Index: head/astro/oskar/files/patch-extern_Random123_features_gccfeatures.h
===================================================================
--- head/astro/oskar/files/patch-extern_Random123_features_gccfeatures.h
+++ head/astro/oskar/files/patch-extern_Random123_features_gccfeatures.h
@@ -0,0 +1,32 @@
+--- extern/Random123/features/gccfeatures.h.orig	2019-11-17 00:45:21 UTC
++++ extern/Random123/features/gccfeatures.h
+@@ -60,7 +60,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY O
+  Please let the authors know of any successes (or failures). */
+ #endif
+ 
+-#ifdef __powerpc__
++#if defined(__powerpc__) && !defined(__clang__)
+ #include <ppu_intrinsics.h>
+ #endif
+ 
+@@ -246,6 +246,20 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY O
+ #else
+ #define R123_USE_MULHILO64_MULHI_INTRIN 0
+ #endif
++#endif
++
++#if defined(__powerpc__) && defined(__clang__)
++#ifdef __powerpc64__
++static inline unsigned long long __mulhdu(unsigned long long a, unsigned long long b) {
++  __uint128_t c = (__uint128_t) a * (__uint128_t) b;
++  return c >> 64;
++}
++#endif
++
++static inline unsigned int __mulhwu(unsigned int a, unsigned int b) {
++  unsigned long long c = (unsigned long long) a * (unsigned long long) b;
++  return c >> 32;
++}
+ #endif
+ 
+ #ifndef R123_MULHILO64_MULHI_INTRIN