Hi all, What compiler flags are allowed for optimization with gcc in debian unstable/testing? My project has got support for builtin vector functions. And we don't enable any compiler flags to architecture specific CPU extensions. https://salsa.debian.org/multimedia-team/gsequencer/blob/master/debian/rules Learn more about vectors: https://www.linuxjournal.com/content/introduction-gcc-compiler-intrinsics-vector-processing cheers, Joël