diff --git a/src/hb-subset-cff2.cc b/src/hb-subset-cff2.cc
index bafd79d83..4f865d6c6 100644
--- a/src/hb-subset-cff2.cc
+++ b/src/hb-subset-cff2.cc
@@ -312,7 +312,7 @@ static inline bool _write_cff2 (const cff2_subset_plan &plan,
     assert (cff2->topDict + plan.offsets.topDictSize == c.head - c.start);
     CFF2Subrs *dest = c.start_embed<CFF2Subrs> ();
     if (unlikely (dest == nullptr)) return false;
-    Index<HBUINT32> *super = dest;
+    CFF::Index<HBUINT32> *super = dest;
     if (unlikely (!super->serialize (&c, *acc.globalSubrs)))
     {
       DEBUG_MSG (SUBSET, nullptr, "failed to serialize CFF2 global subrs");
@@ -409,7 +409,7 @@ static inline bool _write_cff2 (const cff2_subset_plan &plan,
           DEBUG_MSG (SUBSET, nullptr, "CFF2 subset: local subrs unexpectedly null [%d]", i);
           return false;
         }
-        Index<HBUINT32> *super = subrs;
+        CFF::Index<HBUINT32> *super = subrs;
         if (unlikely (!super->serialize (&c, *acc.privateDicts[i].localSubrs)))
         {
           DEBUG_MSG (SUBSET, nullptr, "failed to serialize CFF2 local subrs [%d]", i);