diff --git a/lib/tolua++/CMakeLists.txt b/lib/tolua++/CMakeLists.txt
index 7e7498411..e5c8ce3e8 100644
--- a/lib/tolua++/CMakeLists.txt
+++ b/lib/tolua++/CMakeLists.txt
@@ -9,7 +9,7 @@ include_directories ("${PROJECT_SOURCE_DIR}")
 
 find_program(XXD_EXECUTABLE xxd)
 
-if(NOT XXD_EXECUTABLE STREQUAL "xxd-NOTFOUND")
+if(NOT XXD_EXECUTABLE STREQUAL "XXD_EXECUTABLE-NOTFOUND")
 	add_custom_command(OUTPUT ${PROJECT_SOURCE_DIR}/src/bin/basic_lua.h
 					COMMAND ${XXD_EXECUTABLE} -i lua/basic.lua | sed 's/unsigned char/static const unsigned char/g' >basic_lua.h
 					WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}/src/bin/