re PR c++/82570 (Lambda fails to compile because it doesn't meet constexpr requirements)

2017-10-17  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/82570
	* g++.dg/cpp1z/constexpr-lambda18.C: New.

From-SVN: r253806

gcc/testsuite/ChangeLog

+2017-10-17  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/82570
+	* g++.dg/cpp1z/constexpr-lambda18.C: New.
+
 2017-10-17  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/82549

gcc/testsuite/g++.dg/cpp1z/constexpr-lambda18.C

+// PR c++/82570
+// { dg-options "-std=c++17" }
+
+template< typename Body >
+inline void iterate(Body body)
+{
+	body(10);
+}
+
+template< typename Pred >
+inline void foo(Pred pred)
+{
+	iterate([&](int param)
+	{
+		if (pred(param))
+		{
+			unsigned char buf[4];
+			buf[0] = 0;
+			buf[1] = 1;
+			buf[2] = 2;
+			buf[3] = 3;
+		}
+	});
+}
+
+int main()
+{
+	foo([](int x) { return x > 0; });
+	return 0;
+}