Comment 5 for bug 1584602

$ cat notify.i
_Bool a;
fn1(unsigned int p1) {
  unsigned int b = a ? p1 : 0;
  if (p1 || b)
    fn2(0, p1, b);
}
$ gcc -c -O1 -fno-if-conversion notify.i
$ gcc -c -O1 notify.i
notify.i: In function 'fn1':
notify.i:6:1: internal compiler error: in fixup_reorder_chain, at cfgrtl.c:3336
 }
 ^
Please submit a full bug report,
with preprocessed source if appropriate.

still seen in 4.8.5 (16.04), doesn't show in 4.9 (and gcc-snapshot in trusty)