diff --git a/src/viewport.cpp b/src/viewport.cpp
index 4fca641f0a..0184438691 100644
--- a/src/viewport.cpp
+++ b/src/viewport.cpp
@@ -102,6 +102,7 @@
 
 #include <map>
 #include <vector>
+#include <math.h>
 
 #include "table/strings.h"
 #include "table/string_colours.h"
diff --git a/src/viewport_type.h b/src/viewport_type.h
index 1bff895aea..5df77a7c12 100644
--- a/src/viewport_type.h
+++ b/src/viewport_type.h
@@ -15,7 +15,6 @@
 #include "zoom_type.h"
 #include "strings_type.h"
 #include "table/strings.h"
-#include "math.h"
 
 class LinkGraphOverlay;