diff --git a/src/app/ui/animated_widget.h b/src/app/ui/animated_widget.h
index 01f23918b..00ebca6d8 100644
--- a/src/app/ui/animated_widget.h
+++ b/src/app/ui/animated_widget.h
@@ -12,6 +12,8 @@
 #include "base/connection.h"
 #include "ui/timer.h"
 
+#include <cmath>
+
 namespace app {
 
   class AnimatedWidget {