--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/concepts/abbrev2.C	Thu Oct 25 07:37:49 2018 +0900
@@ -0,0 +1,17 @@
+// PR c++/66197
+// { dg-do run { target c++14 } }
+// { dg-additional-options "-fconcepts" }
+
+extern "C" void abort();
+
+auto add_1(auto a, auto b) { return a + b; }
+auto add_2 = [](auto a, auto b) { return a + b; };
+
+int main()
+{
+  if (add_1(3.5, 4) != 7.5
+      || add_1(3, 4.5) != 7.5
+      || add_2(3.5, 4) != 7.5
+      || add_2(3, 4.5) != 7.5)
+    abort();
+}