diff -up conky-1.10.6/src/luamm.hh.gcc7 conky-1.10.6/src/luamm.hh
--- conky-1.10.6/src/luamm.hh.gcc7	2017-02-20 15:31:45.145623438 +0100
+++ conky-1.10.6/src/luamm.hh	2017-02-20 15:42:02.467168585 +0100
@@ -26,6 +26,7 @@
 #include <memory>
 #include <mutex>
 #include <exception>
+#include <functional>
 #include <stdexcept>
 #include <string>