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-rw-r--r--gcc/testsuite/gcc.dg/duff-4.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/duff-4.c b/gcc/testsuite/gcc.dg/duff-4.c
new file mode 100644
index 000000000..7032285af
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/duff-4.c
@@ -0,0 +1,60 @@
+/* Duff's device is legal C; test to make sure the compiler
+ doesn't complain about it.
+
+ Roger Sayle <roger@eyesopen.com>
+ Derived from duff-2.c. */
+
+/* { 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)
+ {
+ do
+ {
+ 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;
+ }
+ while (size > 0);
+ }
+
+ 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);
+}