diff --git a/simgear/canvas/elements/CanvasElement.cxx b/simgear/canvas/elements/CanvasElement.cxx
index 30601e77..49c7a47b 100644
--- a/simgear/canvas/elements/CanvasElement.cxx
+++ b/simgear/canvas/elements/CanvasElement.cxx
@@ -32,6 +32,7 @@
 #include <boost/make_shared.hpp>
 
 #include <cassert>
+#include <cmath>
 #include <cstring>
 
 namespace simgear