re PR c++/67655 ([concepts] expression constraints and variadic expansions)

2018-09-26  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/67655
	* g++.dg/concepts/pr67655.C: New.

From-SVN: r264638

gcc/testsuite/ChangeLog

+2018-09-26  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/67655
+	* g++.dg/concepts/pr67655.C: New.
+
 2018-09-26  Thomas Quinot  <quinot@adacore.com>
 
 	* gnat.dg/sso13.adb: New testcase.

gcc/testsuite/g++.dg/concepts/pr67655.C

+// { dg-do compile { target c++11 } }
+// { dg-additional-options "-fconcepts" }
+
+template<class... Xs>                 
+void consume(Xs&&...) {}
+
+template<class... Xs>
+  struct A {
+    template<class... Ys>
+    requires requires(Ys... ys) {
+      consume(Xs{ys}...);
+    }
+  A(Ys&&... ys) {
+  }
+  A(int) {}
+};
+
+int main() {
+  A<int, double> a(55);
+}