diff --git a/src/hb-aat-layout-common.hh b/src/hb-aat-layout-common.hh
index 5eaec5e86..1e3a5aba6 100644
--- a/src/hb-aat-layout-common.hh
+++ b/src/hb-aat-layout-common.hh
@@ -790,6 +790,7 @@ struct StateTableDriver
     auto *last_range = ac->range_flags && (ac->range_flags->length > 1) ? &(*ac->range_flags)[0] : nullptr;
     for (buffer->idx = 0; buffer->successful;)
     {
+      /* This block is copied in NoncontextualSubtable::apply. Keep in sync. */
       if (last_range)
       {
 	auto *range = last_range;
diff --git a/src/hb-aat-layout-morx-table.hh b/src/hb-aat-layout-morx-table.hh
index 51003807d..f34470b7b 100644
--- a/src/hb-aat-layout-morx-table.hh
+++ b/src/hb-aat-layout-morx-table.hh
@@ -622,6 +622,7 @@ struct NoncontextualSubtable
     auto *last_range = c->range_flags && (c->range_flags->length > 1) ? &(*c->range_flags)[0] : nullptr;
     for (unsigned int i = 0; i < count; i++)
     {
+      /* This block copied from StateTableDriver::drive. Keep in sync. */
       if (last_range)
       {
 	auto *range = last_range;