Compile-time check to make sure that there is no padding anywhere in a struct

Question

Is there a way to write a compile-time assertion that checks if some type has any padding in it?

For example:

struct This_Should_Succeed
{
    int a;         


        

Answer 1

Since C++17 you might be able to use std::has_unique_object_representations.

#include 

static_assert(std::has_unique_object_representations_v); // succeeds
static_assert(std::has_unique_object_representations_v); // fails

Although, this might not do exactly what you want it to do. Check the linked cppreference page for details.