--- a/mercurial/cext/revlog.c	Sun Nov 03 00:15:12 2019 +0100
+++ b/mercurial/cext/revlog.c	Fri Nov 08 10:01:10 2019 +0100
@@ -2489,7 +2489,7 @@
 		if (self->ntinitialized) {
 			Py_ssize_t i;
 
-			for (i = start + 1; i < self->length; i++) {
+			for (i = start; i < self->length; i++) {
 				const char *node = index_node_existing(self, i);
 				if (node == NULL)
 					return -1;