https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109732
--- Comment #14 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Figured out a C testcase:
```
[[gnu::noipa]]
_Bool f3(_Bool a)
{
if (a==0)
return 0;
else
return a;
}
```
Still need: `-fdisable-tree-fre1` though because fre is able to figure out that
the return value is always a. We don't need to disable ethread any more since
cfgcleanup will not remove the forwarding BB as it has a predict statement in
it.
There are actually two conditions that need to happen to get the wrong code.
First is the order of the phi and then also the order of the edges. The above
is enough to get both.
