Re: fortran/5837: bug in loop unrolling

Re: fortran/5837: bug in loop unrolling

[toon]

Synopsis: bug in loop unrolling

Responsible-Changed-From-To: unassigned->toon
Responsible-Changed-By: toon
Responsible-Changed-When: Sat Apr 13 07:23:52 2002
Responsible-Changed-Why:
    My job
State-Changed-From-To: open->closed
State-Changed-By: toon
State-Changed-When: Sat Apr 13 07:23:52 2002
State-Changed-Why:
    Apparently fixed for 3.1

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=5837

fortran/5837: bug in loop unrolling

[Valera.Veryazov]

>Number:         5837
>Category:       fortran
>Synopsis:       bug in loop unrolling
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Mar 05 05:46:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Valera.Veryazov@teokem.lu.se
>Release:        3.0.4
>Organization:
>Environment:
Linux Mandrake 8.1. GCC/G77 compiled from the source code.
>Description:
The code (see attachment) produces a Segnematation fault,
if flags " -O  -funroll-loops" are used.

Change of parameter to 12, 16 gives a correct result.
Also, a change of declaration Character *64 to, say,
Character*45 produces a funny number instead 0.

Removing -unroll-loops flag or using unrolling by hands
also 'fix' the problem.

>How-To-Repeat:
just compile the code with -O  -funroll-loops flags.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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