diff --git a/src/hb-aat-layout-common.hh b/src/hb-aat-layout-common.hh
index 3b77463f6..c26f376aa 100644
--- a/src/hb-aat-layout-common.hh
+++ b/src/hb-aat-layout-common.hh
@@ -1009,7 +1009,7 @@ struct StateTableDriver
 
           /* 2c'. */
           if (c->is_actionable (buffer, this, wouldbe_entry))
-              return false;
+	    return false;
 
           /* 2c". */
           return next_state == machine.new_state(wouldbe_entry.newState)
diff --git a/src/hb-aat-layout-morx-table.hh b/src/hb-aat-layout-morx-table.hh
index 7b8dd2585..4a94e6a8f 100644
--- a/src/hb-aat-layout-morx-table.hh
+++ b/src/hb-aat-layout-morx-table.hh
@@ -76,7 +76,7 @@ struct RearrangementSubtable
 
     bool is_actionable (hb_buffer_t *buffer HB_UNUSED,
 			StateTableDriver<Types, EntryData> *driver HB_UNUSED,
-			const Entry<EntryData> &entry)
+			const Entry<EntryData> &entry) const
     {
       return (entry.flags & Verb) && start < end;
     }
@@ -226,7 +226,7 @@ struct ContextualSubtable
 
     bool is_actionable (hb_buffer_t *buffer,
 			StateTableDriver<Types, EntryData> *driver,
-			const Entry<EntryData> &entry)
+			const Entry<EntryData> &entry) const
     {
       if (buffer->idx == buffer->len && !mark_set)
 	return false;
@@ -466,7 +466,7 @@ struct LigatureSubtable
 
     bool is_actionable (hb_buffer_t *buffer HB_UNUSED,
 			StateTableDriver<Types, EntryData> *driver HB_UNUSED,
-			const Entry<EntryData> &entry)
+			const Entry<EntryData> &entry) const
     {
       return LigatureEntryT::performAction (entry);
     }
@@ -757,7 +757,7 @@ struct InsertionSubtable
 
     bool is_actionable (hb_buffer_t *buffer HB_UNUSED,
 			StateTableDriver<Types, EntryData> *driver HB_UNUSED,
-			const Entry<EntryData> &entry)
+			const Entry<EntryData> &entry) const
     {
       return (entry.flags & (CurrentInsertCount | MarkedInsertCount)) &&
 	     (entry.data.currentInsertIndex != 0xFFFF ||entry.data.markedInsertIndex != 0xFFFF);