diff --git a/CMakeLists.txt b/CMakeLists.txt
index 22e71864..dd256a0f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -12,9 +12,7 @@ endif()
 
 set_property(GLOBAL PROPERTY USE_FOLDERS ON)
 
-if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
-    set(GLFW_STANDALONE TRUE)
-endif()
+string(COMPARE EQUAL ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_SOURCE_DIR} GLFW_STANDALONE)
 
 option(BUILD_SHARED_LIBS "Build shared libraries" OFF)
 option(GLFW_BUILD_EXAMPLES "Build the GLFW example programs" ${GLFW_STANDALONE})