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.

extern(C) int printf(char*, ...);
void main()
{
    void* i;
    asm
    {
        mov EAX, FS:4;
        mov i, EAX;
    }
    printf("FS:4 = %p\n", i);
}