re PR c++/19253 (bad error message / ICE for invalid template parameter)

	PR c++/19253
	* parser.c (cp_parser_diagnose_invalid_type_name): Commit to
	tentative parses.

	PR c++/19253
	* g++.dg/template/crash33.C: New test.

From-SVN: r94403

gcc/cp/ChangeLog

 2005-01-28  Mark Mitchell  <mark@codesourcery.com>
 
+	PR c++/19253
+	* parser.c (cp_parser_diagnose_invalid_type_name): Commit to
+	tentative parses.
+
 	PR c++/19667
 	* pt.c (redeclare_class_template): Robustify.
 

gcc/cp/parser.c

@@ -1961,7 +1961,10 @@ cp_parser_non_integral_constant_expression (cp_parser  *parser,
 }
 
 /* Emit a diagnostic for an invalid type name.  SCOPE is the
-   qualifying scope (or NULL, if none) for ID.  */
+   qualifying scope (or NULL, if none) for ID.  This function commits
+   to the current active tentative parse, if any.  (Otherwise, the
+   problematic construct might be encountered again later, resulting
+   in duplicate error messages.)  */
 
 static void
 cp_parser_diagnose_invalid_type_name (cp_parser *parser, tree scope, tree id)
@@ -2033,6 +2036,7 @@ cp_parser_diagnose_invalid_type_name (cp_parser *parser, tree scope, tree id)
       else
 	gcc_unreachable ();
     }
+  cp_parser_commit_to_tentative_parse (parser);
 }
 
 /* Check for a common situation where a type-name should be present,

gcc/testsuite/ChangeLog

 2005-01-28  Mark Mitchell  <mark@codesourcery.com>
 
+	PR c++/19253
+	* g++.dg/template/crash33.C: New test.
+
 	PR c++/19667
 	* g++.dg/template/crash32.C: New test.
 

gcc/testsuite/g++.dg/template/crash33.C

+// PR c++/19253
+
+namespace N {}
+
+template<typename> struct A
+{
+  A<typename N::X<int> > a; // { dg-error "" }
+};