diff --git a/PWire.cc b/PWire.cc
index d9a9899c6..dbe68afcb 100644
--- a/PWire.cc
+++ b/PWire.cc
@@ -33,7 +33,7 @@ PWire::PWire(perm_string n,
 : name_(n), type_(t), port_type_(pt), data_type_(dt),
   signed_(false),
   port_set_(false), net_set_(false), is_scalar_(false),
-  error_cnt_(0), set_data_type_(0), discipline_(0)
+  error_cnt_(0), discipline_(0)
 {
       switch (rt) {
 	  case SR_PORT:
@@ -195,8 +195,11 @@ void PWire::set_unpacked_idx(const list<pform_range_t>&ranges)
 
 void PWire::set_data_type(data_type_t*type)
 {
-      assert(set_data_type_ == 0 || set_data_type_ == type);
-      set_data_type_ = type;
+      if (set_data_type_.get() == type)
+	    return;
+
+      assert(!set_data_type_.get());
+      set_data_type_.reset(type);
 }
 
 void PWire::set_discipline(ivl_discipline_t d)
diff --git a/PWire.h b/PWire.h
index e9565a2d5..1f92fac9e 100644
--- a/PWire.h
+++ b/PWire.h
@@ -123,7 +123,7 @@ class PWire : public PNamedItem {
 
 	// This is the complex type of the wire. the data_type_ may
 	// modify how this is interpreted.
-      data_type_t*set_data_type_;
+      std::unique_ptr<data_type_t> set_data_type_;
 
       ivl_discipline_t discipline_;
 
diff --git a/configure.ac b/configure.ac
index 13585836c..7055f4f32 100644
--- a/configure.ac
+++ b/configure.ac
@@ -104,7 +104,7 @@ AS_IF( [test "x$with_m32" = xyes],
     [])
 
 CFLAGS="$CTARGETFLAGS $CFLAGS"
-CXXFLAGS="$CTARGETFLAGS $CXXFLAGS"
+CXXFLAGS="$CTARGETFLAGS $CXXFLAGS -std=c++11"
 LDFLAGS="$CTARGETFLAGS $LDFLAGS"
 
 # Check that we are using either the GNU compilers or the Sun compilers
diff --git a/elab_scope.cc b/elab_scope.cc
index e798d0c91..a03d4df75 100644
--- a/elab_scope.cc
+++ b/elab_scope.cc
@@ -444,7 +444,7 @@ static void blend_class_constructors(PClass*pclass)
 
 	// If we do not have an explicit constructor chain, but there
 	// is a parent class, then create an implicit chain.
-      if (chain_new==0 && pclass->type->base_type!=0) {
+      if (chain_new==0 && pclass->type->base_type) {
 	    chain_new = new PChainConstructor(pclass->type->base_args);
 	    chain_new->set_line(*pclass);
       }
@@ -512,16 +512,6 @@ static void elaborate_scope_class(Design*des, NetScope*scope, PClass*pclass)
 
       netclass_t*use_class = new netclass_t(use_type->name, use_base_class);
 
-      // If this is a package we need to remember the elaborated type so that
-      // scoped type references work. Since there is only one instance for each
-      // package this works. For classes defined in modules there might be
-      // multiple instances though. Each module instance will have its own class
-      // type instance, so the same does not work there.
-      if (scope->type() == NetScope::PACKAGE) {
-	    ivl_assert(*pclass, use_type->save_elaborated_type == 0);
-	    use_type->save_elaborated_type = use_class;
-      }
-
       NetScope*class_scope = new NetScope(scope, hname_t(pclass->pscope_name()),
 					  NetScope::CLASS, scope->unit());
       class_scope->set_line(pclass);
diff --git a/elab_sig.cc b/elab_sig.cc
index f4e26c5bd..924fdb945 100644
--- a/elab_sig.cc
+++ b/elab_sig.cc
@@ -939,10 +939,10 @@ bool test_ranges_eeq(const vector<netrange_t>&lef, const vector<netrange_t>&rig)
 ivl_type_t PWire::elaborate_type(Design*des, NetScope*scope,
 			         const std::vector<netrange_t>&packed_dimensions) const
 {
-      if (set_data_type_ && !dynamic_cast<vector_type_t*>(set_data_type_)) {
-	    ivl_type_t use_type = set_data_type_->elaborate_type(des, scope);
+      vector_type_t *vec_type = dynamic_cast<vector_type_t*>(set_data_type_.get());
+      if (set_data_type_ && !vec_type) {
 	    ivl_assert(*this, packed_dimensions.empty());
-	    return use_type;
+	    return set_data_type_->elaborate_type(des, scope);
       }
 
