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* [Bug c/21688] New: gcc miscompiles with -Os (wrong code at least on i386, x86_64 and ppc)
@ 2005-05-20 22:24 felix-gcc at fefe dot de
2005-05-20 22:43 ` [Bug middle-end/21688] [4.0 Regression] " pinskia at gcc dot gnu dot org
2005-05-20 23:02 ` [Bug middle-end/21688] [4.0 Regression] gcc miscompiles with -funit-at-a-time pinskia at gcc dot gnu dot org
0 siblings, 2 replies; 3+ messages in thread
From: felix-gcc at fefe dot de @ 2005-05-20 22:24 UTC (permalink / raw)
To: gcc-bugs
wget http://dl.fefe.de/crypt-bug.c
gcc4 -Os -o t crypt-bug.c
./t
# assertion failure
gcc4 -O -o t crypt-bug.c
./t
# works ok
reproduced on i386, x86_64 and using Apple's gcc 4 in Tiger.
--
Summary: gcc miscompiles with -Os (wrong code at least on i386,
x86_64 and ppc)
Product: gcc
Version: 4.0.0
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: felix-gcc at fefe dot de
CC: gcc-bugs at gcc dot gnu dot org
GCC build triplet: x86_64-linux
GCC host triplet: x86_64-linux
GCC target triplet: x86_64-linux
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21688
^ permalink raw reply [flat|nested] 3+ messages in thread* [Bug middle-end/21688] [4.0 Regression] gcc miscompiles with -Os (wrong code at least on i386, x86_64 and ppc)
2005-05-20 22:24 [Bug c/21688] New: gcc miscompiles with -Os (wrong code at least on i386, x86_64 and ppc) felix-gcc at fefe dot de
@ 2005-05-20 22:43 ` pinskia at gcc dot gnu dot org
2005-05-20 23:02 ` [Bug middle-end/21688] [4.0 Regression] gcc miscompiles with -funit-at-a-time pinskia at gcc dot gnu dot org
1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-05-20 22:43 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-05-20 22:43 -------
Hmm, the assmbley for the functions at -O and -O -funit-at-a-time are no different but we get wrong
code some how.
This works on the mainline and in 3.4.0 so it is a regression.
--
What |Removed |Added
----------------------------------------------------------------------------
CC| |hubicka at gcc dot gnu dot
| |org
Component|c |middle-end
Keywords| |wrong-code
Known to fail| |4.0.0
Known to work| |3.4.0 4.1.0
Summary|gcc miscompiles with -Os |[4.0 Regression] gcc
|(wrong code at least on |miscompiles with -Os (wrong
|i386, x86_64 and ppc) |code at least on i386,
| |x86_64 and ppc)
Target Milestone|--- |4.0.1
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21688
^ permalink raw reply [flat|nested] 3+ messages in thread* [Bug middle-end/21688] [4.0 Regression] gcc miscompiles with -funit-at-a-time
2005-05-20 22:24 [Bug c/21688] New: gcc miscompiles with -Os (wrong code at least on i386, x86_64 and ppc) felix-gcc at fefe dot de
2005-05-20 22:43 ` [Bug middle-end/21688] [4.0 Regression] " pinskia at gcc dot gnu dot org
@ 2005-05-20 23:02 ` pinskia at gcc dot gnu dot org
1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-05-20 23:02 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-05-20 23:02 -------
Oh, even at -O0 -funit-at-a-time, we get this missed compiled.
There are buffer overflows somewhere:
*******
mudflap violation 1 (check/write): time=1116629904.932813 ptr=0x80ce540 size=33
pc=0x45b4a8 location=`crypt-bug.c:206 (encrypt)'
/home/peshtigo/pinskia/linux/lib/libmudflap.so.0(__mf_check+0x48) [0x45b4a8]
./a.out(encrypt+0x1c7) [0x80499c4]
./a.out(crypt+0xaaf) [0x804be45]
Nearby object 1: checked region begins 0B into and ends 1B after
mudflap object 0xa095a08: name=`crypt-bug.c:190 L'
bounds=[0x80ce540,0x80ce55f] size=32 area=static check=0r/4w liveness=4
alloc time=1116629904.932154 pc=0x45bfe8
Nearby object 2: checked region begins 32B before and ends 0B into
mudflap object 0xa095a70: name=`crypt-bug.c:190 R'
bounds=[0x80ce560,0x80ce57f] size=32 area=static check=0r/3w liveness=3
alloc time=1116629904.932158 pc=0x45bfe8
number of nearby objects: 2
Fixing that I get a different the abort, can you double check to make sure this code is really valid, from
the looks of it, it is not.
The code is assuming that L and R come right after each in memory, and that is a false assumption.
--
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution| |INVALID
Summary|[4.0 Regression] gcc |[4.0 Regression] gcc
|miscompiles with -Os (wrong |miscompiles with -funit-at-
|code at least on i386, |a-time
|x86_64 and ppc) |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21688
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2005-05-20 23:02 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2005-05-20 22:24 [Bug c/21688] New: gcc miscompiles with -Os (wrong code at least on i386, x86_64 and ppc) felix-gcc at fefe dot de
2005-05-20 22:43 ` [Bug middle-end/21688] [4.0 Regression] " pinskia at gcc dot gnu dot org
2005-05-20 23:02 ` [Bug middle-end/21688] [4.0 Regression] gcc miscompiles with -funit-at-a-time pinskia at gcc dot gnu dot org
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