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 vararg2;

void func(...)
{
    assert(_arguments.length == 2);
    assert(_arguments[0] is typeid(int));
    int a = *cast(int*)_argptr;
    _argptr += size_t.sizeof;
    assert(_arguments[1] is typeid(int));
    a += *cast(int*)_argptr;
    _argptr += int.sizeof;
    assert(a == 3);
}

void main()
{
    func(1,2);
}