Index: src/modules/sdl/CMakeLists.txt
--- src/modules/sdl/CMakeLists.txt.orig
+++ src/modules/sdl/CMakeLists.txt
@@ -19,6 +19,7 @@ if(APPLE)
   target_link_libraries(mltsdl PRIVATE objc "-framework Foundation")
 elseif(UNIX)
   target_link_libraries(mltsdl PRIVATE X11)
+  target_link_options(mltsdl PRIVATE -Wl,-L/usr/X11R6/lib)
 endif()
 
 set_target_properties(mltsdl PROPERTIES LIBRARY_OUTPUT_DIRECTORY "${MLT_MODULE_OUTPUT_DIRECTORY}")
