http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56488
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |wrong-code
CC| |rguenth at gcc dot gnu.org
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> 2013-03-01
12:20:21 UTC ---
The fixing rev. doesn't make much sense ;) The issue must be still latent.
> But e = e + 5 is avaluated as
> e = (short) ((int) e + 5)
not true before VRP2:
short int e.2;
short int e.4;
...
<bb 3>:
# e.2_4 = PHI <e.4_18(3), 0(2)>
f = b;
D.1777_45 = e.2_4 + 5;
e.4_18 = D.1777_45;
e = e.4_18;
if (e.4_18 != 1)
goto <bb 3>;
else
goto <bb 4>;
which turns it into an endless loop. The FE shortened to
e = (short int) ((short unsigned int) e + 5);
but IVOPTs makes it short. There was a related bugfix by Zdenek for 4.8.
