diff --git a/src/hb-ot-var-gvar-table.hh b/src/hb-ot-var-gvar-table.hh
index 2cde67d35..316be8b19 100644
--- a/src/hb-ot-var-gvar-table.hh
+++ b/src/hb-ot-var-gvar-table.hh
@@ -646,8 +646,9 @@ struct gvar
 
 	    /* Check the number of unreferenced points in a contour. If no unref points or no ref points, nothing to do. */
 	    unsigned unref_count = 0;
-	    for (unsigned i = start_point; i <= end_point; i++)
-	      unref_count += !deltas.arrayZ[i].flag;
+	    for (unsigned i = start_point; i < end_point + 1; i++)
+	      unref_count += deltas.arrayZ[i].flag;
+	    unref_count = (end_point - start_point + 1) - unref_count;
 
 	    unsigned j = start_point;
 	    if (unref_count == 0 || unref_count > end_point - start_point)