diff --git a/CMakeLists.txt b/CMakeLists.txt
index e0e3b7bc..8281129a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -199,8 +199,8 @@ if(CMAKE_SIZEOF_VOID_P EQUAL 8)
 	set(BITS 64)
 endif(CMAKE_SIZEOF_VOID_P EQUAL 8)
 
-string(TOLOWER ${CMAKE_SYSTEM_NAME} SYSTEM_NAME)
-string(TOLOWER ${CMAKE_BUILD_TYPE} BUILD_TYPE)
+string(TOLOWER "${CMAKE_SYSTEM_NAME}" SYSTEM_NAME)
+string(TOLOWER "${CMAKE_BUILD_TYPE}" BUILD_TYPE)
 
 if(ANDROID)
 	# Added the android abi after system name