       // Fallback method. Create vector type.
@@ -1003,10 +1003,6 @@ NetNet* PWire::elaborate_sig(Design*des, NetScope*scope) const
       unsigned wid = 1;
       vector<netrange_t>packed_dimensions;
 
-      NetScope *type_scope = scope;
-      if (set_data_type_ && !set_data_type_->name.nil())
-            type_scope = type_scope->find_typedef_scope(des, set_data_type_);
-
       des->errors += error_cnt_;
 
       if (port_set_ || net_set_) {
@@ -1046,7 +1042,7 @@ NetNet* PWire::elaborate_sig(Design*des, NetScope*scope) const
 			cerr << get_fileline() << ": PWire::elaborate_sig: "
 			     << "Evaluate ranges for net " << basename() << endl;
 		  }
-		  dimensions_ok &= evaluate_ranges(des, type_scope, this, nlist, net_);
+		  dimensions_ok &= evaluate_ranges(des, scope, this, nlist, net_);
 	    }
             assert(net_set_ || net_.empty());
 
@@ -1147,10 +1143,10 @@ NetNet* PWire::elaborate_sig(Design*des, NetScope*scope) const
 	    wtype = NetNet::WIRE;
       }
 
-      ivl_type_t type = elaborate_type(des, type_scope, packed_dimensions);
+      ivl_type_t type = elaborate_type(des, scope, packed_dimensions);
 	// Create the type for the unpacked dimensions. If the
 	// unpacked_dimensions are empty this will just return the base type.
-      type = elaborate_array_type(des, type_scope, *this, type, unpacked_);
+      type = elaborate_array_type(des, scope, *this, type, unpacked_);
 
       list<netrange_t> unpacked_dimensions;
 	// If this is an unpacked array extract the base type and unpacked
diff --git a/elab_type.cc b/elab_type.cc
index a6be08f69..9c8280c61 100644
--- a/elab_type.cc
+++ b/elab_type.cc
@@ -18,6 +18,7 @@
  */
 
 # include  "PExpr.h"
+# include  "PScope.h"
 # include  "pform_types.h"
 # include  "netlist.h"
 # include  "netclass.h"
@@ -40,10 +41,7 @@ using namespace std;
  */
 ivl_type_t data_type_t::elaborate_type(Design*des, NetScope*scope)
 {
-	// User-defined types must be elaborated in the context
-	// where they were defined.
-      if (!name.nil())
-	    scope = scope->find_typedef_scope(des, this);
+      scope = find_scope(des, scope);
 
       ivl_assert(*this, scope);
       Definitions*use_definitions = scope;
@@ -57,6 +55,11 @@ ivl_type_t data_type_t::elaborate_type(Design*des, NetScope*scope)
       return tmp;
 }
 
+NetScope *data_type_t::find_scope(Design *, NetScope *scope) const
+{
+	return scope;
+}
+
 ivl_type_t data_type_t::elaborate_type_raw(Design*des, NetScope*) const
 {
       cerr << get_fileline() << ": internal error: "
@@ -112,8 +115,6 @@ ivl_type_t atom_type_t::elaborate_type_raw(Design*des, NetScope*) const
 
 ivl_type_t class_type_t::elaborate_type_raw(Design*des, NetScope*scope) const
 {
-      if (save_elaborated_type)
-	    return save_elaborated_type;
       return scope->find_class(des, name);
 }
 
