Do not follow CURRENT if NAME matches its EXCLUDES.  */
383 	  for (excludep = current->excludes; *excludep; excludep++)
384 	    if (strcmp (name, *excludep) == 0)
385 	      break;
386 	  if (*excludep)
387 	    {
388 	      discard_cleanups (searched_cleanup);
389 	      continue;
390 	    }
391 
392 	  if (current->alias != NULL
393 	      && strcmp (name, current->alias) == 0)
394 	    /* If the import is creating an alias and the alias matches
395 	       the sought name.  Pass current->import_src as the NAME to
396 	       direct the search towards the aliased namespace.  */
397 	    {
398 	      sym = cp_lookup_symbol_in_namespace (scope,
399 						   current->import_src,
400 						   block, domain, 1);
401 	    }
402 	  else if (current->alias == NULL)
403 	    {
404 	      /* If this import statement creates no alias, pass
405 		 current->inner as NAMESPACE to direct the search
406 		 towards the imported namespace.  */
407 	      sym = cp_lookup_symbol_imports (current->import_src,
408 					      name, block,
409 					      domain, 0, 0);
410 	    }
411 	  current->searched = 0;
412 	  discard_cleanups (searched_cleanup);
413 
414 	  if (sym != NULL)
415 	    return sym;
416 	}
417     }
418 
419   return NULL;
420 }
421 
422 /* Helper function that searches an array of symbols for one named
423    NAME.  */
424 
425 static struct symbol *
426 search_symbol_list (const char *name, int num,
427 		    struct symbol **syms)
428 {
429   int i;
430 
431   /* Maybe we should store a dictionary in here instead.  */
432   for (i = 0; i < num; ++i)
433     {
434       if (strcmp (name, SYMBOL_NATURAL_NAME (syms[i])) == 0)
435 	return syms[i];
436     }
437   return NULL;
438 }
439 
440 /* Like cp_lookup_symbol_imports, but if BLOCK is a function, it
441    searches through the template parameters of the function and the
442    function's type.  */
443 
444 struct symbol *
445 cp_lookup_symbol_imports_or_template (const char *scope,
446 				      const char *name,
447 				      const struct block *block,
448 				      const domain_enum domain)
449 {
450   struct symbol *function = BLOCK_FUNCTION (block);
451 
452   if (function != NULL && SYMBOL_LANGUAGE (function) == language_cplus)
453     {
454       /* Search the function's template parameters.  */
455       if (SYMBOL_IS_CPLUS_TEMPLATE_FUNCTION (function))
456 	{
457 	  struct template_symbol *templ
458 	    = (struct template_symbol *) function;
459 	  struct symbol *result;
460 
461 	  result = search_symbol_list (name,
462 				       templ->n_template_arguments,
463 				       templ->template_arguments);
464 	  if (result != NULL)
465 	    return result;
466 	}
467 
468       /* Search the template parameters of the function's defining
469 	 context.  */
470       if (SYMBOL_NATURAL_NAME (function))
471 	{
472 	  struct type *context;
473 	  char *name_copy = xstrdup (SYMBOL_NATURAL_NAME (function));
474 	  struct cleanup *cleanups = make_cleanup (xfree, name_copy);
475 	  const struct language_defn *lang = language_def (language_cplus);
476 	  struct gdbarch *arch
477 	    = get_objfile_arch (SYMBOL_SYMTAB (function)->objfile);
478 	  const struct block *parent = BLOCK_SUPERBLOCK (block);
479 
480 	  while (1)
481 	    {
482 	      struct symbol *result;
483 	      unsigned int prefix_len = cp_entire_prefix_len (name_copy);
484 
485 	      if (prefix_len == 0)
486 		context = NULL;
487 	      else
488 		{
489 		  name_copy[prefix_len] = '\0';
490 		  context = lookup_typename (lang, arch,
491 					     name_copy,
492 					     parent, 1);
493 		}
494 
495 	      if (context == NULL)
496 		break;
497 
498 	      result
499 		= search_symbol_list (name,
500 				      TYPE_N_TEMPLATE_ARGUMENTS (context),
501 				      TYPE_TEMPLATE_ARGUMENTS (context));
502 	      if (result != NULL)
503 		{
504 		  do_cleanups (cleanups);
505 		  return result;
506 		}
507 	    }
508 
509 	  do_cleanups (cleanups);
510 	}
511     }
512 
513   return cp_lookup_symbol_imports (scope, name, block, domain, 1, 1);
514 }
515 
516  /* Searches for NAME in the current namespace, and by applying
517     relevant import statements belonging to BLOCK and its parents.
