Find holes in C structs due to alignment

Question

Is there a way in gcc or clang (or any other compiler) to spit information about whether a struct has holes (memory alignment - wise) in it ?

Thank you.

ps: If

Answer 1

One way of finding such holes without analyzing the source code and without adding checks to it (using offsetof() and the like) would be to extract the symbol/debug information from the object/executable/symbol files with some tool and look at the defined structures and members in them, their offsets and sizes and see if everything adds up. Unions will complicate things, though.