@@ -366,3 +367,26 @@ ivl_type_t uarray_type_t::elaborate_type_raw(Design*des, NetScope*scope) const
 
       return elaborate_array_type(des, scope, *this, btype, *dims.get());
 }
+
+ivl_type_t typeref_t::elaborate_type_raw(Design*des, NetScope*s) const
+{
+      if (!s) {
+	    // Try to recover
+	    return new netvector_t(IVL_VT_LOGIC);
+      }
+
+      return type->elaborate_type(des, s);
+}
+
+NetScope *typeref_t::find_scope(Design *des, NetScope *s) const
+{
+        // If a scope has been specified use that as a starting point for the
+	// search
+      if (scope)
+	    s = des->find_package(scope->pscope_name());
+
+      if (!type->name.nil())
+	    s = s->find_typedef_scope(des, type);
+
+      return s;
+}
diff --git a/ivtest/ivltests/module_port_typedef_vector.v b/ivtest/ivltests/module_port_typedef_vector.v
new file mode 100644
index 000000000..ca5d4592a
--- /dev/null
+++ b/ivtest/ivltests/module_port_typedef_vector.v
@@ -0,0 +1,29 @@
+// Check that a packed array type identifier used for a module port is
+// elaborated in the correct scope.
+
+localparam A = 2;
+
+typedef logic [A-1:0] T;
+
+module test (
+  input T x
+);
+
+  localparam A = 5;
+
+  bit failed = 1'b0;
+
+  `define check(expr, val) \
+    if (expr !== val) begin \
+      $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+      failed = 1'b1; \
+    end
+
+  initial begin
+    `check($bits(x), 2);
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule
diff --git a/ivtest/ivltests/sv_ps_type_cast1.v b/ivtest/ivltests/sv_ps_type_cast1.v
new file mode 100644
index 000000000..305b05326
--- /dev/null
+++ b/ivtest/ivltests/sv_ps_type_cast1.v
@@ -0,0 +1,26 @@
+// Check that it is possible to reference a package scoped type identifier as
+// the type in a type cast expression.
+
+bit failed = 1'b0;
+
+`define check(expr, val) \
+  if (expr !== val) begin \
+    $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+    failed = 1'b1; \
+  end
+
+package P;
+  typedef integer T;
+endpackage
+
+module test;
+  integer x;
+  initial begin
+    x = P::T'(-1024.123);
+    `check(x, -1024)
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+endmodule
diff --git a/ivtest/ivltests/sv_ps_type_cast2.v b/ivtest/ivltests/sv_ps_type_cast2.v
new file mode 100644
index 000000000..61ea62bb7
--- /dev/null
+++ b/ivtest/ivltests/sv_ps_type_cast2.v
@@ -0,0 +1,28 @@
+// Check that it is possible to reference a package scoped type identifier as
+// the type in a type cast expression, even if there is a identifier of the same
+// name in the local scope.
+
+bit failed = 1'b0;
+
+`define check(expr, val) \
+  if (expr !== val) begin \
+    $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+    failed = 1'b1; \
+  end
+
+package P;
+  typedef integer T;
+endpackage
+
+module test;
+  localparam T = 2;
+  integer x;
+  initial begin
+    x = P::T'(-1024.123);
+   `check(x, -1024)
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+endmodule
diff --git a/ivtest/ivltests/sv_ps_type_class1.v b/ivtest/ivltests/sv_ps_type_class1.v
new file mode 100644
index 000000000..4742a8c8e
--- /dev/null
+++ b/ivtest/ivltests/sv_ps_type_class1.v
@@ -0,0 +1,39 @@
+// Check that class types declared in a package can be referenced using a scoped
+// type identifier.
+
+bit failed = 1'b0;
+
+`define check(expr, val) \
+  if (expr !== val) begin \
