[Bug c++/17581] Long long arithmetic fails inside a switch/case statement when compiled with -O2

["alottem at yahoo dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From alottem at yahoo dot com  2004-09-21 12:22 -------
The test case was further minimized to the following:

------------------------ cut here ------------------------
#include <stdio.h>

int
f(long unsigned x1)
{
        unsigned long long ctl_bitvec = 0;

        switch(x1) {
        case 21:
                ctl_bitvec |= 1;
                ctl_bitvec |= 2;
                ctl_bitvec |= 8;
                break;
        default:
                break;
        }

        printf("%llx\n", ctl_bitvec);
        return ctl_bitvec;
}


main() {
        f(21);
}
------------------------ cut here ------------------------

And running:
% make && make run
/usr/intel/pkgs/gcc/3.4/bin/g++ -O2 test.c -o test_o2
/usr/intel/pkgs/gcc/3.4/bin/g++ -O test.c -o test_o
./test_o2
8
./test_o
b

It does not fail with gcc 3.3.2.  unfortunately, I was not able to test with 
versions later than 3.4.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17581