diff --git a/src/truetype/ttgload.c b/src/truetype/ttgload.c
index 52f8ea8bc..cca81b41c 100644
--- a/src/truetype/ttgload.c
+++ b/src/truetype/ttgload.c
@@ -453,6 +453,8 @@
       /* and thus allocate the bytecode array size by ourselves     */
       if ( n_ins )
       {
+        if ( exec->glyphSize )
+          FT_FREE( exec->glyphIns );
         if ( FT_QNEW_ARRAY( exec->glyphIns, n_ins ) )
           return error;