+    $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+    failed = 1'b1; \
+  end
+
+package P;
+
+  localparam A = 8;
+
+  class C;
+    logic [A-1:0] x;
+
+    task t;
+      `check($bits(x), 8)
+      if (!failed) begin
+        $display("PASSED");
+      end
+    endtask
+  endclass
+
+endpackage
+
+module test;
+
+  localparam A = 4;
+  P::C c;
+
+  initial begin
+    c = new;
+    c.t();
+  end
+
+endmodule
diff --git a/ivtest/ivltests/sv_ps_type_enum1.v b/ivtest/ivltests/sv_ps_type_enum1.v
new file mode 100644
index 000000000..4745a218f
--- /dev/null
+++ b/ivtest/ivltests/sv_ps_type_enum1.v
@@ -0,0 +1,38 @@
+// Check that enum types declared in a package can be referenced using a scoped
+// type identifier.
+
+bit failed = 1'b0;
+
+`define check(expr, val) \
+  if (expr !== val) begin \
+    $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+    failed = 1'b1; \
+  end
+
+package P;
+
+  localparam X = 8;
+
+  typedef enum logic [X-1:0] {
+    A, B = X
+  } T;
+
+endpackage
+
+module test;
+  localparam X = 4;
+
+  typedef int T;
+
+  P::T x = P::B;
+
+  initial begin
+    `check(x, P::B)
+    `check(x, 8)
+    `check($bits(x), 8);
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule
diff --git a/ivtest/ivltests/sv_ps_type_expr1.v b/ivtest/ivltests/sv_ps_type_expr1.v
new file mode 100644
index 000000000..7ce97f2f7
--- /dev/null
+++ b/ivtest/ivltests/sv_ps_type_expr1.v
@@ -0,0 +1,24 @@
+// Check that it is possible to reference a package scoped type identifier in an
+// expression.
+
+bit failed = 1'b0;
+
+`define check(expr, val) \
+  if (expr !== val) begin \
+    $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+    failed = 1'b1; \
+  end
+
+package P;
+  typedef integer T;
+endpackage
+
+module test;
+  initial begin
+    `check($bits(P::T), $bits(integer))
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+endmodule
diff --git a/ivtest/ivltests/sv_ps_type_expr2.v b/ivtest/ivltests/sv_ps_type_expr2.v
new file mode 100644
index 000000000..30ca5b246
--- /dev/null
+++ b/ivtest/ivltests/sv_ps_type_expr2.v
@@ -0,0 +1,26 @@
+// Check that it is possible to reference a package scoped type identifier in an
+// expression, even if there is a non type identifier of the same name in the
+// current scope.
+
+bit failed = 1'b0;
+
+`define check(expr, val) \
+  if (expr !== val) begin \
+    $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+    failed = 1'b1; \
+  end
+
+package P;
+  typedef integer T;
+endpackage
+
+module test;
+  integer T;
+  initial begin
+    `check($bits(P::T), $bits(integer))
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+endmodule
diff --git a/ivtest/ivltests/sv_ps_type_struct1.v b/ivtest/ivltests/sv_ps_type_struct1.v
new file mode 100644
index 000000000..3ec1b545d
--- /dev/null
+++ b/ivtest/ivltests/sv_ps_type_struct1.v
@@ -0,0 +1,40 @@
+// Check that struct types declared in a package can be referenced using a
+// scoped type identifier.
+
+bit failed = 1'b0;
+
+`define check(expr, val) \
+  if (expr !== val) begin \
+    $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+    failed = 1'b1; \
+  end
+
+package P;
+
+  localparam A = 8;
+
+  typedef struct packed {
+    logic [A-1:0] x;
+  } T;
+
+endpackage
+
+typedef int T;
+
+module test;
+  localparam A = 4;
+
+  typedef int T;
+
+  P::T x;
+
+  initial begin
+    x = 8'hff;
+    `check(x, 8'hff)
+    `check($bits(x), 8)