518     SCOPE is the namespace scope of the context in which the search is
519     being evaluated.  */
520 
521 struct symbol*
522 cp_lookup_symbol_namespace (const char *scope,
523                             const char *name,
524                             const struct block *block,
525                             const domain_enum domain)
526 {
527   struct symbol *sym;
528 
529   /* First, try to find the symbol in the given namespace.  */
530   sym = cp_lookup_symbol_in_namespace (scope, name,
531 				       block, domain, 1);
532   if (sym != NULL)
533     return sym;
534 
535   /* Search for name in namespaces imported to this and parent
536      blocks.  */
537   while (block != NULL)
538     {
539       sym = cp_lookup_symbol_imports (scope, name, block,
540 				      domain, 0, 1);
541 
542       if (sym)
543 	return sym;
544 
545       block = BLOCK_SUPERBLOCK (block);
546     }
547 
548   return NULL;
549 }
550 
551 /* Lookup NAME at namespace scope (or, in C terms, in static and
552    global variables).  SCOPE is the namespace that the current
553    function is defined within; only consider namespaces whose length
554    is at least SCOPE_LEN.  Other arguments are as in
555    cp_lookup_symbol_nonlocal.
556 
557    For example, if we're within a function A::B::f and looking for a
558    symbol x, this will get called with NAME = "x", SCOPE = "A::B", and
559    SCOPE_LEN = 0.  It then calls itself with NAME and SCOPE the same,
560    but with SCOPE_LEN = 1.  And then it calls itself with NAME and
561    SCOPE the same, but with SCOPE_LEN = 4.  This third call looks for
562    "A::B::x"; if it doesn't find it, then the second call looks for
563    "A::x", and if that call fails, then the first call looks for
564    "x".  */
565 
566 static struct symbol *
567 lookup_namespace_scope (const char *name,
568 			const struct block *block,
569 			const domain_enum domain,
570 			const char *scope,
571 			int scope_len)
572 {
573   char *namespace;
574 
575   if (scope[scope_len] != '\0')
576     {
577       /* Recursively search for names in child namespaces first.  */
578 
579       struct symbol *sym;
580       int new_scope_len = scope_len;
581 
582       /* If the current scope is followed by "::", skip past that.  */
583       if (new_scope_len != 0)
584 	{
585 	  gdb_assert (scope[new_scope_len] == ':');
586 	  new_scope_len += 2;
587 	}
588       new_scope_len += cp_find_first_component (scope + new_scope_len);
589       sym = lookup_namespace_scope (name, block, domain,
590 				    scope, new_scope_len);
591       if (sym != NULL)
592 	return sym;
593     }
594 
595   /* Okay, we didn't find a match in our children, so look for the
596      name in the current namespace.  */
597 
598   namespace = alloca (scope_len + 1);
599   strncpy (namespace, scope, scope_len);
600   namespace[scope_len] = '\0';
601   return cp_lookup_symbol_in_namespace (namespace, name,
602 					block, domain, 1);
603 }
604 
605 /* Look up NAME in BLOCK's static block and in global blocks.  If
606    ANONYMOUS_NAMESPACE is nonzero, the symbol in question is located
607    within an anonymous namespace.  If SEARCH is non-zero, search through
608    base classes for a matching symbol.  Other arguments are as in
609    cp_lookup_symbol_nonlocal.  */
610 
611 static struct symbol *
612 lookup_symbol_file (const char *name,
613 		    const struct block *block,
614 		    const domain_enum domain,
615 		    int anonymous_namespace, int search)
616 {
617   struct symbol *sym = NULL;
618 
619   sym = lookup_symbol_static (name, block, domain);
620   if (sym != NULL)
621     return sym;
622 
623   if (anonymous_namespace)
624     {
625       /* Symbols defined in anonymous namespaces have external linkage
626 	 but should be treated as local to a single file nonetheless.
