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* [Bug c/61942] New: loop-iv.c:2272 signed integer overflow
@ 2014-07-29 6:59 zeccav at gmail dot com
2014-09-04 10:17 ` [Bug rtl-optimization/61942] " mpolacek at gcc dot gnu.org
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: zeccav at gmail dot com @ 2014-07-29 6:59 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61942
Bug ID: 61942
Summary: loop-iv.c:2272 signed integer overflow
Product: gcc
Version: 4.9.1
Status: UNCONFIRMED
Severity: minor
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: zeccav at gmail dot com
/* from pr32349.c */
// gcc -funroll-loops -O3
// ../../gcc-4.9.1/gcc/loop-iv.c:2272:24: runtime error:
// signed integer overflow: 9223372036854775807 - -9223372036854775808 cannot
be represented in type 'long int'
// offending instruction "nmax = INTVAL (mmax) - INTVAL (mmin);"
extern long *x1, *x2, *x3;
int
foo ()
{
long *p1, *p2;
long m, n, i;
p1 = x1;
p2 = x2;
n = 0;
for (i = *x3; 0 < i; i--)
{
m = (*p1++) ^ (*p2++);
m = (m & 0x55555555) + ((m >> 1) & 0x55555555);
n += m;
}
return n;
}
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug rtl-optimization/61942] loop-iv.c:2272 signed integer overflow
2014-07-29 6:59 [Bug c/61942] New: loop-iv.c:2272 signed integer overflow zeccav at gmail dot com
@ 2014-09-04 10:17 ` mpolacek at gcc dot gnu.org
2014-09-06 6:53 ` zeccav at gmail dot com
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: mpolacek at gcc dot gnu.org @ 2014-09-04 10:17 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61942
--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
I can't reproduce this one.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug rtl-optimization/61942] loop-iv.c:2272 signed integer overflow
2014-07-29 6:59 [Bug c/61942] New: loop-iv.c:2272 signed integer overflow zeccav at gmail dot com
2014-09-04 10:17 ` [Bug rtl-optimization/61942] " mpolacek at gcc dot gnu.org
@ 2014-09-06 6:53 ` zeccav at gmail dot com
2014-09-06 8:31 ` mpolacek at gcc dot gnu.org
2014-09-28 9:09 ` trippels at gcc dot gnu.org
3 siblings, 0 replies; 5+ messages in thread
From: zeccav at gmail dot com @ 2014-09-06 6:53 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61942
--- Comment #2 from Vittorio Zecca <zeccav at gmail dot com> ---
This is what I get on x86-64 with a sanitized version of gcc:
~/local/gcc-4.9.1-sanitized/bin/gcc -S gccerr12.c -funroll-loops -O3
../../gcc-4.9.1/gcc/loop-iv.c:2272:24: runtime error: signed integer overflow:
9223372036854775807 - -9223372036854775808 cannot be represented in type 'long
int'
Please note the -funroll-loops -O3 options.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug rtl-optimization/61942] loop-iv.c:2272 signed integer overflow
2014-07-29 6:59 [Bug c/61942] New: loop-iv.c:2272 signed integer overflow zeccav at gmail dot com
2014-09-04 10:17 ` [Bug rtl-optimization/61942] " mpolacek at gcc dot gnu.org
2014-09-06 6:53 ` zeccav at gmail dot com
@ 2014-09-06 8:31 ` mpolacek at gcc dot gnu.org
2014-09-28 9:09 ` trippels at gcc dot gnu.org
3 siblings, 0 replies; 5+ messages in thread
From: mpolacek at gcc dot gnu.org @ 2014-09-06 8:31 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61942
--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
I tried trunk again and still nothing, so maybe only 4.9 is affected.
But both 4.9/trunk contain the "nmax = INTVAL (mmax) - INTVAL (mmin);" line...
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug rtl-optimization/61942] loop-iv.c:2272 signed integer overflow
2014-07-29 6:59 [Bug c/61942] New: loop-iv.c:2272 signed integer overflow zeccav at gmail dot com
` (2 preceding siblings ...)
2014-09-06 8:31 ` mpolacek at gcc dot gnu.org
@ 2014-09-28 9:09 ` trippels at gcc dot gnu.org
3 siblings, 0 replies; 5+ messages in thread
From: trippels at gcc dot gnu.org @ 2014-09-28 9:09 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61942
Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
CC| |trippels at gcc dot gnu.org
Resolution|--- |DUPLICATE
--- Comment #5 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
dup.
*** This bug has been marked as a duplicate of bug 61657 ***
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2014-09-28 9:09 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-07-29 6:59 [Bug c/61942] New: loop-iv.c:2272 signed integer overflow zeccav at gmail dot com
2014-09-04 10:17 ` [Bug rtl-optimization/61942] " mpolacek at gcc dot gnu.org
2014-09-06 6:53 ` zeccav at gmail dot com
2014-09-06 8:31 ` mpolacek at gcc dot gnu.org
2014-09-28 9:09 ` trippels at gcc dot gnu.org
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