Is padding specified by the spec? Because if it's not then padding won't help you either since you don't know that your padding aligns with the compiler's. Rath

Is padding specified by the spec? Because if it's not then padding won't help you either since you don't know that your padding aligns with the compiler's. Rather AFAIK you need to write some compile time checks that what you think the compiler is going to do is what it does and fail compilation if doesn't and then add whatever compiler/platform/option specific code to get your stuff to match along with more tests.