Change hb_void_t implementation

src/hb-dsalgs.hh

@@ -32,8 +32,7 @@
 
 
 /* Void! For when we need a expression-type of void. */
-typedef const struct _hb_void_t *hb_void_t;
-#define HB_VOID ((const _hb_void_t *) nullptr)
+struct hb_void_t { typedef void value; };
 
 
 /*

src/hb-ot-layout-gsub-table.hh

@@ -1380,7 +1380,7 @@ struct SubstLookup : Lookup
   static hb_closure_context_t::return_t dispatch_closure_recurse_func (hb_closure_context_t *c, unsigned int lookup_index)
   {
     if (!c->should_visit_lookup (lookup_index))
-      return HB_VOID;
+      return hb_void_t ();
 
     hb_closure_context_t::return_t ret = dispatch_recurse_func (c, lookup_index);
 

src/hb-ot-layout-gsubgpos.hh

@@ -64,8 +64,8 @@ struct hb_closure_context_t :
   const char *get_name () { return "CLOSURE"; }
   typedef return_t (*recurse_func_t) (hb_closure_context_t *c, unsigned int lookup_index);
   template <typename T>
-  return_t dispatch (const T &obj) { obj.closure (this); return HB_VOID; }
-  static return_t default_return_value () { return HB_VOID; }
+  return_t dispatch (const T &obj) { obj.closure (this); return hb_void_t (); }
+  static return_t default_return_value () { return hb_void_t (); }
   void recurse (unsigned int lookup_index)
   {
     if (unlikely (nesting_level_left == 0 || !recurse_func))
@@ -156,8 +156,8 @@ struct hb_collect_glyphs_context_t :
   const char *get_name () { return "COLLECT_GLYPHS"; }
   typedef return_t (*recurse_func_t) (hb_collect_glyphs_context_t *c, unsigned int lookup_index);
   template <typename T>
-  return_t dispatch (const T &obj) { obj.collect_glyphs (this); return HB_VOID; }
-  static return_t default_return_value () { return HB_VOID; }
+  return_t dispatch (const T &obj) { obj.collect_glyphs (this); return hb_void_t (); }
+  static return_t default_return_value () { return hb_void_t (); }
   void recurse (unsigned int lookup_index)
   {
     if (unlikely (nesting_level_left == 0 || !recurse_func))
@@ -652,9 +652,9 @@ struct hb_get_subtables_context_t :
   {
     hb_applicable_t *entry = array.push();
     entry->init (obj, apply_to<T>);
-    return HB_VOID;
+    return hb_void_t ();
   }
-  static return_t default_return_value () { return HB_VOID; }
+  static return_t default_return_value () { return hb_void_t (); }
 
   hb_get_subtables_context_t (array_t &array_) :
 			      array (array_),