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optimization/5800: gcc -O0 produces wrong code
- From: Mikhail dot Jabitski at cern dot ch
- To: gcc-gnats at gcc dot gnu dot org
- Date: 1 Mar 2002 11:41:58 -0000
- Subject: optimization/5800: gcc -O0 produces wrong code
- Reply-to: Mikhail dot Jabitski at cern dot ch
>Number: 5800
>Category: optimization
>Synopsis: gcc -O0 produces wrong code
>Confidential: no
>Severity: serious
>Priority: high
>Responsible: unassigned
>State: open
>Class: wrong-code
>Submitter-Id: net
>Arrival-Date: Fri Mar 01 03:46:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator: gcc
>Release: 3.0.4
>Organization:
>Environment:
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ../gcc-3.0.4/configure
>Description:
gcc with optimization -O0 produces wrong code for the file comp.c:
#include <stdlib.h>
int main()
{
int a[] = { 1, 1};
printf("%i %i\n",a[0],a[1]);
a[1] = a[0] && a[1];
printf("%i %i\n",a[0],a[1]);
return(1);
}
Compiled with:
gcc -O0 comp.c
Program output:
1 1
1 0
Which is definitely wrong ("1 1" expected)
>How-To-Repeat:
Compile attached file with gcc -O0 comp.c and see results
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
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