627 	 So we only search the current file's global block.  */
628 
629       const struct block *global_block = block_global_block (block);
630 
631       if (global_block != NULL)
632 	sym = lookup_symbol_aux_block (name, global_block, domain);
633     }
634   else
635     {
636       sym = lookup_symbol_global (name, block, domain);
637     }
638 
639   if (sym != NULL)
640     return sym;
641 
642   if (search)
643     {
644       char *klass, *nested;
645       unsigned int prefix_len;
646       struct cleanup *cleanup;
647       struct symbol *klass_sym;
648 
649       /* A simple lookup failed.  Check if the symbol was defined in
650 	 a base class.  */
651 
652       cleanup = make_cleanup (null_cleanup, NULL);
653 
654       /* Find the name of the class and the name of the method,
655 	 variable, etc.  */
656       prefix_len = cp_entire_prefix_len (name);
657 
658       /* If no prefix was found, search "this".  */
659       if (prefix_len == 0)
660 	{
661 	  struct type *type;
662 	  struct symbol *this;
663 
664 	  this = lookup_language_this (language_def (language_cplus), block);
665 	  if (this == NULL)
666 	    {
667 	      do_cleanups (cleanup);
668 	      return NULL;
669 	    }
670 
671 	  type = check_typedef (TYPE_TARGET_TYPE (SYMBOL_TYPE (this)));
672 	  klass = xstrdup (TYPE_NAME (type));
673 	  nested = xstrdup (name);
674 	}
675       else
676 	{
677 	  /* The class name is everything up to and including PREFIX_LEN.  */
678 	  klass = savestring (name, prefix_len);
679 
680 	  /* The rest of the name is everything else past the initial scope
681 	     operator.  */
682 	  nested = xstrdup (name + prefix_len + 2);
683 	}
684 
685       /* Add cleanups to free memory for these strings.  */
686       make_cleanup (xfree, klass);
687       make_cleanup (xfree, nested);
688 
689       /* Lookup a class named KLASS.  If none is found, there is nothing
690 	 more that can be done.  */
691       klass_sym = lookup_symbol_global (klass, block, domain);
692       if (klass_sym == NULL)
693 	{
694 	  do_cleanups (cleanup);
695 	  return NULL;
696 	}
697 
698       /* Look for a symbol named NESTED in this class.  */
699       sym = cp_lookup_nested_symbol (SYMBOL_TYPE (klass_sym), nested, block);
700       do_cleanups (cleanup);
701     }
702 
703   return sym;
704 }
705 
706 /* Search through the base classes of PARENT_TYPE for a base class
707    named NAME and return its type.  If not found, return NULL.  */
708 
709 struct type *
710 find_type_baseclass_by_name (struct type *parent_type, const char *name)
711 {
712   int i;
713 
714   CHECK_TYPEDEF (parent_type);
715   for (i = 0; i < TYPE_N_BASECLASSES (parent_type); ++i)
716     {
717       struct type *type = check_typedef (TYPE_BASECLASS (parent_type, i));
718       const char *base_name = TYPE_BASECLASS_NAME (parent_type, i);
719 
720       if (base_name == NULL)
721 	continue;
722 
723       if (streq (base_name, name))
724 	return type;
725 
726       type = find_type_baseclass_by_name (type, name);
727       if (type != NULL)
728 	return type;
729     }
730 
731   return NULL;
732 }
733 
734 /* Search through the base classes of PARENT_TYPE for a symbol named
735    NAME in block BLOCK.  */
736 
737 static struct symbol *
738 find_symbol_in_baseclass (struct type *parent_type, const char *name,
739 			   const struct block *block)
740 {
741   int i;
742   struct symbol *sym;
743   struct cleanup *cleanup;
744   char *concatenated_name;
745 
746   sym = NULL;
747   concatenated_name = NULL;
748   cleanup = make_cleanup (free_current_contents, &concatenated_name);
749   for (i = 0; i < TYPE_N_BASECLASSES (parent_type); ++i)
750     {
751       size_t len;
752       struct type *base_type = TYPE_BASECLASS (parent_type, i);
753       const char *base_name = TYPE_BASECLASS_NAME (parent_type, i);
754 
755       if (base_name == NULL)
756 	continue;
757 
758       /* Search this particular base class.  */
759       sym = cp_lookup_symbol_in_namespace (base_name, name, block,
760 					   VAR_DOMAIN, 0);
761       if (sym != NULL)
762 	break;
763 
