--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/c-c++-common/Wswitch-unreachable-3.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+
+extern void f (int *);
+
+void
+g (int i)
+{
+  switch (i)
+    {
+      int a[3];
+      __builtin_memset (a, 0, sizeof a); /* { dg-warning "statement will never be executed" } */
+
+    default:
+      f (a);
+    }
+
+  switch (i)
+    {
+      int a[3];
+      int b[3];
+      int c[3];
+      b[1] = 60; /* { dg-warning "statement will never be executed" } */
+
+    default:
+      f (a);
+      f (b);
+      f (c);
+    }
+}