re PR c++/18652 (ICE on invalid redeclaration)

	PR c++/18652
	* name-lookup.c (pushtag): Change return type to tree.
	* cp-tree.h (pushtag): Adjust declaration.
	* decl.c (xref_tag, start_enum): Use return value of pushtag.
	* pt.c (push_template_decl_real): Return immediately if
	pushdecl_namespace_level returns error_mark_node.

	* g++.dg/lookup/crash6.C: New test.

From-SVN: r91470

gcc/cp/ChangeLog

+2004-11-29  Kriang Lerdsuwanakij  <lerdsuwa@users.sourceforge.net>
+
+	PR c++/18652
+	* name-lookup.c (pushtag): Change return type to tree.
+	* cp-tree.h (pushtag): Adjust declaration.
+	* decl.c (xref_tag, start_enum): Use return value of pushtag.
+	* pt.c (push_template_decl_real): Return immediately if
+	pushdecl_namespace_level returns error_mark_node.
+
 2004-11-27  Kazu Hirata  <kazu@cs.umass.edu>
 
 	* pt.c: Fix a comment typo.

gcc/cp/cp-tree.h

@@ -3707,7 +3707,7 @@ extern void delete_block			(tree);
 extern void add_block_current_level		(tree);
 extern void push_switch				(tree);
 extern void pop_switch				(void);
-extern void pushtag				(tree, tree, int);
+extern tree pushtag				(tree, tree, int);
 extern tree make_anon_name			(void);
 extern int decls_match				(tree, tree);
 extern tree duplicate_decls			(tree, tree);

gcc/cp/decl.c

@@ -9284,7 +9284,7 @@ xref_tag (enum tag_types tag_code, tree name,
 	  t = make_aggr_type (code);
 	  TYPE_CONTEXT (t) = context;
 	  /* pushtag only cares whether SCOPE is zero or not.  */
-	  pushtag (name, t, scope != ts_current);
+	  t = pushtag (name, t, scope != ts_current);
 	}
     }
   else
@@ -9539,7 +9539,7 @@ start_enum (tree name)
 	name = make_anon_name ();
 
       enumtype = make_node (ENUMERAL_TYPE);
-      pushtag (name, enumtype, 0);
+      enumtype = pushtag (name, enumtype, 0);
     }
 
   return enumtype;

gcc/cp/name-lookup.c

@@ -4566,9 +4566,10 @@ maybe_process_template_type_declaration (tree type, int globalize,
 /* Push a tag name NAME for struct/class/union/enum type TYPE.
    Normally put it into the inner-most non-sk_cleanup scope,
    but if GLOBALIZE is true, put it in the inner-most non-class scope.
-   The latter is needed for implicit declarations.  */
+   The latter is needed for implicit declarations.
+   Returns TYPE upon success and ERROR_MARK_NODE otherwise.  */
 
-void
+tree
 pushtag (tree name, tree type, int globalize)
 {
   struct cp_binding_level *b;
@@ -4633,6 +4634,8 @@ pushtag (tree name, tree type, int globalize)
 
 	  d = maybe_process_template_type_declaration (type,
 						       globalize, b);
+	  if (d == error_mark_node)
+	    return error_mark_node;
 
 	  if (b->kind == sk_class)
 	    {
@@ -4695,7 +4698,7 @@ pushtag (tree name, tree type, int globalize)
       tree d = build_decl (TYPE_DECL, NULL_TREE, type);
       TYPE_STUB_DECL (type) = pushdecl_with_scope (d, b);
     }
-  timevar_pop (TV_NAME_LOOKUP);
+  POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, type);
 }
 
 /* Subroutines for reverting temporarily to top-level for instantiation

gcc/cp/pt.c

@@ -3145,7 +3145,11 @@ push_template_decl_real (tree decl, int is_friend)
      parameters of the class.  */
   if (new_template_p && !ctx 
       && !(is_friend && template_class_depth (current_class_type) > 0))
+    {
       tmpl = pushdecl_namespace_level (tmpl);
+      if (tmpl == error_mark_node)
+	return error_mark_node;
+    }
 
   if (primary)
     {

gcc/testsuite/ChangeLog

+2004-11-29  Kriang Lerdsuwanakij  <lerdsuwa@users.sourceforge.net>
+
+	PR c++/18652
+	* g++.dg/lookup/crash6.C: New test.
+
 2004-11-29  Hans-Peter Nilsson  <hp@bitrange.com>
 
 	PR middle-end/18164

gcc/testsuite/g++.dg/lookup/crash6.C

+// { dg-do compile }
+
+// Origin: Volker Reichelt <reichelt@gcc.gnu.org>
+
+// PR c++/18652: ICE redeclaring variable as template.
+
+int A;			// { dg-error "previous declaration" }
+template<int> struct A; // { dg-error "different kind of symbol" }