764       /* Now search all static file-level symbols.  We have to do this for
765 	 things like typedefs in the class.  First search in this symtab,
766 	 what we want is possibly there.  */
767       len = strlen (base_name) + 2 + strlen (name) + 1;
768       concatenated_name = xrealloc (concatenated_name, len);
769       xsnprintf (concatenated_name, len, "%s::%s", base_name, name);
770       sym = lookup_symbol_static (concatenated_name, block, VAR_DOMAIN);
771       if (sym != NULL)
772 	break;
773 
774       /* Nope.  We now have to search all static blocks in all objfiles,
775 	 even if block != NULL, because there's no guarantees as to which
776 	 symtab the symbol we want is in.  */
777       sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
778       if (sym != NULL)
779 	break;
780 
781       /* If this class has base classes, search them next.  */
782       CHECK_TYPEDEF (base_type);
783       if (TYPE_N_BASECLASSES (base_type) > 0)
784 	{
785 	  sym = find_symbol_in_baseclass (base_type, name, block);
786 	  if (sym != NULL)
787 	    break;
788 	}
789     }
790 
791   do_cleanups (cleanup);
792   return sym;
793 }
794 
795 /* Look up a symbol named NESTED_NAME that is nested inside the C++
796    class or namespace given by PARENT_TYPE, from within the context
797    given by BLOCK.  Return NULL if there is no such nested type.  */
798 
799 struct symbol *
800 cp_lookup_nested_symbol (struct type *parent_type,
801 			 const char *nested_name,
802 			 const struct block *block)
803 {
804   /* type_name_no_tag_required provides better error reporting using the
805      original type.  */
806   struct type *saved_parent_type = parent_type;
807 
808   CHECK_TYPEDEF (parent_type);
809 
810   switch (TYPE_CODE (parent_type))
811     {
812     case TYPE_CODE_STRUCT:
813     case TYPE_CODE_NAMESPACE:
814     case TYPE_CODE_UNION:
815     /* NOTE: Handle modules here as well, because Fortran is re-using the C++
816        specific code to lookup nested symbols in modules, by calling the
817        function pointer la_lookup_symbol_nonlocal, which ends up here.  */
818     case TYPE_CODE_MODULE:
819       {
820 	/* NOTE: carlton/2003-11-10: We don't treat C++ class members
821 	   of classes like, say, data or function members.  Instead,
822 	   they're just represented by symbols whose names are
823 	   qualified by the name of the surrounding class.  This is
824 	   just like members of namespaces; in particular,
825 	   lookup_symbol_namespace works when looking them up.  */
826 
827 	int size;
828 	const char *parent_name = type_name_no_tag_or_error (saved_parent_type);
829 	struct symbol *sym
830 	  = cp_lookup_symbol_in_namespace (parent_name, nested_name,
831 					   block, VAR_DOMAIN, 0);
832 	char *concatenated_name;
833 
834 	if (sym != NULL)
835 	  return sym;
836 
837 	/* Now search all static file-level symbols.  We have to do this
838 	   for things like typedefs in the class.  We do not try to
839 	   guess any imported namespace as even the fully specified
840 	   namespace search is already not C++ compliant and more
841 	   assumptions could make it too magic.  */
842 
843 	size = strlen (parent_name) + 2 + strlen (nested_name) + 1;
844 	concatenated_name = alloca (size);
845 	xsnprintf (concatenated_name, size, "%s::%s",
846 		 parent_name, nested_name);
847 	sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
848 	if (sym != NULL)
849 	  return sym;
850 
851 	/* If no matching symbols were found, try searching any
852 	   base classes.  */
853 	return find_symbol_in_baseclass (parent_type, nested_name, block);
854       }
855 
856     case TYPE_CODE_FUNC:
857     case TYPE_CODE_METHOD:
858       return NULL;
859 
860     default:
861       internal_error (__FILE__, __LINE__,
862 		      _("cp_lookup_nested_symbol called "
863 			"on a non-aggregate type."));
864     }
865 }
866 
867 /* The C++-version of lookup_transparent_type.  */
868 
869 /* FIXME: carlton/2004-01-16: The problem that this is trying to
870    address is that, unfortunately, sometimes NAME is wrong: it may not
871    include the name of namespaces enclosing the type in question.
