diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7e102fc5b..fc01ed305 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -130,7 +130,7 @@ else()
         src/Platform_unix.cpp
         )
 
-    set(EXTRA_LIBS pthread)
+    set(EXTRA_LIBS pthread rt)
 endif()
 
 if (CMAKE_SYSTEM_NAME STREQUAL FreeBSD)