.

wcfs/wcfs.go

@@ -1382,7 +1382,8 @@ func (wlink *WatchLink) setupWatch(ctx context.Context, foid zodb.Oid, at zodb.T
 	// XXX locking
 
 	// pin all tracked file blocks that were changed (at, head] range
-	for _, δfile := range f.δtail.SliceByRev(at, head.zconn.At()) {
+	fhead := tidmin(f.δtail.Head(), head.zconn.At())
+	for _, δfile := range f.δtail.SliceByRev(at, fhead) {
 		for _, blk := range δfile.Changev {
 			_, already := toPin[blk]
 			if already {