diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index d594ded36b34e..61359d33d484e 100644
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-0ba4563a4b0dec4c01b90d7b3c9e2ce2cd58a96f
+ea73a80a6047f477d92fccc7de143a3ee1021c65
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
diff --git a/gcc/go/gofrontend/export.cc b/gcc/go/gofrontend/export.cc
index bec4c7ff978e1..6e085991a23ad 100644
--- a/gcc/go/gofrontend/export.cc
+++ b/gcc/go/gofrontend/export.cc
@@ -608,6 +608,9 @@ Export::write_type(const Type* type)
       // definition of the type may refer to the named type via a
       // pointer.
       this->type_refs_[type] = index;
+
+      if (named_type != NULL && named_type->is_alias())
+	this->write_c_string("= ");
     }
 
   type->export_type(this);
diff --git a/gcc/go/gofrontend/gogo.cc b/gcc/go/gofrontend/gogo.cc
index 34346a76a0f65..ad2541c6eee9a 100644
--- a/gcc/go/gofrontend/gogo.cc
+++ b/gcc/go/gofrontend/gogo.cc
@@ -108,12 +108,14 @@ Gogo::Gogo(Backend* backend, Linemap* linemap, int, int pointer_size)
   uint8_type->integer_type()->set_is_byte();
   Named_object* byte_type = Named_object::make_type("byte", NULL, uint8_type,
 						    loc);
+  byte_type->type_value()->set_is_alias();
   this->add_named_type(byte_type->type_value());
 
   // "rune" is an alias for "int32".
   int32_type->integer_type()->set_is_rune();
   Named_object* rune_type = Named_object::make_type("rune", NULL, int32_type,
 						    loc);
+  rune_type->type_value()->set_is_alias();
   this->add_named_type(rune_type->type_value());
 
   this->add_named_type(Type::make_named_bool_type());
@@ -1775,6 +1777,10 @@ Gogo::start_function(const std::string& name, Function_type* type,
 	  if (rtype->classification() == Type::TYPE_POINTER)
 	    rtype = rtype->points_to();
 
+	  while (rtype->named_type() != NULL
+		 && rtype->named_type()->is_alias())
+	    rtype = rtype->named_type()->real_type();
+
 	  if (rtype->is_error_type())
 	    ret = Named_object::make_function(name, NULL, function);
 	  else if (rtype->named_type() != NULL)
@@ -6865,7 +6871,7 @@ Type_declaration::add_method_declaration(const std::string&  name,
   return ret;
 }
 
-// Return whether any methods ere defined.
+// Return whether any methods are defined.
 
 bool
 Type_declaration::has_methods() const
@@ -6878,6 +6884,36 @@ Type_declaration::has_methods() const
 void
 Type_declaration::define_methods(Named_type* nt)
 {
+  if (this->methods_.empty())
+    return;
+
+  while (nt->is_alias())
+    {
+      Type *t = nt->real_type()->forwarded();
+      if (t->named_type() != NULL)
+	nt = t->named_type();
+      else if (t->forward_declaration_type() != NULL)
+	{
+	  Named_object* no = t->forward_declaration_type()->named_object();
+	  Type_declaration* td = no->type_declaration_value();
+	  td->methods_.insert(td->methods_.end(), this->methods_.begin(),
+			      this->methods_.end());
+	  this->methods_.clear();
+	  return;
+	}
+      else
+	{
+	  for (std::vector<Named_object*>::const_iterator p =
+		 this->methods_.begin();
+	       p != this->methods_.end();
+	       ++p)
+	    go_error_at((*p)->location(),
+			("invalid receiver type "
+			 "(receiver must be a named type"));
+	  return;
+	}
+    }
+
   for (std::vector<Named_object*>::const_iterator p = this->methods_.begin();
        p != this->methods_.end();
        ++p)
diff --git a/gcc/go/gofrontend/import.cc b/gcc/go/gofrontend/import.cc
index 2694cea479730..f6b4e0c0566a3 100644
--- a/gcc/go/gofrontend/import.cc
+++ b/gcc/go/gofrontend/import.cc
@@ -737,6 +737,13 @@ Import::read_type()
 
   this->require_c_string(" ");
 
