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.

bool got() { return true; }
extern(C) int printf(char*, ...);
void main()
{
  bool b = true && got();
  printf("%d\n", b ? 1 : 0);
}