c/6917: optimization problem in gcc 3.1

c/6917: optimization problem in gcc 3.1

[valera.veryazov]

>Number:         6917
>Category:       c
>Synopsis:       optimization problem in gcc 3.1
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jun 03 05:26:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Valera Veryazov
>Release:        gcc 3.1
>Organization:
>Environment:
Linux Mandrake 8.2
>Description:
the code is working well under gcc 3.0.4,
but give different results under gcc 3.1
with -O2 and -O1 flags.

#include <stdio.h>
void main (void)
{
   char     magic[8] = { 0x7f , 'A' , 'B' , 'C' , 'D' , 'E' , 'F' , 0x7f };
   int     *MAGIC;
   MAGIC = (int *)(&magic[0]);
   printf (">> %d \n",*MAGIC);
   return;
}
>How-To-Repeat:
compile the code with -O2 and -O1 options for gcc 3.1
>Fix:

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