gcc/testsuite/gcc.dg/pr18628.c

   1 /* { dg-do link } */
   2 /* { dg-options "-O2" } */
   3
   4 /* PR middle-end/18628 exposed a problem in which cse folded a load
   5    from a jump table into the label that was the target of the branch.
   6    Unfortunately, the indirect jump was moved to a different basic
   7    block, and the LABEL_REF copied to the register wasn't enough to
   8    keep the cfg from optimizing the otherwise-unused label away.  So
   9    we ended up with a dangling reference to the label.  */
  10
  11 int i;
  12
  13 int main()
  14 {
  15   for (;;)
  16   {
  17     switch (i)
  18     {
  19       case 0:
  20       case 1:
  21         return 1;
  22
  23       case 2:
  24       case 3:
  25         return 0;
  26
  27       case 5:
  28         --i;
  29     }
  30   }
  31 }