https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115539
--- Comment #6 from Sam James <sjames at gcc dot gnu.org> --- (In reply to Sam James from comment #5) > fastreadl_fetch in particular looks aliasing unsafe, let alone the rest. The code looks derived from 86box or similar. They build with -fno-strict-aliasing: https://github.com/86Box/86Box/blob/15d2ee28c7d7f4590f1f69c542081cdb78313b91/cmake/flags-gcc.cmake#L18. You should be building with it too if using code derived from it.