+  bool is_alias = false;
+  if (this->match_c_string("= "))
+    {
+      stream->advance(2);
+      is_alias = true;
+    }
+
   // The package name may follow.  This is the name of the package in
   // the package clause of that package.  The type name will include
   // the pkgpath, which may be different.
@@ -810,6 +817,9 @@ Import::read_type()
 	  // This type has not yet been imported.
 	  ntype->clear_is_visible();
 
+	  if (is_alias)
+	    ntype->set_is_alias();
+
 	  if (!type->is_undefined() && type->interface_type() != NULL)
 	    this->gogo_->record_interface_type(type->interface_type());
 
diff --git a/gcc/go/gofrontend/parse.cc b/gcc/go/gofrontend/parse.cc
index 34a7765418db9..84840fb79c17c 100644
--- a/gcc/go/gofrontend/parse.cc
+++ b/gcc/go/gofrontend/parse.cc
@@ -1515,7 +1515,7 @@ Parse::type_decl()
   this->decl(&Parse::type_spec, NULL);
 }
 
-// TypeSpec = identifier Type .
+// TypeSpec = identifier ["="] Type .
 
 void
 Parse::type_spec(void*)
@@ -1531,6 +1531,13 @@ Parse::type_spec(void*)
   Location location = token->location();
   token = this->advance_token();
 
+  bool is_alias = false;
+  if (token->is_op(OPERATOR_EQ))
+    {
+      is_alias = true;
+      token = this->advance_token();
+    }
+
   // The scope of the type name starts at the point where the
   // identifier appears in the source code.  We implement this by
   // declaring the type before we read the type definition.
@@ -1542,13 +1549,13 @@ Parse::type_spec(void*)
     }
 
   Type* type;
-  if (name == "_" && this->peek_token()->is_keyword(KEYWORD_INTERFACE))
+  if (name == "_" && token->is_keyword(KEYWORD_INTERFACE))
     {
       // We call Parse::interface_type explicity here because we do not want
       // to record an interface with a blank type name.
       type = this->interface_type(false);
     }
-  else if (!this->peek_token()->is_op(OPERATOR_SEMICOLON))
+  else if (!token->is_op(OPERATOR_SEMICOLON))
     type = this->type();
   else
     {
@@ -1579,9 +1586,11 @@ Parse::type_spec(void*)
 	      type = Type::make_error_type();
 	    }
 
-	  this->gogo_->define_type(named_type,
-				   Type::make_named_type(named_type, type,
-							 location));
+	  Named_type* nt = Type::make_named_type(named_type, type, location);
+	  if (is_alias)
+	    nt->set_is_alias();
+
+	  this->gogo_->define_type(named_type, nt);
 	  go_assert(named_type->package() == NULL);
 	}
       else
diff --git a/gcc/go/gofrontend/types.cc b/gcc/go/gofrontend/types.cc
index 0d14adf65b5f6..296e8e51ee0f9 100644
--- a/gcc/go/gofrontend/types.cc
+++ b/gcc/go/gofrontend/types.cc
@@ -328,10 +328,10 @@ Type::are_identical(const Type* t1, const Type* t2, bool errors_are_identical,
   t2 = t2->forwarded();
 
   // Ignore aliases for purposes of type identity.
-  if (t1->named_type() != NULL && t1->named_type()->is_alias())
-    t1 = t1->named_type()->real_type();
-  if (t2->named_type() != NULL && t2->named_type()->is_alias())
-    t2 = t2->named_type()->real_type();
+  while (t1->named_type() != NULL && t1->named_type()->is_alias())
+    t1 = t1->named_type()->real_type()->forwarded();
+  while (t2->named_type() != NULL && t2->named_type()->is_alias())
+    t2 = t2->named_type()->real_type()->forwarded();
 
