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/* Problem originally visible on ia64.
There is a partial redundancy of "in + 1" that makes GCSE want to
transform the final while loop to
p = in + 1;
tmp = p;
...
goto start;
top:
tmp = tmp + 1;
start:
in = tmp;
if (in < p) goto top;
We miscalculate the number of loop iterations as (p - tmp) = 0
instead of (p - in) = 1, which results in overflow in the doloop
optimization. */
static const char *
test (const char *in, char *out)
{
while (1)
{
if (*in == 'a')
{
const char *p = in + 1;
while (*p == 'x')
++p;
if (*p == 'b')
return p;
while (in < p)
*out++ = *in++;
}
}
}
int main ()
{
char out[4];
test ("aab", out);
return 0;
}
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