Re: target/6981: wrong code in 64-bit manipulation on x86

Re: target/6981: wrong code in 64-bit manipulation on x86

[jakub]

Synopsis: wrong code in 64-bit manipulation on x86

Responsible-Changed-From-To: unassigned->jakub
Responsible-Changed-By: jakub
Responsible-Changed-When: Fri Jul 26 08:26:15 2002
Responsible-Changed-Why:
    Confirmed, debugging...

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=6981

Re: target/6981: wrong code in 64-bit manipulation on x86

[neroden]

Synopsis: wrong code in 64-bit manipulation on x86

State-Changed-From-To: open->closed
State-Changed-By: neroden
State-Changed-When: Thu Oct 24 12:00:18 2002
State-Changed-Why:
    Fixed on both mainline and 3.2.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=6981

target/6981: wrong code in 64-bit manipulation on x86

[Mattias Engdegård]

The following reply was made to PR target/6981; it has been noted by GNATS.

From: "=?ISO-8859-1?Q?Mattias Engdeg=E5rd?=" <mattias@virtutech.se>
To: gcc-gnats@gcc.gnu.org
Cc:  
Subject: target/6981: wrong code in 64-bit manipulation on x86
Date: Thu, 25 Jul 2002 17:00:23 +0200

 >The attach file also serves as a testcase, returning 0 if
 >the bug is present, 1 otherwise.
 
 No, it is the other way around.
 

Re: target/6981: wrong code in 64-bit manipulation on x86

[Mattias Engdegård]

The following reply was made to PR target/6981; it has been noted by GNATS.

From: "=?ISO-8859-1?Q?Mattias Engdeg=E5rd?=" <mattias@virtutech.se>
To: gcc-gnats@gcc.gnu.org, gcc-prs@gcc.gnu.org, gcc-bugs@gcc.gnu.org
Cc:  
Subject: Re: target/6981: wrong code in 64-bit manipulation on x86
Date: Tue, 16 Jul 2002 15:54:24 +0200

 I should make it clear that this is a regression from gcc 3.0.x, so someone
 may want to elevate the priority.
 

target/6981: wrong code in 64-bit manipulation on x86

[mattias]

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>Number:         6981
>Category:       target
>Synopsis:       wrong code in 64-bit manipulation on x86
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Mon Jun 10 02:56:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Mattias Engdegård
>Release:        gcc version 3.1
>Organization:
>Environment:
redhat 6.2 host (x86)
>Description:
gcc 3.1 (x86 target) generates wrong code when the attached
file is compiled with -O2. The error is in the bar() function.
The attach file also serves as a testcase, returning 0 if
the bug is present, 1 otherwise.

(What makes the problem severe is that the wrong code is
generated silently and the exact circumstances unknown, so
we are going back to 3.0.4 meanwhile.)
>How-To-Repeat:
Compile the attached file with -O2, using plain gcc 3.1 for
x86, built from source with a default configuration.
>Fix:
Use a lower optimisation level than -O2
>Release-Note:
>Audit-Trail:
>Unformatted:
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Content-Disposition: attachment; filename="sr1.c"

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