patch 7.4.2048
Problem:    There is still code and help for unsupported systems.
Solution:   Remove the code and text. (Hirohito Higashi)
diff --git a/src/undo.c b/src/undo.c
index e60e9fa..71e62a1 100644
--- a/src/undo.c
+++ b/src/undo.c
@@ -641,7 +641,7 @@
 	u_getbot();
     }
 
-#if !defined(UNIX) && !defined(WIN32) && !defined(__EMX__)
+#if !defined(UNIX) && !defined(WIN32)
 	/*
 	 * With Amiga we can't handle big undo's, because
 	 * then u_alloc_line would have to allocate a block larger than 32K