Changed some hardcoded offset/alignment for classes in DMD, broke offsets for 64bits. Changed ClassInfo generation to no longer access the default initializer of ClassInfo, fixes problems with index mismatch.

module bug64;

void main()
{
    float f;
    float* p = &f;
    float* end1 = p+1;
    float* end2 = 1+p;
    assert(end1 is end2);
}