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* [Bug c/53656] New: sequence point bug
@ 2012-06-13 12:09 alexcheremkhin at gmail dot com
2012-06-13 12:47 ` [Bug c/53656] " joseph at codesourcery dot com
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: alexcheremkhin at gmail dot com @ 2012-06-13 12:09 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53656
Bug #: 53656
Summary: sequence point bug
Classification: Unclassified
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: alexcheremkhin@gmail.com
Created attachment 27614
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27614
source code
$gcc -v
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/i686-pc-linux-gnu/4.6.0/lto-wrapper
Целевая архитектура: i686-pc-linux-gnu
Параметры конфигурации: ./configure
Модель многопоточности: posix
gcc версия 4.6.0 (GCC)
Optimization options do not matter (result is the same).
Source code:
----------------------------------------------------
/* bug.c */
#include <stdio.h>
int x = 0;
int f()
{
return x++;
}
int main()
{
int y = x++ + f();
printf("x=%d\n", x);
return 0;
}
------------------------------------------------------
The program should have printed 'x=2', but prints 'x=1'.
It looks like the variable x had been read to a register before call of f(),
and incremented after the call.
The function call makes a sequence point, so the behaviuor is not correct.
Alexey Cheremkhin; Compiler Department, KM211.
avc@km211.ru
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/53656] sequence point bug
2012-06-13 12:09 [Bug c/53656] New: sequence point bug alexcheremkhin at gmail dot com
@ 2012-06-13 12:47 ` joseph at codesourcery dot com
2012-06-14 15:38 ` alexcheremkhin at gmail dot com
2012-06-14 17:55 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: joseph at codesourcery dot com @ 2012-06-13 12:47 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53656
--- Comment #1 from joseph at codesourcery dot com <joseph at codesourcery dot com> 2012-06-13 12:47:23 UTC ---
Looks similar to bug 48814.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/53656] sequence point bug
2012-06-13 12:09 [Bug c/53656] New: sequence point bug alexcheremkhin at gmail dot com
2012-06-13 12:47 ` [Bug c/53656] " joseph at codesourcery dot com
@ 2012-06-14 15:38 ` alexcheremkhin at gmail dot com
2012-06-14 17:55 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: alexcheremkhin at gmail dot com @ 2012-06-14 15:38 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53656
--- Comment #2 from Alexey Cheremkhin <alexcheremkhin at gmail dot com> 2012-06-14 15:38:36 UTC ---
(In reply to comment #1)
> Looks similar to bug 48814.
Thank you very much.
It is definitely the same bug.
Bug 48814 was fixed on 2012-03-16, so I simply used the patch.
Alexey Cheremkhin; Compiler Department, KM211.
avc@km211.ru
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/53656] sequence point bug
2012-06-13 12:09 [Bug c/53656] New: sequence point bug alexcheremkhin at gmail dot com
2012-06-13 12:47 ` [Bug c/53656] " joseph at codesourcery dot com
2012-06-14 15:38 ` alexcheremkhin at gmail dot com
@ 2012-06-14 17:55 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2012-06-14 17:55 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53656
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution| |DUPLICATE
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-06-14 17:55:28 UTC ---
Closing as a dup then.
*** This bug has been marked as a duplicate of bug 48814 ***
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2012-06-14 17:55 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2012-06-13 12:09 [Bug c/53656] New: sequence point bug alexcheremkhin at gmail dot com
2012-06-13 12:47 ` [Bug c/53656] " joseph at codesourcery dot com
2012-06-14 15:38 ` alexcheremkhin at gmail dot com
2012-06-14 17:55 ` pinskia at gcc dot gnu.org
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