re PR c++/21687 (ICE in GC with local class inside a template function)

	PR c++/21687
	* parser.c (cp_parser_class_specifier): Push/pop GC contexts
	around functions in local classes.

	PR c++/21687
	* g++.dg/other/gc3.C: New test.

From-SVN: r103791

gcc/cp/ChangeLog

+2005-09-02  Mark Mitchell  <mark@codesourcery.com>
+
+	PR c++/21687
+	* parser.c (cp_parser_class_specifier): Push/pop GC contexts
+	around functions in local classes.
+
 2005-08-31  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	PR obj-c++/23640

gcc/cp/parser.c

@@ -12673,7 +12673,10 @@ cp_parser_class_specifier (cp_parser* parser)
       tree fn;
       tree class_type = NULL_TREE;
       tree pushed_scope = NULL_TREE;
-
+      /* True if we have called ggc_push_context, and therefore need
+	 to make a matching call to ggc_pop_context.  */
+      bool need_ggc_pop_context;
+ 
       /* In a first pass, parse default arguments to the functions.
 	 Then, in a second pass, parse the bodies of the functions.
 	 This two-phased approach handles cases like:
@@ -12709,6 +12712,7 @@ cp_parser_class_specifier (cp_parser* parser)
 	}
       if (pushed_scope)
 	pop_scope (pushed_scope);
+      need_ggc_pop_context = false;
       /* Now parse the body of the functions.  */
       for (TREE_VALUE (parser->unparsed_functions_queues)
 	     = nreverse (TREE_VALUE (parser->unparsed_functions_queues));
@@ -12718,14 +12722,21 @@ cp_parser_class_specifier (cp_parser* parser)
 	{
 	  /* Figure out which function we need to process.  */
 	  fn = TREE_VALUE (queue_entry);
-
-	  /* A hack to prevent garbage collection.  */
-	  function_depth++;
-
+	  /* We call ggc_collect after processing a function body in
+	     order to clean up garbage generated.  If we're processing
+	     a local class, however, then we must not clean up stuff
+	     from the function containing the class, so we have to
+	     push a new garbage-collection context.  */
+	  if (function_depth && !need_ggc_pop_context)
+	    {
+	      need_ggc_pop_context = true;
+	      ggc_push_context ();
+	    }
 	  /* Parse the function.  */
 	  cp_parser_late_parsing_for_member (parser, fn);
-	  function_depth--;
 	}
+      if (need_ggc_pop_context)
+	ggc_pop_context ();
     }
 
   /* Put back any saved access checks.  */

gcc/testsuite/ChangeLog

+2005-09-02  Mark Mitchell  <mark@codesourcery.com>
+
+	PR c++/21687
+	* g++.dg/other/gc3.C: New test.
+
 2005-08-31  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	* gcc.dg/20030711-1.c: Include stddef.h and stdio.h.

gcc/testsuite/g++.dg/other/gc3.C

+// PR c++/21687
+// { dg-options "--param ggc-min-expand=0 --param ggc-min-heapsize=0" }
+
+template <class Union>
+void perform_test_trivial() {
+  struct check_union {  void perform_test_trivial() {} };
+}
+