--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/wtr-union-init-3.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,64 @@
+/* Test for -Wtraditional warnings on union initialization.
+   Note, gcc should omit these warnings in system header files.
+   By Kaveh R. Ghazi <ghazi@caip.rutgers.edu> 9/11/2000.  */
+/* { dg-do compile } */
+/* { dg-options "-Wtraditional" } */
+
+struct bar
+{
+  int i;
+  long j;
+};
+
+union foo
+{
+  struct bar b;
+  int i;
+  long l;
+};
+
+union foo2
+{
+  int i;
+  long l;
+};
+
+struct baz
+{
+  int a;
+  double b;
+  union foo c;
+};
+
+struct baz2
+{
+  int a;
+  double b;
+  union foo2 c;
+};
+
+void
+testfunc ()
+{
+  /* Note we only warn for nonzero initializers.  Xfail on substructures. */
+  static union foo f1 = {{0,0}}; /* { dg-bogus "traditional C rejects initialization of unions" "initialization of unions" { xfail *-*-* } } */
+  static union foo f2 = {{1,1}}; /* { dg-warning "traditional C rejects initialization of unions" "initialization of unions" } */
+
+  static struct baz f3 = { 1, 2, {{0,0}} }; /* { dg-bogus "traditional C rejects initialization of unions" "initialization of unions" { xfail *-*-* } } */
+  static struct baz f4 = { 1, 2, {{1,1}} }; /* { dg-warning "traditional C rejects initialization of unions" "initialization of unions" } */
+
+  static struct baz2 f5 = { 1, 2, {0} };
+  static struct baz2 f6 = { 1, 2, {1} }; /* { dg-warning "traditional C rejects initialization of unions" "initialization of unions" } */
+
+# 54 "sys-header.h" 3
+/* We are in system headers now, no -Wtraditional warnings should issue.  */
+
+  static union foo b1 = {{0,0}};
+  static union foo b2 = {{1,1}};
+
+  static struct baz b3 = { 1, 2, {{0,0}} };
+  static struct baz b4 = { 1, 2, {{1,1}} };
+
+  static struct baz2 b5 = { 1, 2, {0} };
+  static struct baz2 b6 = { 1, 2, {1} };
+}