diff --git a/CMakeLists.txt b/CMakeLists.txt
index 84d2c1d0..5925d5fe 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -129,7 +129,7 @@ endif()
 if(CMAKE_COMPILER_IS_GNUCXX)
 	#add_definitions(-S)
 	#add_definitions(-s)
-	add_definitions(-m32)
+	add_definitions(-m64)
 	add_definitions(-O2)
 
 	#add_definitions(-fprofile-arcs -ftest-coverage) gcov