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule
diff --git a/ivtest/ivltests/sv_typedef_chained.v b/ivtest/ivltests/sv_typedef_chained.v
new file mode 100644
index 000000000..d62399cec
--- /dev/null
+++ b/ivtest/ivltests/sv_typedef_chained.v
@@ -0,0 +1,51 @@
+// Check that chained type definitions declared in different scopes work
+// correctly.
+
+package P1;
+  localparam A = 8;
+  typedef logic [A-1:0] T;
+endpackage
+
+package P2;
+  localparam A = 4;
+  typedef P1::T T;
+endpackage
+
+bit failed = 1'b0;
+
+`define check(expr, val) \
+  if (expr !== val) begin \
+    $display("FAILED: %s, expected %0d, got %0d", `"expr`", val, expr); \
+    failed = 1'b1; \
+  end
+
+module test;
+  localparam A = 2;
+
+  typedef P2::T T;
+
+  T x;
+  P1::T y;
+  P2::T z;
+
+  initial begin
+    x = 8'hff;
+    y = 8'hff;
+    z = 8'hff;
+
+    `check(x, 8'hff);
+    `check($bits(T), 8);
+    `check($bits(x), 8);
+    `check(y, 8'hff);
+    `check($bits(y), 8);
+    `check($bits(P1::T), 8);
+    `check(z, 8'hff);
+    `check($bits(z), 8);
+    `check($bits(P2::T), 8);
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule
diff --git a/ivtest/regress-sv.list b/ivtest/regress-sv.list
index 83cf8df61..2ac65d99d 100644
--- a/ivtest/regress-sv.list
+++ b/ivtest/regress-sv.list
@@ -372,6 +372,7 @@ module_nonansi_struct_fail CE,-g2005-sv	ivltests
 module_output_port_sv_var1 normal,-g2005-sv	ivltests
 module_output_port_sv_var2 normal,-g2005-sv	ivltests
 module_port_typedef_array1 normal,-g2005-sv	ivltests
+module_port_typedef_vector normal,-g2005-sv	ivltests
 named_begin		normal,-g2009		ivltests
 named_begin_fail	CE,-g2009		ivltests
 named_fork		normal,-g2009		ivltests
@@ -634,6 +635,13 @@ sv_ps_function2		normal,-g2009		ivltests
 sv_ps_function3		normal,-g2009		ivltests
 sv_ps_function4		normal,-g2009		ivltests
 sv_ps_type1		normal,-g2009		ivltests
+sv_ps_type_cast1	normal,-g2009		ivltests
+sv_ps_type_cast2	normal,-g2009		ivltests
+sv_ps_type_class1	normal,-g2009		ivltests
+sv_ps_type_enum1	normal,-g2009		ivltests
+sv_ps_type_expr1	normal,-g2009		ivltests
+sv_ps_type_expr2	normal,-g2009		ivltests
+sv_ps_type_struct1	normal,-g2009		ivltests
 sv_ps_var1		normal,-g2009		ivltests
 sv_queue1		normal,-g2009		ivltests
 sv_queue2		normal,-g2009		ivltests
@@ -705,6 +713,7 @@ sv_typedef_array_base1	normal,-g2009		ivltests
 sv_typedef_array_base2	normal,-g2009		ivltests
 sv_typedef_array_base3	normal,-g2009		ivltests
 sv_typedef_array_base4	normal,-g2009		ivltests
+sv_typedef_chained	normal,-g2009		ivltests
 sv_typedef_darray_base1	normal,-g2009		ivltests
 sv_typedef_darray_base2	normal,-g2009		ivltests
 sv_typedef_darray_base3	normal,-g2009		ivltests
diff --git a/ivtest/regress-vlog95.list b/ivtest/regress-vlog95.list
index cde38066f..bec2bf336 100644
--- a/ivtest/regress-vlog95.list
+++ b/ivtest/regress-vlog95.list
@@ -438,6 +438,7 @@ sv_port_default6	CE,-g2009,-pallowsigned=1	ivltests
 sv_port_default7	CE,-g2009,-pallowsigned=1	ivltests
 sv_port_default8	CE,-g2009,-pallowsigned=1	ivltests
 sv_port_default9	CE,-g2009		ivltests
+sv_ps_type_class1	CE,-g2009		ivltests
 sv_root_class		CE,-g2009		ivltests
 sv_typedef_scope3	CE,-g2009		ivltests
 sv_unit2b		CE,-g2009		ivltests
diff --git a/net_func_eval.cc b/net_func_eval.cc
index 58b7d629d..278e17299 100644
--- a/net_func_eval.cc
+++ b/net_func_eval.cc
@@ -23,10 +23,6 @@
 # include  <typeinfo>
 # include  "ivl_assert.h"
 
