1 files changed, 29 insertions, 13 deletions

diff --git a/thirdparty/harfbuzz/src/OT/Layout/GPOS/PairPosFormat1.hh b/thirdparty/harfbuzz/src/OT/Layout/GPOS/PairPosFormat1.hh
index e4a2006fb9..ac2774a76f 100644
--- a/thirdparty/harfbuzz/src/OT/Layout/GPOS/PairPosFormat1.hh
+++ b/thirdparty/harfbuzz/src/OT/Layout/GPOS/PairPosFormat1.hh
@@ -36,6 +36,7 @@ struct PairPosFormat1_3
     TRACE_SANITIZE (this);
 
     if (!c->check_struct (this)) return_trace (false);
+    hb_barrier ();
 
     unsigned int len1 = valueFormat[0].get_len ();
     unsigned int len2 = valueFormat[1].get_len ();
@@ -131,20 +132,33 @@ struct PairPosFormat1_3
     auto *out = c->serializer->start_embed (*this);
     if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
     out->format = format;
-    out->valueFormat[0] = valueFormat[0];
-    out->valueFormat[1] = valueFormat[1];
-    if (c->plan->flags & HB_SUBSET_FLAGS_NO_HINTING)
+
+    hb_pair_t<unsigned, unsigned> newFormats = hb_pair (valueFormat[0], valueFormat[1]);
+
+    if (c->plan->normalized_coords)
     {
-      hb_pair_t<unsigned, unsigned> newFormats = compute_effective_value_formats (glyphset);
-      out->valueFormat[0] = newFormats.first;
-      out->valueFormat[1] = newFormats.second;
+      /* all device flags will be dropped when full instancing, no need to strip
+       * hints, also do not strip emtpy cause we don't compute the new default
+       * value during stripping */
+      newFormats = compute_effective_value_formats (glyphset, false, false, &c->plan->layout_variation_idx_delta_map);
     }
-
-    if (c->plan->all_axes_pinned)
+    /* do not strip hints for VF */
+    else if (c->plan->flags & HB_SUBSET_FLAGS_NO_HINTING)
     {
-      out->valueFormat[0] = out->valueFormat[0].drop_device_table_flags ();
-      out->valueFormat[1] = out->valueFormat[1].drop_device_table_flags ();
+      hb_blob_t* blob = hb_face_reference_table (c->plan->source, HB_TAG ('f','v','a','r'));
+      bool has_fvar = (blob != hb_blob_get_empty ());
+      hb_blob_destroy (blob);
+
+      bool strip = !has_fvar;
+      /* special case: strip hints when a VF has no GDEF varstore after
+       * subsetting*/
+      if (has_fvar && !c->plan->has_gdef_varstore)
+        strip = true;
+      newFormats = compute_effective_value_formats (glyphset, strip, true);
     }
+    
+    out->valueFormat[0] = newFormats.first;
+    out->valueFormat[1] = newFormats.second;
 
     hb_sorted_vector_t<hb_codepoint_t> new_coverage;
 
@@ -175,7 +189,9 @@ struct PairPosFormat1_3
   }
 
 
-  hb_pair_t<unsigned, unsigned> compute_effective_value_formats (const hb_set_t& glyphset) const
+  hb_pair_t<unsigned, unsigned> compute_effective_value_formats (const hb_set_t& glyphset,
+                                                                 bool strip_hints, bool strip_empty,
+                                                                 const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *varidx_delta_map = nullptr) const
   {
     unsigned record_size = PairSet::get_size (valueFormat);
 
@@ -195,8 +211,8 @@ struct PairPosFormat1_3
       {
         if (record->intersects (glyphset))
         {
-          format1 = format1 | valueFormat[0].get_effective_format (record->get_values_1 ());
-          format2 = format2 | valueFormat[1].get_effective_format (record->get_values_2 (valueFormat[0]));
+          format1 = format1 | valueFormat[0].get_effective_format (record->get_values_1 (), strip_hints, strip_empty, &set, varidx_delta_map);
+          format2 = format2 | valueFormat[1].get_effective_format (record->get_values_2 (valueFormat[0]), strip_hints, strip_empty, &set, varidx_delta_map);
         }
         record = &StructAtOffset<const PairValueRecord> (record, record_size);
       }