diff --git a/src/fileio.c b/src/fileio.c
index e239b5c..9ae69cf 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -3183,7 +3183,7 @@
 	    struct stat	st_new;
 	    char_u	*dirp;
 	    char_u	*rootname;
-#ifndef SHORT_FNAME
+#if defined(UNIX) && !defined(SHORT_FNAME)
 	    int		did_set_shortname;
 #endif
 
@@ -3226,7 +3226,7 @@
 		    goto nobackup;
 		}
 
-#ifndef SHORT_FNAME
+#if defined(UNIX) && !defined(SHORT_FNAME)
 		did_set_shortname = FALSE;
 #endif