https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84863
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Never use -Werror with -fsanitize=*, those really do cause new warnings because the code intentionally is less optimized and the runtime check themselves prevent further optimizations, so warnings that depend on optimizations can't work properly.
