=== modified file 'common.zsh'
--- common.zsh	2017-11-30 18:51:45 +0000
+++ common.zsh	2017-11-30 18:37:09 +0000
@@ -20,7 +20,7 @@
 	fpath=( $FUNCDIR $fpath )
 	for f in $FUNCDIR/*(.); do
 		[[ $f:t =~ '^[-_[:alnum:]]*$' ]] || continue
-		functions[$f:t]='ifchange $FUNCDIR/'$f:t' && autoload -UXz'
+		functions[$f:t]='redo-ifchange $FUNCDIR/'$f:t' && autoload -UXz'
 	done
 }
 
@@ -85,6 +85,7 @@
 ifchange() {
 	local arg
 	redo-ifchange "$@"
+	(($+vars[__deps__])) || vars[__deps__]=''
 	for arg in "$@"; do
 		vars[__deps__]+=$(filehash $arg)
 	done
@@ -175,8 +176,6 @@
 	redo-ifchange common.zsh || exit $?
 	autoload_functions
 	decode_args
-	vars[__deps__]=$(filehash $DO)
-	vars[__deps__]+=$(filehash common.zsh)
 	main || exit $?
 	finish
 fi