--- a/src/callbacks.c
+++ b/src/callbacks.c
@@ -47,6 +47,7 @@
 #include "client.h"
 #include "landvalue.h"
 #include "gtkhelp_reports.h"
+#include "support.h"
 
 #include "sdlwin.h"
 #include "utils.h"
--- a/src/gtkhelp_reports.c
+++ b/src/gtkhelp_reports.c
@@ -5,6 +5,7 @@
 #include "player.h"
 #include "client.h"
 #include "gtkhelp_reports.h"
+#include "support.h"
 
 /**** HELPERS ****/
 
--- a/src/gtkhelp_reports.h
+++ b/src/gtkhelp_reports.h
@@ -17,4 +17,6 @@ extern void update_population_report(GtkWidget *window, client_t *client);
 extern void setup_info_treeview(GtkWidget *window);
 extern void update_info_report(GtkWidget *window, client_t *client, int mapx, int mapy);
 
+extern void update_info_window(GtkWidget *window, client_t *client, int mapx, int mapy);
+
 #endif /* GTKHELP_REPORTS */