--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/c-c++-common/Wunused-var-3.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+/* { dg-options "-Wunused" } */
+
+void
+f1 (void)
+{
+  _Complex int a;	/* { dg-warning "set but not used" } */
+  _Complex double b;	/* { dg-warning "set but not used" } */
+  __real__ a = 1;
+  __imag__ a = 2;
+  __real__ b = 3.0;
+  __imag__ b = 4.0;
+}
+
+int
+f2 (void)
+{
+  _Complex int a;
+  _Complex double b;
+  __real__ a = 1;
+  __imag__ a = 2;
+  __real__ b = 3.0;
+  __imag__ b = 4.0;
+  return __real__ a + __imag__ b;
+}
+
+_Complex double
+f3 (void)
+{
+  _Complex int a;
+  _Complex double b;
+  __real__ a = 1;
+  __imag__ a = 2;
+  __real__ b = 3.0;
+  __imag__ b = 4.0;
+  return a + b;
+}