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 scope5;

int i;

void func(int a, int b)
{
    i = 0;
    {
        scope(exit) i++;
        if (a) {
            scope(exit) i++;
            if (b) return;
            i++;
        }
    }
    i++;
}

void main()
{
    func(0,0);
    assert(i == 2);
    func(1,1);
    assert(i == 2);
    func(1,0);
    assert(i == 4);
}