-#if __cplusplus < 201103L
-#define unique_ptr auto_ptr
-#endif
-
 using namespace std;
 
 /*
diff --git a/parse.y b/parse.y
index 16ba324d4..e27c35cd4 100644
--- a/parse.y
+++ b/parse.y
@@ -28,6 +28,7 @@
 # include  "pform.h"
 # include  "Statement.h"
 # include  "PSpec.h"
+# include  "PPackage.h"
 # include  <stack>
 # include  <cstring>
 # include  <sstream>
@@ -825,20 +826,9 @@ class_identifier
      the class name is detected by the lexor as a TYPE_IDENTIFIER if it
      does indeed match a name. */
 class_declaration_endlabel_opt
-  : ':' TYPE_IDENTIFIER
-      { class_type_t*tmp = dynamic_cast<class_type_t*> ($2.type);
-	if (tmp == 0) {
-	      yyerror(@2, "error: class declaration endlabel \"%s\" is not a class name\n", $2.text);
-	      $$ = 0;
-	} else {
-	      $$ = strdupnew(tmp->name.str());
-	}
-	delete[]$2.text;
-      }
-  | ':' IDENTIFIER
-      { $$ = $2; }
-  |
-      { $$ = 0; }
+  : ':' TYPE_IDENTIFIER { $$ = $2.text; }
+  | ':' IDENTIFIER { $$ = $2; }
+  | { $$ = 0; }
   ;
 
   /* This rule implements [ extends class_type ] in the
@@ -1179,12 +1169,14 @@ ps_type_identifier /* IEEE1800-2017: A.9.3 */
  : TYPE_IDENTIFIER
       { pform_set_type_referenced(@1, $1.text);
 	delete[]$1.text;
-	$$ = $1.type;
+	$$ = new typeref_t($1.type);
+	FILE_NAME($$, @1);
       }
   | package_scope TYPE_IDENTIFIER
       { lex_in_package_scope(0);
-	$$ = $2.type;
-	delete[]$2.text;
+	$$ = new typeref_t($2.type, $1);
+	FILE_NAME($$, @2);
+	delete[] $2.text;
       }
   ;
 
diff --git a/pform_dump.cc b/pform_dump.cc
index 4e1be9146..f6bc1c1b3 100644
--- a/pform_dump.cc
+++ b/pform_dump.cc
@@ -173,6 +173,15 @@ ostream& data_type_t::debug_dump(ostream&out) const
       return out;
 }
 
+std::ostream& typeref_t::debug_dump(ostream&out) const
+{
+      if (scope)
+	    out << scope->pscope_name() << "::";
+      out << type->name;
+
+      return out;
+}
+
 ostream& atom_type_t::debug_dump(ostream&out) const
 {
       if (signed_flag)
diff --git a/pform_pclass.cc b/pform_pclass.cc
index 5d0745b88..f1692ad4f 100644
--- a/pform_pclass.cc
+++ b/pform_pclass.cc
@@ -51,7 +51,7 @@ void pform_start_class_declaration(const struct vlltype&loc,
       pform_cur_class = class_scope;
 
       assert(type->base_type == 0);
-      type->base_type = base_type;
+      type->base_type.reset(base_type);
 
       assert(type->base_args.empty());
       if (base_exprs) {
diff --git a/pform_types.h b/pform_types.h
index 557b2a268..2ef0585c6 100644
--- a/pform_types.h
+++ b/pform_types.h
@@ -33,10 +33,6 @@
 # include  <map>
 # include  <memory>
 
-#if __cplusplus < 201103L
-#define unique_ptr auto_ptr
-#endif
-
 /*
  * parse-form types.
  */
@@ -45,6 +41,7 @@ class Design;
 class NetScope;
 class Definitions;
 class PExpr;
+class PScope;
 class PWire;
 class Statement;
 class netclass_t;
@@ -165,6 +162,8 @@ class data_type_t : public PNamedItem {
 
       virtual SymbolType symbol_type() const;
 
