diff --git a/lang/qt/src/qgpgmenewcryptoconfig.cpp b/lang/qt/src/qgpgmenewcryptoconfig.cpp
index eb3af56..af47594 100644
--- a/lang/qt/src/qgpgmenewcryptoconfig.cpp
+++ b/lang/qt/src/qgpgmenewcryptoconfig.cpp
@@ -51,2 +51,3 @@
 #include <cassert>
+#include <functional> /* std::mem_fn */
 
diff --git a/lang/qt/src/threadedjobmixin.h b/lang/qt/src/threadedjobmixin.h
index 32b23db..c4f85c2 100644
--- a/lang/qt/src/threadedjobmixin.h
+++ b/lang/qt/src/threadedjobmixin.h
@@ -53,2 +53,3 @@
 #include <cassert>
+#include <functional> /* std::function */