diff --git a/src/hb-cff2-interp-cs.hh b/src/hb-cff2-interp-cs.hh
index 64c10550e..346d4c1a7 100644
--- a/src/hb-cff2-interp-cs.hh
+++ b/src/hb-cff2-interp-cs.hh
@@ -56,7 +56,7 @@ struct blend_arg_t : number_t
   void reset_blends ()
   {
     numValues = valueIndex = 0;
-    deltas.resize (0);
+    deltas.shrink (0);
   }
 
   unsigned int numValues;