gcc/testsuite/gcc.dg/fold-sub.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-ffinite-math-only -fdump-tree-gimple" } */
   3
   4 float f(float x)
   5 {
   6   return x - x;
   7 }
   8
   9 /* Substraction should be turned into 0.  */
  10
  11 /* { dg-final { scan-tree-dump-not " - " "gimple" } } */