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* Re: optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3
@ 2002-10-07 4:56 Richard Henderson
0 siblings, 0 replies; 6+ messages in thread
From: Richard Henderson @ 2002-10-07 4:56 UTC (permalink / raw)
To: nobody; +Cc: gcc-prs
The following reply was made to PR optimization/8156; it has been noted by GNATS.
From: Richard Henderson <rth@redhat.com>
To: Andreas Steinmetz <ast@domdv.de>
Cc: gcc-gnats@gcc.gnu.org, gcc-prs@gcc.gnu.org, bregor@anusf.anu.edu.au,
gcc-bugs@gcc.gnu.org, nobody@gcc.gnu.org
Subject: Re: optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3
Date: Mon, 7 Oct 2002 04:51:31 -0700
On Mon, Oct 07, 2002 at 01:13:19PM +0200, Andreas Steinmetz wrote:
> As it seems that "-fomit-frame-pointer" does trigger the problems it
> could well be that there is a gcc bug.
All of this is confused by the fact that someone sent
stuff to the gcc-bugs list by repling to an unrelated
bug posting. Blah.
r~
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3
@ 2003-05-14 10:27 giovannibajo
0 siblings, 0 replies; 6+ messages in thread
From: giovannibajo @ 2003-05-14 10:27 UTC (permalink / raw)
To: bregor, gcc-bugs, gcc-prs, nobody
Synopsis: -mcpu=pentium4 generates wrong fp results in glibc-2.3
State-Changed-From-To: open->analyzed
State-Changed-By: bajo
State-Changed-When: Wed May 14 10:27:01 2003
State-Changed-Why:
See Dara's question.
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8156
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3
@ 2003-05-13 18:46 Dara Hazeghi
0 siblings, 0 replies; 6+ messages in thread
From: Dara Hazeghi @ 2003-05-13 18:46 UTC (permalink / raw)
To: nobody; +Cc: gcc-prs
The following reply was made to PR optimization/8156; it has been noted by GNATS.
From: Dara Hazeghi <dhazeghi@yahoo.com>
To: bregor@anusf.anu.edu.au, gcc-gnats@gcc.gnu.org, nobody@gcc.gnu.org
Cc:
Subject: Re: optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3
Date: Tue, 13 May 2003 11:38:24 -0700
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-
trail&database=gcc&pr=8156
Hello,
sorry to see that this never got resolved (at least not according to
GNATS). Would it be possible for you to try gcc 3.3 prerelease, and see
if the same problem still occurs? There have been a lot of changes, and
at least some linux distros are using 3.3 (cvs) to build glibc and
other stuff. Thanks,
Dara
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3
@ 2002-10-07 4:16 Andreas Steinmetz
0 siblings, 0 replies; 6+ messages in thread
From: Andreas Steinmetz @ 2002-10-07 4:16 UTC (permalink / raw)
To: nobody; +Cc: gcc-prs
The following reply was made to PR optimization/8156; it has been noted by GNATS.
From: Andreas Steinmetz <ast@domdv.de>
To: gcc-gnats@gcc.gnu.org, gcc-prs@gcc.gnu.org, bregor@sf.anu.edu.au,
gcc-bugs@gcc.gnu.org, nobody@gcc.gnu.org
Cc:
Subject: Re: optimization/8156: -mcpu=pentium4 generates wrong fp results
in glibc-2.3
Date: Mon, 07 Oct 2002 13:13:19 +0200
> This is a glibc bug, not a gcc bug.
I'm not so sure that it is a problem of glibc only. In my case building
glibc 2.3 with gcc 3.2 (release)/binutils 2.13 (release) succeeds in all
cases but:
1. CFLAGS="-O3 -mcpu=pentiumpro -march=pentiumpro" produces a working
glibc
2. CFLAGS="-O3 -fomit-frame-pointer -mcpu=pentiumpro -march=pentiumpro"
produces a glibc with defunct pthreads (hangs and segfaults of
threaded processes), strace-ing these processes indicate defunct
signal handling
As it seems that "-fomit-frame-pointer" does trigger the problems it
could well be that there is a gcc bug.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3
@ 2002-10-06 21:46 Andreas Jaeger
0 siblings, 0 replies; 6+ messages in thread
From: Andreas Jaeger @ 2002-10-06 21:46 UTC (permalink / raw)
To: nobody; +Cc: gcc-prs
The following reply was made to PR optimization/8156; it has been noted by GNATS.
