gcc/testsuite/gcc.dg/pr29921-2.c

   1 /* With -ffast-math, the latice value for sum2 used to change from NaN to
   2    VARYING, in turn causing the lattice value of sum1 * sum2 change from
   3    NaN to 0 (since sum1 is believed to be 0 at that moment, and
   4    0 * VARYING = 0 with -ffast-math), which caused an ICE.  */
   5
   6 /* { dg-do compile } */
   7 /* { dg-options "-O2 -ffast-math" } */
   8
   9 int
  10 foo (float *array, int end)
  11 {
  12   int i;
  13   float sum1, sum2;
  14
  15   sum2 = 0;
  16   for (i = 0; i < end; i++)
  17     sum2 = sum2+array[i];
  18   sum2 = 1./sum2;
  19   sum1 = 0.;
  20   for (i = 0; i < end; i++)
  21     sum1 = sum1+array[i];
  22   sum1 = sum1 * sum2;
  23   if (-10.0 / sum1 < 5.E-5)
  24     end = 0;
  25   return end;
  26 }
  27