/* 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;
}