From: Andreas Jaeger <aj@suse.de>
To: bregor@sf.anu.edu.au
Cc: gcc-gnats@gcc.gnu.org
Subject: Re: optimization/8156: -mcpu=pentium4 generates wrong fp results in
glibc-2.3
Date: Mon, 07 Oct 2002 06:45:15 +0200
bregor@sf.anu.edu.au writes:
>>Number: 8156
>>Category: optimization
>>Synopsis: -mcpu=pentium4 generates wrong fp results in glibc-2.3
>>Confidential: no
>>Severity: serious
>>Priority: medium
>>Responsible: unassigned
>>State: open
>>Class: wrong-code
>>Submitter-Id: net
>>Arrival-Date: Sun Oct 06 20:06:01 PDT 2002
>>Closed-Date:
>>Last-Modified:
>>Originator: Roger Brown
>>Release: gcc (GCC) 3.2.1 20021004 (prerelease)
>>Organization:
>>Environment:
> Linux-2.4.19-pre10
> HJL's binutils-2.13.90.0.4
> glibc-2.3 release source code
>>Description:
> *** This may be a duplicate report but the original seems
> to have got lost.
>
> After building the released source for glibc-2.3,
> with "gcc (GCC) 3.2.1 20021004 (prerelease)", and the
> -mcpu=pentium4 -march=pentium4 switches, make check
> discovered many serious errors for the floating-point
> special functions (see below). The same build, with
> -mcpu=i686 -march=i686 failed with an assembler error.
Can you send information about the assembler error? Do you have a
small testcase for this?
> With -mcpu and -march left at the default values, both
> the build and check are clean.
>
> Other software details: O/S linux-2.4.19-pre10 and
> HJL's Linux-binutils-2.13.90.0.4.
>
> The actual "check" failure was:
>
> GCONV PATH=/Main/Glibc/glibc-2.3/Build/iconvdata LC ALL=C
> /Main/Glibc/glibc-2.3/Build/elf/ld-linux.so.2 --library-path
> /Main/Glibc/glibc-2.3/Build:/Main/Glibc/glibc-2.3/Build/math:
> /Main/Glibc/glibc-2.3/Build/elf:/Main/Glibc/glibc-2.3/Build/dlfcn:
> /Main/Glibc/glibc-2.3/Build/nss:/Main/Glibc/glibc-2.3/Build/nis:
> /Main/Glibc/glibc-2.3/Build/rt:/Main/Glibc/glibc-2.3/Build/resolv:
> /Main/Glibc/glibc-2.3/Build/crypt:/Main/Glibc/glibc-2.3/Build/linuxthreads
> /Main/Glibc/glibc-2.3/Build/math/test-idouble >
> /Main/Glibc/glibc-2.3/Build/math/test-idouble.out
> make[2]: *** [/Main/Glibc/glibc-2.3/Build/math/test-idouble.out] Error 139
A segmentation fault as result of test-idouble.out? That's strange.
> The errors reported in test-idouble.out are alarming !
> The first part reads:
>
> testing double (without inline functions)
> Failure: Test: cosh (0.75) == 1.29468328467684468784170818539018176
> Result:
> is: 2.11700001661267478426e+00 0x1.0ef9db467dcf80000000p+1
> should be: 1.29468328467684479222e+00 0x1.4b705d1e5d6a80000000p+0
> difference: 8.22316731935829992040e-01 0x1.a506b2dd3c6900000000p-1
> ulp : 3703385327526728.0000
> max.ulp : 0.0000
Can you nail down what goes wrong? Is cosh miscompiled (the source is
in sysdeps/ieee754/dbl-64/e_cosh.c) or one of the functions it's
calling?
> Maximal error of `cosh'
> is : 3703385327526728 ulp
> accepted: 0 ulp
> Failure: sinh (-inf) == -inf: Exception "Invalid operation" set
> Failure: Test: sinh (-inf) == -inf
> Result:
> is: nan nan
> should be: -inf -inf
> Failure: Test: sinh (0.75) == 0.822316731935829980703661634446913849
>
> and it gets much worse, much worse !!
