Strange behaviour of gcc on my 64-bit Pentium Core 2 Duo

["Ravi kumar" <ravi dot kumar dot 039 at gmail dot com>]

I tried to compile gcc on my machine running Ubuntu-7.04 AMD-64
(linux), but the make stops in the middle and says, it can't find
<gnu/stubs-32.h>.
On looking into the files stubs.h and <bits/wordsize.h> I found that
stubs-64.h should be include if __x86_64__ is defined, but it doesn't.

Then i wrote a simple program :-

//============================
============
#include <stdio.h>
#include <gnu/stubs.h>

int main() {
       #ifdef __x86_64__
                printf("\n====Good !\n\n");
       #else
                printf("\n====Bad and Ugly !\n\n");
        #endif
       return 0;
}
//=========================================

and the output I got is this:-

====Good !

which means that __x86_64__ is  defined, but I can't understand why
the make complains while compling gcc ??

I would very much appreciate a solution....but even if anyone gives me
a hint about what  maybe wrong i will appreciate that too !