diff --git a/CMakeLists.txt b/CMakeLists.txt
index 37ef9c9..03c87a4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -283,11 +283,14 @@ endif()
 if(WIN32)
 	set(OPENSSL_LIBS ${OPENSSL_LIBS} ws2_32)
 endif()
-check_library_exists(rt clock_gettime "time.h" HAVE_CLOCK_GETTIME)
-if (HAVE_CLOCK_GETTIME)
+
+check_function_exists(clock_gettime HAVE_CLOCK_GETTIME)
+if(HAVE_CLOCK_GETTIME)
 	add_definitions(-DHAVE_CLOCK_GETTIME)
 endif()
+
 if(CMAKE_SYSTEM_NAME MATCHES "Linux")
+	check_library_exists(rt clock_gettime "time.h" HAVE_CLOCK_GETTIME)
 	if (HAVE_CLOCK_GETTIME)
 		set(OPENSSL_LIBS ${OPENSSL_LIBS} rt)
 	endif()