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* [Bug tree-optimization/101001] New: wrong code at -O3 on x86_64-linux-gnu
@ 2021-06-09 19:37 qrzhang at gatech dot edu
2021-06-10 6:50 ` [Bug tree-optimization/101001] [9/10/11/12 Regression] " rguenth at gcc dot gnu.org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: qrzhang at gatech dot edu @ 2021-06-09 19:37 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101001
Bug ID: 101001
Summary: wrong code at -O3 on x86_64-linux-gnu
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: qrzhang at gatech dot edu
Target Milestone: ---
It affects gcc-8 to the trunk. Gcc-7 works fine.
$ gcc-trunk -v
gcc version 12.0.0 20210609 (experimental) [master revision
174e75a2107:3b61ba37fe1:5bfcfe3087eb05b76395c9efbfc1abbf3f9e1a03] (GCC)
$ gcc-trunk abc.c ; ./a.out
0
$ gcc-trunk -O3 abc.c ; ./a.out
Segmentation fault
$ cat abc.c
int a;
volatile char b;
int main() {
char c;
int d, f = 5;
short e;
e = 0;
for (; e != -15; e--) {
d = 0;
for (; d > -16; d = d - 4) {
f || b;
c = 0;
for (; c != 2; c = c - 3)
f = 0;
}
}
printf("%X\n", a);
}
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/101001] [9/10/11/12 Regression] wrong code at -O3 on x86_64-linux-gnu
2021-06-09 19:37 [Bug tree-optimization/101001] New: wrong code at -O3 on x86_64-linux-gnu qrzhang at gatech dot edu
@ 2021-06-10 6:50 ` rguenth at gcc dot gnu.org
2021-06-10 7:26 ` rguenth at gcc dot gnu.org
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu.org @ 2021-06-10 6:50 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101001
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|wrong code at -O3 on |[9/10/11/12 Regression]
|x86_64-linux-gnu |wrong code at -O3 on
| |x86_64-linux-gnu
Target Milestone|--- |9.5
Version|unknown |12.0
Keywords| |needs-bisection, wrong-code
Known to work| |7.5.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/101001] [9/10/11/12 Regression] wrong code at -O3 on x86_64-linux-gnu
2021-06-09 19:37 [Bug tree-optimization/101001] New: wrong code at -O3 on x86_64-linux-gnu qrzhang at gatech dot edu
2021-06-10 6:50 ` [Bug tree-optimization/101001] [9/10/11/12 Regression] " rguenth at gcc dot gnu.org
@ 2021-06-10 7:26 ` rguenth at gcc dot gnu.org
2021-06-14 9:43 ` jakub at gcc dot gnu.org
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu.org @ 2021-06-10 7:26 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101001
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed| |2021-06-10
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
Depends on| |100934
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
We end up with
<bb 2> [count: 0]:
b.1_18 ={v} b;
b.1_5 ={v} b;
...
b.1_1 ={v} b;
__builtin_unreachable ();
}
sounds related to PR100934, "fixed" with -fdisable-tree-cunroll.
Loop 1 iterates at most 15 times.
Loop 1 likely iterates at most 15 times.
-fdisable-tree-thread2 "fixes" it as well. Likely a duplicate.
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100934
[Bug 100934] [9/10/11/12 Regression] wrong code at -O3 during unrolling since
r9-6299
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/101001] [9/10/11/12 Regression] wrong code at -O3 on x86_64-linux-gnu
2021-06-09 19:37 [Bug tree-optimization/101001] New: wrong code at -O3 on x86_64-linux-gnu qrzhang at gatech dot edu
2021-06-10 6:50 ` [Bug tree-optimization/101001] [9/10/11/12 Regression] " rguenth at gcc dot gnu.org
2021-06-10 7:26 ` rguenth at gcc dot gnu.org
@ 2021-06-14 9:43 ` jakub at gcc dot gnu.org
2021-10-13 10:10 ` rguenth at gcc dot gnu.org
2021-11-09 7:57 ` pinskia at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: jakub at gcc dot gnu.org @ 2021-06-14 9:43 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101001
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords|needs-bisection |
CC| |jakub at gcc dot gnu.org
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started with r9-6299-gd7a700e0a701e5164b8c547f76a2d91f657eee97
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/101001] [9/10/11/12 Regression] wrong code at -O3 on x86_64-linux-gnu
2021-06-09 19:37 [Bug tree-optimization/101001] New: wrong code at -O3 on x86_64-linux-gnu qrzhang at gatech dot edu
` (2 preceding siblings ...)
2021-06-14 9:43 ` jakub at gcc dot gnu.org
@ 2021-10-13 10:10 ` rguenth at gcc dot gnu.org
2021-11-09 7:57 ` pinskia at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu.org @ 2021-10-13 10:10 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101001
Bug 101001 depends on bug 100934, which changed state.
Bug 100934 Summary: [9 Regression] wrong code at -O3 during unrolling since r9-6299
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100934
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution|--- |FIXED
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/101001] [9/10/11/12 Regression] wrong code at -O3 on x86_64-linux-gnu
2021-06-09 19:37 [Bug tree-optimization/101001] New: wrong code at -O3 on x86_64-linux-gnu qrzhang at gatech dot edu
` (3 preceding siblings ...)
2021-10-13 10:10 ` rguenth at gcc dot gnu.org
@ 2021-11-09 7:57 ` pinskia at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-11-09 7:57 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101001
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to work| |11.2.0
Resolution|--- |DUPLICATE
Status|NEW |RESOLVED
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Dup of bug 100934. Fixed in GCC 9.5.0, 10.4.0, 11.2.0 and 12+.
*** This bug has been marked as a duplicate of bug 100934 ***
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-11-09 7:57 UTC | newest]
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2021-06-09 19:37 [Bug tree-optimization/101001] New: wrong code at -O3 on x86_64-linux-gnu qrzhang at gatech dot edu
2021-06-10 6:50 ` [Bug tree-optimization/101001] [9/10/11/12 Regression] " rguenth at gcc dot gnu.org
2021-06-10 7:26 ` rguenth at gcc dot gnu.org
2021-06-14 9:43 ` jakub at gcc dot gnu.org
2021-10-13 10:10 ` rguenth at gcc dot gnu.org
2021-11-09 7:57 ` pinskia at gcc dot gnu.org
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