diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index 466acc7..480a7b0 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -3,16 +3,19 @@ include_directories( playfair llhttp )
 
 # Common Linux cflags
 if ( UNIX AND NOT APPLE )
-  set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -O2 -DSTANDALONE -D__STDC_CONSTANT_MACROS -D__STDC_LIMIT_MACROS -DTARGET_POSIX -D_LINUX -fPIC -DPIC -D_REENTRANT -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -U_FORTIFY_SOURCE -Wall -g" )
+  set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DSTANDALONE -D__STDC_CONSTANT_MACROS -D__STDC_LIMIT_MACROS -DTARGET_POSIX -D_LINUX -fPIC -DPIC -D_REENTRANT -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -U_FORTIFY_SOURCE -Wall -g" )
 endif()
 
 
 # Common x86/x86_64 cflags
 if( NOT NO_MARCH_NATIVE AND CMAKE_SYSTEM_PROCESSOR MATCHES "(x86)|(X86)|(amd64)|(AMD64)" )
-  set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=native" )
+  set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Ofast -march=native" )
   message( STATUS "Using CFLAGS with  -march=native" )
   message( STATUS "*** ONLY USE THIS WHEN COMPILING ON THE MACHINE THAT WLL RUN UXPLAY" )
   message( STATUS "  run \"cmake -DNO_MARCH_NATIVE=ON\" to switch off this compiler option" )
+else()
+  message( STATUS "Not using -march=native" )
+  set( CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -O2" )
 endif()
 
 INCLUDE (CheckIncludeFiles)