https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61458
--- Comment #4 from Paolo Carlini <paolo.carlini at oracle dot com> --- Hi Jon. Frankly Are you 100% sure (in terms of middle-end/back-end details) that the maximum alignment supported for a type of less than 4 bytes is 4? In that case, your proposal of using __aligned__((_Len)) certainly makes sense. I wasn't sure at the time and picked a "safe" choice, probably should have asked...