--- a/crawl-ref/source/ui.orig.cc 2020-03-22 05:52:08.000000000 +0100
+++ b/crawl-ref/source/ui.cc 2020-04-22 14:56:57.938271318 +0200
@@ -30,6 +30,8 @@
# include "view.h"
#endif
+#include <cwctype>
+
#ifdef USE_TILE_WEB
# include <unordered_map>