diff --git a/src/utilities.cc b/src/utilities.cc
index 4a935b27..8b5af4d3 100644
--- a/src/utilities.cc
+++ b/src/utilities.cc
@@ -1,3 +1,4 @@
+#include <cmath>
 #include <node.h>
 #include <vips/vips.h>