diff --git a/whisper.cpp b/whisper.cpp
index 8cada57d..8f4fd714 100644
--- a/whisper.cpp
+++ b/whisper.cpp
@@ -29,6 +29,7 @@
 #include <vector>
 #include <regex>
 #include <random>
+#include <functional>
 
 #if defined(_MSC_VER)
 #pragma warning(disable: 4244 4267) // possible loss of data