optimization/4311: unrolling loops creates non-ending loop

optimization/4311: unrolling loops creates non-ending loop

[guillaume.lemaitre33]

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>Number:         4311
>Category:       optimization
>Synopsis:       unrolling loops creates non-ending loop
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Wed Sep 12 13:16:01 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Guillaume Lemaître
>Release:        gcc-3.0.1
>Organization:
>Environment:
linux mandrake 8, duron 750 MHz
>Description:
see the source code attached.

a simple 'for' structure goes looping ever and ever
for special values of the upper bound

change the value of 'max' from -5 to -6 for example, and the
program will work
>How-To-Repeat:
gcc -O3 -Wall -funroll-all-loops -s comparaison.c -o comparaison
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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Re: optimization/4311: unrolling loops creates non-ending loop

[rth]

Synopsis: unrolling loops creates non-ending loop

Responsible-Changed-From-To: unassigned->rth
Responsible-Changed-By: rth
Responsible-Changed-When: Wed Apr  3 00:07:02 2002
Responsible-Changed-Why:
    .
State-Changed-From-To: open->closed
State-Changed-By: rth
State-Changed-When: Wed Apr  3 00:07:02 2002
State-Changed-Why:
    http://gcc.gnu.org/ml/gcc-patches/2002-04/msg00100.html

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=4311