diff --git a/src/TiledArray/util/bug.h b/src/TiledArray/util/bug.h
index f2f284169a..38ae55198f 100644
--- a/src/TiledArray/util/bug.h
+++ b/src/TiledArray/util/bug.h
@@ -30,6 +30,7 @@
 
 #include <cassert>
 #include <cstdint>
+#include <functional>
 #include <memory>
 #include <string>
 #include <unordered_map>