[Bug target/57341] New: wrong code on x86_64-linux at -O3 in 32-bit mode

[dhazeghi at yahoo dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57341

            Bug ID: 57341
           Summary: wrong code on x86_64-linux at -O3 in 32-bit mode
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dhazeghi at yahoo dot com

The following code is miscompiled on gcc trunk and 4.8 branch on
x86_64-linux-gnu, at -O3 optimization level, in 32-bit mode, resulting in
output of 0 rather than 1.  It is compiled correctly at all optimization levels
with gcc 4.7.

$ gcc-trunk -v
gcc version 4.9.0 20130520 (experimental) [trunk revision 199099] (GCC) 
$ gcc-trunk -O2 -m32 wrong.c 
$ ./a.out 
1
$ gcc-trunk -O3 -m64 wrong.c 
$ ./a.out 
1
$ gcc-4.7 -O3 -m32 wrong.c 
$ ./a.out 
1
$ gcc-trunk -O3 -m32 wrong.c 
$ ./a.out 
0

-------------------------------
int printf(const char *, ...);
int a, d;
int *b = &a, **c;
int main ()
{
    int e;
    {
        int f[4];
        for (d = 0; d < 4; d++)
            f[d] = 1;
        e = f[1];
    }
    int *g[28] = { };
    *b = e;
    c = &g[0];
    printf ("%d\n", a);
    return 0;
}