--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/cpp0x/explicit4.C	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,17 @@
+// Negative explicit conv test.
+// { dg-do compile { target c++11 } }
+
+struct A {
+  A(const A&, int = 0);		// { dg-message "note" }
+};
+struct B
+{
+  explicit operator A();
+};
+
+int main()
+{
+  B b;
+  (A(b));			// OK
+  (A(b,1));			// { dg-error "no match" }
+}