commit d31ae27e292c03ab16feb0ac714ec62b12165444
Author: Jason Merrill <jason@redhat.com>
Date: Mon Mar 11 16:35:02 2013 -0400
PR c++/56039
* tree.c (strip_typedefs_expr): Complain about lambda, don't abort.
@@ -1421,7 +1421,8 @@ strip_typedefs_expr (tree t)
}
case LAMBDA_EXPR:
- gcc_unreachable ();
+ error ("lambda-expression in a constant expression");
+ return error_mark_node;
default:
break;
new file mode 100644
@@ -0,0 +1,55 @@
+// PR c++/56039
+// { dg-do compile { target c++11 } }
+
+template <bool> struct BoolSink { typedef void type; };
+
+template <typename T, typename U>
+struct AddRvalueReferenceImpl { typedef T type; };
+
+template <typename T>
+struct AddRvalueReferenceImpl<T, typename BoolSink<false &&
+ [] {
+ extern T &&tref;
+ }>::type> { // { dg-error "lambda" }
+ typedef T &&type;
+};
+
+template <typename T>
+struct AddRvalueReference : AddRvalueReferenceImpl<T, void> { };
+
+namespace ImplHelpers {
+ template <typename T>
+ typename AddRvalueReference<T>::type create(void) { }
+}
+
+template <typename T, typename U, typename ...Args>
+struct IsConstructibleImpl { enum { value = 0 }; };
+
+template <typename T, typename ...Args>
+struct IsConstructibleImpl<T, typename BoolSink<false &&
+ [] {
+ T t( ::ImplHelpers::create<Args>() ...);
+ }>::type, Args ...> { // { dg-error "lambda" }
+ enum { value = 1 };
+};
+
+template <typename T, typename ...Args>
+struct IsConstructible : IsConstructibleImpl<T, void, Args ...> { };
+
+struct DestroyMe {
+ ~DestroyMe() = delete;
+};
+
+static_assert(+IsConstructible<int>::value, "error");
+static_assert(!IsConstructible<void>::value, "error");
+static_assert(+IsConstructible<int [1]>::value, "error");
+static_assert(!IsConstructible<DestroyMe>::value, "error");
+static_assert(!IsConstructible<int *, char *>::value, "error");
+
+static_assert(+IsConstructible<int &&, int>::value, "error");
+static_assert(!IsConstructible<int &&, int &>::value, "error");
+static_assert(+IsConstructible<int &&, int &&>::value, "error");
+
+// { dg-prune-output "expected" }
+// { dg-prune-output "does not name a class" }
+// { dg-prune-output "static assertion" }