------- Comment #1 from jakub at gcc dot gnu dot org 2009-12-01 08:19 -------
Simplified testcase without the undefined signed underflow:
void
foo (int x)
{
struct S { int s; } d = { 1 };
unsigned int e = 1;
if (x)
e = x && d.s;
else
for (e = 0; e <= 3; e--)
;
e++;
}
The problem starts in *.cddce1, before that we have:
# e_2 = PHI <e_9(6), e_1(8)>
# DEBUG e => e_2
# DEBUG e => e_2 + 1
but after that only:
<bb 6>:
# DEBUG e => e_1
# DEBUG e => e_1 + 1
where e_1 is defined only in one of the predecessors of bb 6.
--
jakub at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2009-12-01 08:19:33
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42234
