Fixed ModuleInfo generation to no longer use the ModuleInfo class' default initializer for types/defaults, it's unsafe as initializers don't necesarily match the "formal" type. There might be explicit padding. Changed -g switch to emit DW_LANG_D debug info, make demangling work with a patched GDB, still more work to do for full support of D's Dwarf extensions. Added getNullValue helper method.

module bug15;

bool bool1(bool b) {
    if (b) return true;
    else return false;
}

bool bool2(bool b) {
    if (b) {return true;}
    else {return false;}
}

void main()
{
    assert(bool1(true));
    assert(!bool2(false));
}