[Bug c/112539] a struct with an array of unknown size at the end allows writing past end of the struct

[sjames at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112539

--- Comment #2 from Sam James <sjames at gcc dot gnu.org> ---
https://people.kernel.org/kees/bounded-flexible-arrays-in-c and
https://developers.redhat.com/articles/2022/09/29/benefits-limitations-flexible-array-members
are good reads too