Fixed a nasty bug with how interface vtables for class initializers were output, causing some class fields to be skipped. Fixed a problem in definition of ClassInfos where an invalid constant was potentially used. This needs to be looked into proper as it might happen again in the future.

module bug17;

struct Vec
{
    Vec opAdd(ref Vec b) { return Vec(); }
    Vec opMul(double a) { return Vec(); }
}
void main()
{
    Vec foo;
    Vec bar;
    auto whee=foo+bar*1f;
}