   if (t1 == t2)
     return true;
@@ -822,6 +822,8 @@ Type::are_convertible(const Type* lhs, const Type* rhs, std::string* reason)
 unsigned int
 Type::hash_for_method(Gogo* gogo) const
 {
+  if (this->named_type() != NULL && this->named_type()->is_alias())
+    return this->named_type()->real_type()->hash_for_method(gogo);
   unsigned int ret = 0;
   if (this->classification_ != TYPE_FORWARD)
     ret += this->classification_;
@@ -1165,8 +1167,8 @@ Bexpression*
 Type::type_descriptor_pointer(Gogo* gogo, Location location)
 {
   Type* t = this->forwarded();
-  if (t->named_type() != NULL && t->named_type()->is_alias())
-    t = t->named_type()->real_type();
+  while (t->named_type() != NULL && t->named_type()->is_alias())
+    t = t->named_type()->real_type()->forwarded();
   if (t->type_descriptor_var_ == NULL)
     {
       t->make_type_descriptor_var(gogo);
@@ -1585,6 +1587,9 @@ Type::make_type_descriptor_ptr_type()
 bool
 Type::needs_specific_type_functions(Gogo* gogo)
 {
+  Named_type* nt = this->named_type();
+  if (nt != NULL && nt->is_alias())
+    return false;
   if (!this->is_comparable())
     return false;
   if (!this->compare_is_identity(gogo))
@@ -1593,7 +1598,6 @@ Type::needs_specific_type_functions(Gogo* gogo)
   // We create a few predeclared types for type descriptors; they are
   // really just for the backend and don't need hash or equality
   // functions.
-  Named_type* nt = this->named_type();
   if (nt != NULL && Linemap::is_predeclared_location(nt->location()))
     return false;
 
@@ -1634,6 +1638,11 @@ Type::type_functions(Gogo* gogo, Named_type* name, Function_type* hash_fntype,
 		     Function_type* equal_fntype, Named_object** hash_fn,
 		     Named_object** equal_fn)
 {
+  // If this loop leaves NAME as NULL, then the type does not have a
+  // name after all.
+  while (name != NULL && name->is_alias())
+    name = name->real_type()->named_type();
+
   if (!this->is_comparable())
     {
       *hash_fn = NULL;
@@ -2164,6 +2173,11 @@ Type::write_named_hash(Gogo* gogo, Named_type* name,
   Location bloc = Linemap::predeclared_location();
 
   Named_type* base_type = name->real_type()->named_type();
+  while (base_type->is_alias())
+    {
+      base_type = base_type->real_type()->named_type();
+      go_assert(base_type != NULL);
+    }
   go_assert(base_type != NULL);
 
   // The pointer to the type we are going to hash.  This is an
@@ -2371,8 +2385,8 @@ Bexpression*
 Type::gc_symbol_pointer(Gogo* gogo)
 {
   Type* t = this->forwarded();
-  if (t->named_type() != NULL && t->named_type()->is_alias())
-    t = t->named_type()->real_type();
+  while (t->named_type() != NULL && t->named_type()->is_alias())
+    t = t->named_type()->real_type()->forwarded();
   if (t->gc_symbol_var_ == NULL)
     {
       t->make_gc_symbol_var(gogo);
@@ -4857,7 +4871,10 @@ Struct_field::field_name() const
       if (dt->forward_declaration_type() != NULL)
 	return dt->forward_declaration_type()->name();
       else if (dt->named_type() != NULL)
-	return dt->named_type()->name();
+	{
+	  // Note that this can be an alias name.
+	  return dt->named_type()->name();
+	}
       else if (t->is_error_type() || dt->is_error_type())
 	{
 	  static const std::string error_string = "*error*";
@@ -5786,7 +5803,12 @@ Struct_type::do_reflection(Gogo* gogo, std::string* ret) const
       else
 	ret->append(Gogo::unpack_hidden_name(p->field_name()));
       ret->push_back(' ');
-      this->append_reflection(p->type(), gogo, ret);
+      if (p->is_anonymous()
+	  && p->type()->named_type() != NULL
+	  && p->type()->named_type()->is_alias())
+	p->type()->named_type()->append_reflection_type_name(gogo, true, ret);
+      else
+	this->append_reflection(p->type(), gogo, ret);
 
       if (p->has_tag())
 	{
@@ -5866,7 +5888,15 @@ Struct_type::do_mangled_name(Gogo* gogo, std::string* ret) const
 	      ret->append(buf);
 	      ret->append(n);
 	    }
-	  this->append_mangled_name(p->type(), gogo, ret);
+
+	  // For an anonymous field with an alias type, the field name
+	  // is the alias name.
+	  if (p->is_anonymous()
+	      && p->type()->named_type() != NULL
+	      && p->type()->named_type()->is_alias())
+	    p->type()->named_type()->append_mangled_type_name(gogo, true, ret);
+	  else
+	    this->append_mangled_name(p->type(), gogo, ret);
 	  if (p->has_tag())
 	    {
 	      const std::string& tag(p->tag());
@@ -9313,18 +9343,6 @@ Named_type::message_name() const
   return this->named_object_->message_name();
 }
 
-// Whether this is an alias.  There are currently only two aliases so
-// we just recognize them by name.
-
-bool
-Named_type::is_alias() const
-{
-  if (!this->is_builtin())
-    return false;
-  const std::string& name(this->name());
-  return name == "byte" || name == "rune";
-}
-
 // Return the base type for this type.  We have to be careful about
 // circular type definitions, which are invalid but may be seen here.
 
