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-rw-r--r--gcc-4.9/gcc/testsuite/gcc.dg/duff-1.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/gcc-4.9/gcc/testsuite/gcc.dg/duff-1.c b/gcc-4.9/gcc/testsuite/gcc.dg/duff-1.c
new file mode 100644
index 000000000..b718f6c05
--- /dev/null
+++ b/gcc-4.9/gcc/testsuite/gcc.dg/duff-1.c
@@ -0,0 +1,50 @@
+/* Duff's device is legal C; test to make sure the compiler
+ doesn't complain about it.
+
+ Jason Thorpe <thorpej@wasabisystems.com>
+ Derived from PR 3846. */
+
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+extern void abort (void);
+extern void exit (int);
+
+typedef __SIZE_TYPE__ size_t;
+extern int memcmp (const void *, const void *, size_t);
+
+void
+duffcpy (char *dst, const char *src, unsigned long size)
+{
+ switch (size & 3)
+ {
+ for (;;)
+ {
+ *dst++ = *src++;
+ case 3:
+ *dst++ = *src++;
+ case 2:
+ *dst++ = *src++;
+ case 1:
+ *dst++ = *src++;
+ case 0:
+ if (size <= 3)
+ break;
+ size -= 4;
+ }
+ }
+}
+
+const char testpat[] = "The quick brown fox jumped over the lazy dog.";
+
+int
+main()
+{
+ char buf[64];
+
+ duffcpy (buf, testpat, sizeof (testpat));
+ if (memcmp (buf, testpat, sizeof (testpat)) != 0)
+ abort ();
+
+ exit (0);
+}