https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89464
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|WAITING |RESOLVED Resolution|--- |INVALID --- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Someone is doing: #define alignas(x) __attribute__((aligned(x))) Which is not valid as alignas does take a type name also. You can figure out who by adding -g3 (with -save-temps still) and looking at the .ii file to see who defines it. Easies way to fix this is to reorder the header files: #include "HDHomeRunTuners.h" #include <cstring> #include <ctime> #include <functional> #include <memory> #include <set> #include <string> #include <vector> So the system ones are included first. But this is not a GCC issue.