@@ -9384,6 +9402,7 @@ Named_type::named_type_is_comparable(std::string* reason) const
 Named_object*
 Named_type::add_method(const std::string& name, Function* function)
 {
+  go_assert(!this->is_alias_);
   if (this->local_methods_ == NULL)
     this->local_methods_ = new Bindings(NULL);
   return this->local_methods_->add_function(name, NULL, function);
@@ -9396,6 +9415,7 @@ Named_type::add_method_declaration(const std::string& name, Package* package,
 				   Function_type* type,
 				   Location location)
 {
+  go_assert(!this->is_alias_);
   if (this->local_methods_ == NULL)
     this->local_methods_ = new Bindings(NULL);
   return this->local_methods_->add_function_declaration(name, package, type,
@@ -9407,6 +9427,7 @@ Named_type::add_method_declaration(const std::string& name, Package* package,
 void
 Named_type::add_existing_method(Named_object* no)
 {
+  go_assert(!this->is_alias_);
   if (this->local_methods_ == NULL)
     this->local_methods_ = new Bindings(NULL);
   this->local_methods_->add_named_object(no);
@@ -9418,11 +9439,51 @@ Named_type::add_existing_method(Named_object* no)
 Named_object*
 Named_type::find_local_method(const std::string& name) const
 {
+  if (this->is_error_)
+    return NULL;
+  if (this->is_alias_)
+    {
+      Named_type* nt = this->type_->named_type();
+      if (nt != NULL)
+	{
+	  if (this->seen_alias_)
+	    return NULL;
+	  this->seen_alias_ = true;
+	  Named_object* ret = nt->find_local_method(name);
+	  this->seen_alias_ = false;
+	  return ret;
+	}
+      return NULL;
+    }
   if (this->local_methods_ == NULL)
     return NULL;
   return this->local_methods_->lookup(name);
 }
 
+// Return the list of local methods.
+
+const Bindings*
+Named_type::local_methods() const
+{
+  if (this->is_error_)
+    return NULL;
+  if (this->is_alias_)
+    {
+      Named_type* nt = this->type_->named_type();
+      if (nt != NULL)
+	{
+	  if (this->seen_alias_)
+	    return NULL;
+	  this->seen_alias_ = true;
+	  const Bindings* ret = nt->local_methods();
+	  this->seen_alias_ = false;
+	  return ret;
+	}
+      return NULL;
+    }
+  return this->local_methods_;
+}
+
 // Return whether NAME is an unexported field or method, for better
 // error reporting.
 
@@ -9430,6 +9491,22 @@ bool
 Named_type::is_unexported_local_method(Gogo* gogo,
 				       const std::string& name) const
 {
+  if (this->is_error_)
+    return false;
+  if (this->is_alias_)
+    {
+      Named_type* nt = this->type_->named_type();
+      if (nt != NULL)
+	{
+	  if (this->seen_alias_)
+	    return false;
+	  this->seen_alias_ = true;
+	  bool ret = nt->is_unexported_local_method(gogo, name);
+	  this->seen_alias_ = false;
+	  return ret;
+	}
+      return false;
+    }
   Bindings* methods = this->local_methods_;
   if (methods != NULL)
     {
@@ -9454,6 +9531,8 @@ Named_type::is_unexported_local_method(Gogo* gogo,
 void
 Named_type::finalize_methods(Gogo* gogo)
 {
+  if (this->is_alias_)
+    return;
   if (this->all_methods_ != NULL)
     return;
 
@@ -9474,6 +9553,56 @@ Named_type::finalize_methods(Gogo* gogo)
   Type::finalize_methods(gogo, this, this->location_, &this->all_methods_);
 }
 