872    lookup_transparent_type gets called when the type in question
873    is a declaration, and we're trying to find its definition; but, for
874    declarations, our type name deduction mechanism doesn't work.
875    There's nothing we can do to fix this in general, I think, in the
876    absence of debug information about namespaces (I've filed PR
877    gdb/1511 about this); until such debug information becomes more
878    prevalent, one heuristic which sometimes looks is to search for the
879    definition in namespaces containing the current namespace.
880 
881    We should delete this functions once the appropriate debug
882    information becomes more widespread.  (GCC 3.4 will be the first
883    released version of GCC with such information.)  */
884 
885 struct type *
886 cp_lookup_transparent_type (const char *name)
887 {
888   /* First, try the honest way of looking up the definition.  */
889   struct type *t = basic_lookup_transparent_type (name);
890   const char *scope;
891 
892   if (t != NULL)
893     return t;
894 
895   /* If that doesn't work and we're within a namespace, look there
896      instead.  */
897   scope = block_scope (get_selected_block (0));
898 
899   if (scope[0] == '\0')
900     return NULL;
901 
902   return cp_lookup_transparent_type_loop (name, scope, 0);
903 }
904 
905 /* Lookup the type definition associated to NAME in namespaces/classes
906    containing SCOPE whose name is strictly longer than LENGTH.  LENGTH
907    must be the index of the start of a component of SCOPE.  */
908 
909 static struct type *
910 cp_lookup_transparent_type_loop (const char *name,
911 				 const char *scope,
912 				 int length)
913 {
914   int scope_length = length + cp_find_first_component (scope + length);
915   char *full_name;
916 
917   /* If the current scope is followed by "::", look in the next
918      component.  */
919   if (scope[scope_length] == ':')
920     {
921       struct type *retval
922 	= cp_lookup_transparent_type_loop (name, scope,
923 					   scope_length + 2);
924 
925       if (retval != NULL)
926 	return retval;
927     }
928 
929   full_name = alloca (scope_length + 2 + strlen (name) + 1);
930   strncpy (full_name, scope, scope_length);
931   strncpy (full_name + scope_length, "::", 2);
932   strcpy (full_name + scope_length + 2, name);
933 
934   return basic_lookup_transparent_type (full_name);
935 }
936 
937 /* This used to do something but was removed when it became
938    obsolete.  */
939 
940 static void
941 maintenance_cplus_namespace (char *args, int from_tty)
942 {
943   printf_unfiltered (_("The `maint namespace' command was removed.\n"));
944 }
945 
946 /* Provide a prototype to silence -Wmissing-prototypes.  */
947 extern initialize_file_ftype _initialize_cp_namespace;
948 
949 void
950 _initialize_cp_namespace (void)
951 {
952   struct cmd_list_element *cmd;
953 
954   cmd = add_cmd ("namespace", class_maintenance,
955 		 maintenance_cplus_namespace,
956 		 _("Deprecated placeholder for removed functionality."),
957 		 &maint_cplus_cmd_list);
958   deprecate_cmd (cmd, NULL);
959 }
960