--- cl.hpp.orig 2014-04-25 09:53:03.029286394 +0200 +++ cl.hpp 2014-04-25 09:55:06.330122827 +0200 @@ -212,8 +212,11 @@ #if defined(linux) || defined(__APPLE__) || defined(__MACOSX) #include +#ifdef __SSE2__ #include #include +#endif // __SSE2__ + #endif // linux #include @@ -1035,7 +1038,12 @@ #endif // !_WIN32 } +#ifdef __SSE2__ inline void fence() { _mm_mfence(); } +#else + inline void fence() {} +#endif + }; // namespace detail