1 files changed, 60 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/duff-2.c b/gcc/testsuite/gcc.dg/duff-2.c
new file mode 100644
index 000000000..8b8923eb9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/duff-2.c
@@ -0,0 +1,60 @@
+/* Duff's device is legal C; test to make sure the compiler
+   doesn't complain about it.
+
+   Jason Thorpe <thorpej@wasabisystems.com>
+   Derived from the BSD Telnet Kerberos 4 checksum routine.
+   See also PR 5230.  */
+
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+extern void abort (void);
+extern void exit (int);
+
+#if __INT_MAX__ >= 2147483647
+/* At least 32-bit integers. */
+typedef int type32;
+#else
+typedef long type32;
+#endif
+
+type32
+cksum (const unsigned char *src, unsigned long size)
+{
+  type32 ck = 0;
+
+  switch (size & 3)
+    {
+    while (size > 0)
+      {
+    case 0:
+	ck ^= (type32)*src++ << 24;
+	--size;
+    case 3:
+	ck ^= (type32)*src++ << 16;
+	--size;
+    case 2:
+	ck ^= (type32)*src++ << 8;
+	--size;
+    case 1:
+	ck ^= (type32)*src++;
+	--size;
+      }
+    }
+
+  return ck;
+}
+
+const char testpat[] = "The quick brown fox jumped over the lazy dog.";
+
+int
+main()
+{
+  type32 ck;
+
+  ck = cksum ((const unsigned char *) testpat, sizeof (testpat));
+  if (ck != 925902908)
+    abort ();
+
+  exit (0);
+}