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/* 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);
}
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