+// Return whether this type has any methods.
+
+bool
+Named_type::has_any_methods() const
+{
+  if (this->is_error_)
+    return false;
+  if (this->is_alias_)
+    {
+      if (this->type_->named_type() != NULL)
+	{
+	  if (this->seen_alias_)
+	    return false;
+	  this->seen_alias_ = true;
+	  bool ret = this->type_->named_type()->has_any_methods();
+	  this->seen_alias_ = false;
+	  return ret;
+	}
+      if (this->type_->struct_type() != NULL)
+	return this->type_->struct_type()->has_any_methods();
+      return false;
+    }
+  return this->all_methods_ != NULL;
+}
+
+// Return the methods for this type.
+
+const Methods*
+Named_type::methods() const
+{
+  if (this->is_error_)
+    return NULL;
+  if (this->is_alias_)
+    {
+      if (this->type_->named_type() != NULL)
+	{
+	  if (this->seen_alias_)
+	    return NULL;
+	  this->seen_alias_ = true;
+	  const Methods* ret = this->type_->named_type()->methods();
+	  this->seen_alias_ = false;
+	  return ret;
+	}
+      if (this->type_->struct_type() != NULL)
+	return this->type_->struct_type()->methods();
+      return NULL;
+    }
+  return this->all_methods_;
+}
+
 // Return the method NAME, or NULL if there isn't one or if it is
 // ambiguous.  Set *IS_AMBIGUOUS if the method exists but is
 // ambiguous.
@@ -9481,6 +9610,26 @@ Named_type::finalize_methods(Gogo* gogo)
 Method*
 Named_type::method_function(const std::string& name, bool* is_ambiguous) const
 {
+  if (this->is_error_)
+    return NULL;
+  if (this->is_alias_)
+    {
+      if (is_ambiguous != NULL)
+	*is_ambiguous = false;
+      if (this->type_->named_type() != NULL)
+	{
+	  if (this->seen_alias_)
+	    return NULL;
+	  this->seen_alias_ = true;
+	  Named_type* nt = this->type_->named_type();
+	  Method* ret = nt->method_function(name, is_ambiguous);
+	  this->seen_alias_ = false;
+	  return ret;
+	}
+      if (this->type_->struct_type() != NULL)
+	return this->type_->struct_type()->method_function(name, is_ambiguous);
+      return NULL;
+    }
   return Type::method_function(this->all_methods_, name, is_ambiguous);
 }
 
@@ -9491,6 +9640,25 @@ Named_type::method_function(const std::string& name, bool* is_ambiguous) const
 Expression*
 Named_type::interface_method_table(Interface_type* interface, bool is_pointer)
 {
+  if (this->is_error_)
+    return Expression::make_error(this->location_);
+  if (this->is_alias_)
+    {
+      if (this->type_->named_type() != NULL)
+	{
+	  if (this->seen_alias_)
+	    return Expression::make_error(this->location_);
+	  this->seen_alias_ = true;
+	  Named_type* nt = this->type_->named_type();
+	  Expression* ret = nt->interface_method_table(interface, is_pointer);
+	  this->seen_alias_ = false;
+	  return ret;
+	}
+      if (this->type_->struct_type() != NULL)
+	return this->type_->struct_type()->interface_method_table(interface,
+								  is_pointer);
+      go_unreachable();
+    }
   return Type::interface_method_table(this, interface, is_pointer,
                                       &this->interface_method_tables_,
                                       &this->pointer_interface_method_tables_);
@@ -9609,6 +9777,55 @@ Find_type_use::type(Type* type)
   return TRAVERSE_CONTINUE;
 }
 
+// Look for a circular reference of an alias.
+
+class Find_alias : public Traverse
+{
+ public:
+  Find_alias(Named_type* find_type)
+    : Traverse(traverse_types),
+      find_type_(find_type), found_(false)
+  { }
+
+  // Whether we found the type.
+  bool
+  found() const
+  { return this->found_; }
+
+ protected:
+  int
+  type(Type*);
+
+ private:
+  // The type we are looking for.
+  Named_type* find_type_;
+  // Whether we found the type.
+  bool found_;
+};
+
+int
+Find_alias::type(Type* type)
+{
+  Named_type* nt = type->named_type();
+  if (nt != NULL)
+    {
+      if (nt == this->find_type_)
+	{
+	  this->found_ = true;
+	  return TRAVERSE_EXIT;
+	}
+
+      // We started from `type T1 = T2`, where T1 is find_type_ and T2
+      // is, perhaps indirectly, the parameter TYPE.  If TYPE is not
+      // an alias itself, it's OK if whatever T2 is defined as refers
+      // to T1.
+      if (!nt->is_alias())
+	return TRAVERSE_SKIP_COMPONENTS;
+    }
+
+  return TRAVERSE_CONTINUE;
+}
+
 // Verify that a named type does not refer to itself.
 
