call.c (type_decays_to): Check MAYBE_CLASS_TYPE_P instead of CLASS_TYPE_P.

	* call.c (type_decays_to): Check MAYBE_CLASS_TYPE_P instead of
	CLASS_TYPE_P.
	* parser.c (cp_parser_lambda_expression): Complain about lambda in
	unevaluated context.
	* pt.c (iterative_hash_template_arg): Don't crash on lambda.

From-SVN: r158277

gcc/cp/ChangeLog

+2010-04-13  Jason Merrill  <jason@redhat.com>
+
+	* call.c (type_decays_to): Check MAYBE_CLASS_TYPE_P instead of
+	CLASS_TYPE_P.
+	* parser.c (cp_parser_lambda_expression): Complain about lambda in
+	unevaluated context.
+	* pt.c (iterative_hash_template_arg): Don't crash on lambda.
+
 2010-04-12  Jason Merrill  <jason@redhat.com>
 
 	PR c++/43641

gcc/cp/call.c

@@ -2263,7 +2263,7 @@ type_decays_to (tree type)
     return build_pointer_type (TREE_TYPE (type));
   if (TREE_CODE (type) == FUNCTION_TYPE)
     return build_pointer_type (type);
-  if (!CLASS_TYPE_P (type))
+  if (!MAYBE_CLASS_TYPE_P (type))
     type = cv_unqualified (type);
   return type;
 }

gcc/cp/parser.c

@@ -7081,6 +7081,10 @@ cp_parser_lambda_expression (cp_parser* parser)
   LAMBDA_EXPR_LOCATION (lambda_expr)
     = cp_lexer_peek_token (parser->lexer)->location;
 
+  if (cp_unevaluated_operand)
+    error_at (LAMBDA_EXPR_LOCATION (lambda_expr),
+	      "lambda-expression in unevaluated context");
+
   /* We may be in the middle of deferred access check.  Disable
      it now.  */
   push_deferring_access_checks (dk_no_deferred);

gcc/cp/pt.c

@@ -1563,6 +1563,12 @@ iterative_hash_template_arg (tree arg, hashval_t val)
       val = iterative_hash_template_arg (TREE_TYPE (arg), val);
       return iterative_hash_template_arg (TYPE_DOMAIN (arg), val);
 
+    case LAMBDA_EXPR:
+      /* A lambda can't appear in a template arg, but don't crash on
+	 erroneous input.  */
+      gcc_assert (errorcount > 0);
+      return val;
+
     default:
       switch (tclass)
 	{

gcc/testsuite/ChangeLog

+2010-04-13  Jason Merrill  <jason@redhat.com>
+
+	* g++.dg/cpp0x/lambda/lambda-deduce2.C: Remove.
+	* g++.dg/cpp0x/lambda/lambda-uneval.C: New.
+
 2010-04-13  Manuel López-Ibáñez  <manu@gcc.gnu.org>
 
 	* gcc.dg/cpp/cpp.exp: Test also c-c++-common/cpp.

gcc/testsuite/g++.dg/cpp0x/lambda/lambda-deduce2.C

-// Test that cv-quals are dropped from non-class return type
-// { dg-options "-std=c++0x" }
-
-template <class T, class U>
-struct assert_same_type;
-template <class T>
-struct assert_same_type<T,T> { };
-
-struct A
-{
-  int i;
-};
-
-extern const int i;
-assert_same_type <decltype ([]{ return i; }()), int> x;

gcc/testsuite/g++.dg/cpp0x/lambda/lambda-uneval.C

+// 5.1.2/2: A lambda-expression shall not appear in an unevaluated operand.
+// { dg-options "-std=c++0x" }
+
+template <class T>
+struct A { };
+A<decltype([]{ return 1; }())> a; // { dg-error "lambda.*unevaluated context" }
+