Merge pull request #22 from barracuda156/ppc

Do not use invalid -march= flag on PPC, fix the build

Author: karypis

GKlibSystem.cmake

@@ -33,8 +33,13 @@ if(CMAKE_COMPILER_IS_GNUCC)
   set(GKlib_COPTIONS "${GKlib_COPTIONS} -std=c99 -fno-strict-aliasing")
 if(VALGRIND)
   set(GKlib_COPTIONS "${GK_COPTIONS} -march=x86-64 -mtune=generic")
+else()
+# -march=native is not a valid flag on PPC:
+if(CMAKE_SYSTEM_PROCESSOR MATCHES "power|ppc|powerpc|ppc64|powerpc64" OR (APPLE AND CMAKE_OSX_ARCHITECTURES MATCHES "ppc|ppc64"))
+  set(GKlib_COPTIONS "${GKlib_COPTIONS} -mtune=native")
 else()
   set(GKlib_COPTIONS "${GKlib_COPTIONS} -march=native")
+endif()
 endif(VALGRIND)
   if(NOT MINGW)
       set(GKlib_COPTIONS "${GKlib_COPTIONS} -fPIC")