>
> Specific *.i files etc can be provided.
Andreas
--
Andreas Jaeger
SuSE Labs aj@suse.de
private aj@arthur.inka.de
http://www.suse.de/~aj
^ permalink raw reply [flat|nested] 6+ messages in thread
* optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3
@ 2002-10-06 20:06 bregor
0 siblings, 0 replies; 6+ messages in thread
From: bregor @ 2002-10-06 20:06 UTC (permalink / raw)
To: gcc-gnats
>Number: 8156
>Category: optimization
>Synopsis: -mcpu=pentium4 generates wrong fp results in glibc-2.3
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: unassigned
>State: open
>Class: wrong-code
>Submitter-Id: net
>Arrival-Date: Sun Oct 06 20:06:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator: Roger Brown
>Release: gcc (GCC) 3.2.1 20021004 (prerelease)
>Organization:
>Environment:
Linux-2.4.19-pre10
HJL's binutils-2.13.90.0.4
glibc-2.3 release source code
>Description:
*** This may be a duplicate report but the original seems
to have got lost.
After building the released source for glibc-2.3,
with "gcc (GCC) 3.2.1 20021004 (prerelease)", and the
-mcpu=pentium4 -march=pentium4 switches, make check
discovered many serious errors for the floating-point
special functions (see below). The same build, with
-mcpu=i686 -march=i686 failed with an assembler error.
With -mcpu and -march left at the default values, both
the build and check are clean.
Other software details: O/S linux-2.4.19-pre10 and
HJL's Linux-binutils-2.13.90.0.4.
The actual "check" failure was:
GCONV PATH=/Main/Glibc/glibc-2.3/Build/iconvdata LC ALL=C
/Main/Glibc/glibc-2.3/Build/elf/ld-linux.so.2 --library-path
/Main/Glibc/glibc-2.3/Build:/Main/Glibc/glibc-2.3/Build/math:
/Main/Glibc/glibc-2.3/Build/elf:/Main/Glibc/glibc-2.3/Build/dlfcn:
/Main/Glibc/glibc-2.3/Build/nss:/Main/Glibc/glibc-2.3/Build/nis:
/Main/Glibc/glibc-2.3/Build/rt:/Main/Glibc/glibc-2.3/Build/resolv:
/Main/Glibc/glibc-2.3/Build/crypt:/Main/Glibc/glibc-2.3/Build/linuxthreads
/Main/Glibc/glibc-2.3/Build/math/test-idouble >
/Main/Glibc/glibc-2.3/Build/math/test-idouble.out
make[2]: *** [/Main/Glibc/glibc-2.3/Build/math/test-idouble.out] Error 139
The errors reported in test-idouble.out are alarming !
The first part reads:
testing double (without inline functions)
Failure: Test: cosh (0.75) == 1.29468328467684468784170818539018176
Result:
is: 2.11700001661267478426e+00 0x1.0ef9db467dcf80000000p+1
should be: 1.29468328467684479222e+00 0x1.4b705d1e5d6a80000000p+0
difference: 8.22316731935829992040e-01 0x1.a506b2dd3c6900000000p-1
ulp : 3703385327526728.0000
max.ulp : 0.0000
Maximal error of `cosh'
is : 3703385327526728 ulp
accepted: 0 ulp
Failure: sinh (-inf) == -inf: Exception "Invalid operation" set
Failure: Test: sinh (-inf) == -inf
Result:
is: nan nan
should be: -inf -inf
Failure: Test: sinh (0.75) == 0.822316731935829980703661634446913849
and it gets much worse, much worse !!
Specific *.i files etc can be provided.
>How-To-Repeat:
Build glibc-2.3 with -mcpu=pentium4 -march=pentium4
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2003-05-14 10:27 UTC | newest]
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2002-10-07 4:56 optimization/8156: -mcpu=pentium4 generates wrong fp results in glibc-2.3 Richard Henderson
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2003-05-14 10:27 giovannibajo
2003-05-13 18:46 Dara Hazeghi
2002-10-07 4:16 Andreas Steinmetz
2002-10-06 21:46 Andreas Jaeger
2002-10-06 20:06 bregor
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