 bool
@@ -9618,6 +9835,22 @@ Named_type::do_verify()
     return true;
   this->is_verified_ = true;
 
+  if (this->is_error_)
+    return false;
+
+  if (this->is_alias_)
+    {
+      Find_alias find(this);
+      Type::traverse(this->type_, &find);
+      if (find.found())
+	{
+	  go_error_at(this->location_, "invalid recursive alias %qs",
+		      this->message_name().c_str());
+	  this->is_error_ = true;
+	  return false;
+	}
+    }
+
   Find_type_use find(this);
   Type::traverse(this->type_, &find);
   if (find.found())
@@ -9718,8 +9951,11 @@ Named_type::do_needs_key_update()
 unsigned int
 Named_type::do_hash_for_method(Gogo* gogo) const
 {
-  if (this->is_alias())
-    return this->type_->named_type()->do_hash_for_method(gogo);
+  if (this->is_error_)
+    return 0;
+
+  // Aliases are handled in Type::hash_for_method.
+  go_assert(!this->is_alias_);
 
   const std::string& name(this->named_object()->name());
   unsigned int ret = Type::hash_string(name, 0);
@@ -10089,8 +10325,17 @@ Named_type::do_get_backend(Gogo* gogo)
 Expression*
 Named_type::do_type_descriptor(Gogo* gogo, Named_type* name)
 {
-  if (name == NULL && this->is_alias())
-    return this->type_->type_descriptor(gogo, this->type_);
+  if (this->is_error_)
+    return Expression::make_error(this->location_);
+  if (name == NULL && this->is_alias_)
+    {
+      if (this->seen_alias_)
+	return Expression::make_error(this->location_);
+      this->seen_alias_ = true;
+      Expression* ret = this->type_->type_descriptor(gogo, NULL);
+      this->seen_alias_ = false;
+      return ret;
+    }
 
   // If NAME is not NULL, then we don't really want the type
   // descriptor for this type; we want the descriptor for the
@@ -10106,9 +10351,25 @@ Named_type::do_type_descriptor(Gogo* gogo, Named_type* name)
 void
 Named_type::do_reflection(Gogo* gogo, std::string* ret) const
 {
-  if (this->is_alias())
+  this->append_reflection_type_name(gogo, false, ret);
+}
+
+// Add to the reflection string.  For an alias we normally use the
+// real name, but if USE_ALIAS is true we use the alias name itself.
+
+void
+Named_type::append_reflection_type_name(Gogo* gogo, bool use_alias,
+					std::string* ret) const
+{
+  if (this->is_error_)
+    return;
+  if (this->is_alias_ && !use_alias)
     {
+      if (this->seen_alias_)
+	return;
+      this->seen_alias_ = true;
       this->append_reflection(this->type_, gogo, ret);
+      this->seen_alias_ = false;
       return;
     }
   if (!this->is_builtin())
@@ -10173,9 +10434,25 @@ Named_type::do_gc_symbol(Gogo* gogo, Expression_list** vals,
 void
 Named_type::do_mangled_name(Gogo* gogo, std::string* ret) const
 {
-  if (this->is_alias())
+  this->append_mangled_type_name(gogo, false, ret);
+}
+
+// Get the mangled name.  For an alias we normally get the real name,
+// but if USE_ALIAS is true we use the alias name itself.
+
+void
+Named_type::append_mangled_type_name(Gogo* gogo, bool use_alias,
+				     std::string* ret) const
+{
+  if (this->is_error_)
+    return;
+  if (this->is_alias_ && !use_alias)
     {
+      if (this->seen_alias_)
+	return;
+      this->seen_alias_ = true;
       this->append_mangled_name(this->type_, gogo, ret);
+      this->seen_alias_ = false;
       return;
     }
   Named_object* no = this->named_object_;
@@ -11392,7 +11669,7 @@ Forward_declaration_type::do_type_descriptor(Gogo* gogo, Named_type* name)
       if (name != NULL)
 	return this->named_type_descriptor(gogo, t, name);
       else
-	return Expression::make_type_descriptor(t, ploc);
+	return Expression::make_error(this->named_object_->location());
     }
 }
 
