diff --git a/src/hb-ot-layout-common.hh b/src/hb-ot-layout-common.hh
index b3af128e0..e2e9bcbeb 100644
--- a/src/hb-ot-layout-common.hh
+++ b/src/hb-ot-layout-common.hh
@@ -1937,13 +1937,22 @@ struct ClassDefFormat2_4
     {
       /* Match if there's any glyph that is not listed! */
       hb_codepoint_t g = HB_SET_VALUE_INVALID;
-      for (auto &range : rangeRecord)
+      hb_codepoint_t last = HB_SET_VALUE_INVALID;
+      auto it = hb_iter (rangeRecord);
+      for (auto &range : it)
       {
+        if (it->first == last + 1)
+	{
+	  it++;
+	  continue;
+	}
+
 	if (!glyphs->next (&g))
 	  break;
 	if (g < range.first)
 	  return true;
 	g = range.last;
+	last = g;
       }
       if (g != HB_SET_VALUE_INVALID && glyphs->next (&g))
 	return true;
diff --git a/src/hb-subset-plan.cc b/src/hb-subset-plan.cc
index 9a00de3e6..33ca46d1f 100644
--- a/src/hb-subset-plan.cc
+++ b/src/hb-subset-plan.cc
@@ -605,11 +605,14 @@ _populate_unicodes_to_retain (const hb_set_t *unicodes,
 
     /* Add gids which where requested, but not mapped in cmap */
     unsigned num_glyphs = plan->source->get_num_glyphs ();
-    for (hb_codepoint_t gid : *glyphs)
+    hb_codepoint_t first = HB_SET_VALUE_INVALID, last = HB_SET_VALUE_INVALID;
+    for (; glyphs->next_range (&first, &last); )
     {
-      if (gid >= num_glyphs)
+      if (first >= num_glyphs)
 	break;
-      plan->_glyphset_gsub.add (gid);
+      if (last >= num_glyphs)
+        last = num_glyphs - 1;
+      plan->_glyphset_gsub.add_range (first, last);
     }
   }