https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69680
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Jeff Hammond from comment #0) > It seems that none of the GCC 5.3.0 headers declare this function... Because GCC doesn't provide a C library, it uses the one from your OS. Presumably it doesn't support C11, or at least not aligned_alloc.
