--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/Wcxx-compat-5.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,45 @@
+/* { dg-do compile } */
+/* { dg-options "-Wc++-compat" } */
+enum E1 { A, B, C };
+enum E2 { D, E, F };
+
+int f1() { return A; }
+
+struct s { enum E1 e1 : 3; enum E2 e2 : 4; };
+
+enum E1
+f2 (int i, struct s sv, struct s *pv)
+{
+  int a;
+  enum E1 e1 = B;
+  enum E2 e2 = E;
+  switch (i)
+    {
+    case 0:
+      return A;
+    case 1:
+      return D;			/* { dg-warning "invalid in C\[+\]\[+\]" } */
+    case 2:
+      return 0;			/* { dg-warning "invalid in C\[+\]\[+\]" } */
+    case 3:
+      return (enum E1) 1;
+    case 4:
+      return (enum E2) 2;	/* { dg-warning "invalid in C\[+\]\[+\]" } */
+    case 5:
+      return e1;
+    case 6:
+      return e2;		/* { dg-warning "invalid in C\[+\]\[+\]" } */
+    case 7:
+      return pv->e1;
+    case 8:
+      return sv.e1;
+    case 9:
+      return pv->e2;		/* { dg-warning "invalid in C\[+\]\[+\]" } */
+    case 10:
+      return sv.e2;		/* { dg-warning "invalid in C\[+\]\[+\]" } */
+    case 11:
+      return 1, A;
+    default:
+      return C;
+    }
+}