Thinko.

Makefile.maint

@@ -77,12 +77,13 @@ cvs-tag-check:
 	else :; fi
 
 cvs-diff-check:
-	if cvs diff | grep -v '^?' >cvs-diffs; then	  	\
-	  rm cvs-diffs;					  	\
-	else						  	\
+	cvs diff | grep -v '^?' >cvs-diffs
+	if grep . cvs-diff >dev/null; then	  		\
 	  echo "Some files are locally modified:" 1>&2;  	\
 	  cat cvs-diffs;					\
 	  exit 1;						\
+	else						  	\
+	  rm cvs-diffs;					  	\
 	fi
 
 cvs-check: cvs-diff-check cvs-tag-check