diff --git a/gcc/go/gofrontend/types.h b/gcc/go/gofrontend/types.h
index e9c31628ec13c..a2a6e611cc8df 100644
--- a/gcc/go/gofrontend/types.h
+++ b/gcc/go/gofrontend/types.h
@@ -3061,10 +3061,10 @@ class Named_type : public Type
       type_(type), local_methods_(NULL), all_methods_(NULL),
       interface_method_tables_(NULL), pointer_interface_method_tables_(NULL),
       location_(location), named_btype_(NULL), dependencies_(),
-      is_visible_(true), is_error_(false), is_placeholder_(false),
-      is_converted_(false), is_circular_(false), is_verified_(false),
-      seen_(false), seen_in_compare_is_identity_(false),
-      seen_in_get_backend_(false)
+      is_alias_(false), is_visible_(true), is_error_(false),
+      is_placeholder_(false), is_converted_(false), is_circular_(false),
+      is_verified_(false), seen_(false), seen_in_compare_is_identity_(false),
+      seen_in_get_backend_(false), seen_alias_(false)
   { }
 
   // Return the associated Named_object.  This holds the actual name.
@@ -3082,6 +3082,17 @@ class Named_type : public Type
   set_named_object(Named_object* no)
   { this->named_object_ = no; }
 
+  // Whether this is an alias (type T1 = T2) rather than an ordinary
+  // named type (type T1 T2).
+  bool
+  is_alias() const
+  { return this->is_alias_; }
+
+  // Record that this type is an alias.
+  void
+  set_is_alias()
+  { this->is_alias_ = true; }
+
   // Return the function in which this type is defined.  This will
   // return NULL for a type defined in global scope.
   const Named_object*
@@ -3143,11 +3154,6 @@ class Named_type : public Type
   is_builtin() const
   { return Linemap::is_predeclared_location(this->location_); }
 
-  // Whether this is an alias.  There are currently two aliases: byte
-  // and rune.
-  bool
-  is_alias() const;
-
   // Whether this named type is valid.  A recursive named type is invalid.
   bool
   is_valid() const
@@ -3195,8 +3201,7 @@ class Named_type : public Type
 
   // Return the list of local methods.
   const Bindings*
-  local_methods() const
-  { return this->local_methods_; }
+  local_methods() const;
 
   // Build the complete list of methods, including those from
   // anonymous fields, and build method stubs if needed.
@@ -3206,14 +3211,12 @@ class Named_type : public Type
   // Return whether this type has any methods.  This should only be
   // called after the finalize_methods pass.
   bool
-  has_any_methods() const
-  { return this->all_methods_ != NULL; }
+  has_any_methods() const;
 
   // Return the methods for this type.  This should only be called
   // after the finalized_methods pass.
   const Methods*
-  methods() const
-  { return this->all_methods_; }
+  methods() const;
 
   // Return the method to use for NAME.  This returns NULL if there is
   // no such method or if the method is ambiguous.  When it returns
@@ -3246,6 +3249,16 @@ class Named_type : public Type
   is_named_backend_type_size_known() const
   { return this->named_btype_ != NULL && !this->is_placeholder_; }
 
+  // Add to the reflection string as for Type::append_reflection, but
+  // if USE_ALIAS use the alias name rather than the alias target.
+  void
+  append_reflection_type_name(Gogo*, bool use_alias, std::string*) const;
+
+  // Append the mangled type name as for Type::append_mangled_name,
+  // but if USE_ALIAS use the alias name rather than the alias target.
+  void
+  append_mangled_type_name(Gogo*, bool use_alias, std::string*) const;
+
   // Export the type.
   void
   export_named_type(Export*, const std::string& name) const;
@@ -3340,6 +3353,8 @@ class Named_type : public Type
   // where we can't convert S2 to the backend representation unless we
   // have converted S1.
   std::vector<Named_type*> dependencies_;
+  // Whether this is an alias type.
+  bool is_alias_;
   // Whether this type is visible.  This is false if this type was
   // created because it was referenced by an imported object, but the
   // type itself was not exported.  This will always be true for types
@@ -3367,6 +3382,8 @@ class Named_type : public Type
   bool seen_in_compare_is_identity_;
   // Like seen_, but used only by do_get_backend.
   bool seen_in_get_backend_;
+  // Like seen_, but used when resolving aliases.
+  mutable bool seen_alias_;
 };
 
 // A forward declaration.  This handles a type which has been declared