https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104196
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Here is one which shows the issue just in case fold gets in the way:
int a = 6;
int main() {
for (;;)
{
int c = 111;
if (a < 0)
c = -__INT_MAX__ - a;
int b = a;
if (a >= 0 || c > 0)
b = 0;
if (b != 4096 - __INT_MAX__) {
if (a < 6)
__builtin_abort ();
return 0;
}
}
}
The main point is the undefined behavior of -__INT_MAX__ - a when a is not less
than 0 which is not true here as a is always 6.
Also for some reason using the C++ front-end also works around the issue ...
(but I don't see how though).