+      virtual NetScope *find_scope(Design* des, NetScope *scope) const;
+
       perm_string name;
 
     private:
@@ -175,6 +174,19 @@ class data_type_t : public PNamedItem {
       std::map<Definitions*,ivl_type_t> cache_type_elaborate_;
 };
 
+struct typeref_t : public data_type_t {
+      explicit typeref_t(data_type_t *t, PScope *s = 0) : scope(s), type(t) {}
+
+      ivl_type_t elaborate_type_raw(Design*des, NetScope*scope) const;
+      NetScope *find_scope(Design* des, NetScope *scope) const;
+
+      std::ostream& debug_dump(std::ostream&out) const;
+
+private:
+      PScope *scope;
+      data_type_t *type;
+};
+
 struct void_type_t : public data_type_t {
       virtual void pform_dump(std::ostream&out, unsigned indent) const;
 };
@@ -193,7 +205,7 @@ struct enum_type_t : public data_type_t {
 
       SymbolType symbol_type() const;
 
-      data_type_t *base_type;
+      std::unique_ptr<data_type_t> base_type;
       std::unique_ptr< std::list<named_pexpr_t> > names;
 };
 
@@ -270,7 +282,7 @@ struct array_base_t : public data_type_t {
       inline explicit array_base_t(data_type_t*btype, std::list<pform_range_t>*pd)
       : base_type(btype), dims(pd) { }
 
-      data_type_t*base_type;
+      std::unique_ptr<data_type_t> base_type;
       std::unique_ptr< std::list<pform_range_t> > dims;
 };
 
@@ -323,8 +335,7 @@ struct string_type_t : public data_type_t {
 
 struct class_type_t : public data_type_t {
 
-      inline explicit class_type_t(perm_string n)
-      : base_type(0), save_elaborated_type(0) { name = n; }
+      inline explicit class_type_t(perm_string n) { name = n; }
 
       void pform_dump(std::ostream&out, unsigned indent) const;
       void pform_dump_init(std::ostream&out, unsigned indent) const;
@@ -333,15 +344,17 @@ struct class_type_t : public data_type_t {
 	// class that we are extending. This is nil if there is no
 	// hierarchy. If there are arguments to the base class, then
 	// put them in the base_args vector.
-      data_type_t*base_type;
+      std::unique_ptr<data_type_t> base_type;
       std::list<PExpr*>base_args;
 
 	// This is a map of the properties. Map the name to the type.
       struct prop_info_t : public LineInfo {
-	    inline prop_info_t() : qual(property_qualifier_t::make_none()), type(0) { }
+	    inline prop_info_t() : qual(property_qualifier_t::make_none()) { }
 	    inline prop_info_t(property_qualifier_t q, data_type_t*t) : qual(q), type(t) { }
+	    prop_info_t(prop_info_t&&) = default;
+	    prop_info_t& operator=(prop_info_t&&) = default;
 	    property_qualifier_t qual;
-	    data_type_t* type;
+	    std::unique_ptr<data_type_t> type;
       };
       std::map<perm_string, struct prop_info_t> properties;
 
@@ -356,11 +369,6 @@ struct class_type_t : public data_type_t {
       std::vector<Statement*> initialize_static;
 
       ivl_type_t elaborate_type_raw(Design*, NetScope*) const;
-	// The save_elaborated_type member must be set to the pointer
-	// to the netclass_t object that is created to represent this
-	// type. The elaborate_type_raw() method uses this pointer,
-	// and it is used in some other situations as well.
-      netclass_t* save_elaborated_type;
 
       virtual SymbolType symbol_type() const;
 };
@@ -425,8 +433,4 @@ extern std::ostream& operator<< (std::ostream&out, const pform_name_t&);
 extern std::ostream& operator<< (std::ostream&out, const name_component_t&that);
 extern std::ostream& operator<< (std::ostream&out, const index_component_t&that);
 
-#if __cplusplus < 201103L
-#undef unique_ptr
-#endif
-
 #endif /* IVL_pform_types_H */