[lno] Loop miscompilation

[Falk Hueffner <hueffner at informatik dot uni-tuebingen dot de>]

Hi,

this test case is extracted from gnugo. No problem with tree-ssa or
other gccs.

gcc (GCC) 3.5-tree-ssa-lno 20040314 (merged 20040221)

% gcc bla.c && ./a.out && echo --- &&  gcc -O2 bla.c && ./a.out
i = 0 j = 0 queue1[0] = 17
i = 0 j = 1 queue1[0] = 17
i = 0 j = 2 queue1[0] = 17
i = 0 j = 3 queue1[0] = 17
i = 0 j = 0 queue1[0] = 17
i = 0 j = 1 queue1[0] = 17
i = 0 j = 2 queue1[0] = 17
i = 0 j = 3 queue1[0] = 17
---
i = 0 j = 0 queue1[0] = 0
i = 0 j = 1 queue1[0] = 0
i = 0 j = 2 queue1[0] = 0
i = 0 j = 3 queue1[0] = 0


#include <stdio.h>
#include <stdlib.h>

int main(void)
{
  int *state_to;
  int *state_from;
  int *queue1;
  int *queue2;
  int *tempq;
  int next_new_state;
  int q1p;
  int q2p;
  int i, j;

  state_to = calloc(100, sizeof(int));
  state_from = calloc(100, sizeof(int));

  queue1 = malloc((100) * sizeof(int));
  queue2 = malloc((100) * sizeof(int));
  q1p = 1;
  q2p = 0;
  queue1[0] = 17;
  state_from[0] = state_to[0] = 0;
  state_from[1] = state_to[1] = 1;
  next_new_state = 2;

  while (q1p) {
    for (i = 0; i < q1p; i++) {
      for (j = 0; j < 4; j++) {
	fprintf(stderr, "i = %d j = %d queue1[%d] = %d\n", i, j, i, queue1[i]);
        int n = queue1[i];
        if (n && !state_to[n]) {
          state_to[n] = next_new_state;
          state_from[next_new_state] = n;
          next_new_state++;
          queue2[q2p++] = n;
        }
      }
    }
    tempq = queue1;
    queue1 = queue2;
    queue2 = tempq;
    q1p = q2p;
    q2p = 0;
  }

  return 0;
}


-- 
	Falk