$NetBSD$

--- src/SFML/System/CMakeLists.txt.orig	2015-08-24 16:01:06.000000000 +0000
+++ src/SFML/System/CMakeLists.txt
@@ -84,7 +84,7 @@ else()
 endif()
 
 # build the list of external libraries to link
-if(SFML_OS_LINUX OR SFML_OS_FREEBSD OR SFML_OS_MACOSX)
+if(SFML_OS_LINUX OR SFML_OS_FREEBSD OR SFML_OS_NETBSD OR SFML_OS_MACOSX)
     list(APPEND SYSTEM_EXT_LIBS pthread)
 endif()
 if(SFML_OS_LINUX)
