vhdl08: more support for interface subprograms.

14 files changed, 520 insertions, 234 deletions

diff --git a/src/vhdl/canon.adb b/src/vhdl/canon.adb
index 028a9819c..3fe106861 100644
--- a/src/vhdl/canon.adb
+++ b/src/vhdl/canon.adb
@@ -890,7 +890,8 @@ package body Canon is
                   when Iir_Kind_Association_Element_By_Individual =>
                      Found := True;
                   when Iir_Kind_Association_Element_Package
-                    | Iir_Kind_Association_Element_Type =>
+                    | Iir_Kind_Association_Element_Type
+                    | Iir_Kind_Association_Element_Subprogram =>
                      goto Done;
                   when others =>
                      Error_Kind ("canon_association_chain", Assoc_El);
diff --git a/src/vhdl/disp_vhdl.adb b/src/vhdl/disp_vhdl.adb
index 8ceab99cf..646630602 100644
--- a/src/vhdl/disp_vhdl.adb
+++ b/src/vhdl/disp_vhdl.adb
@@ -832,13 +832,11 @@ package body Disp_Vhdl is
 
    procedure Disp_Type_Declaration (Decl: Iir_Type_Declaration)
    is
-      Indent: Count;
-      Def : Iir;
+      Indent : constant Count := Col;
+      Def : constant Iir := Get_Type_Definition (Decl);
    begin
-      Indent := Col;
       Put ("type ");
       Disp_Name_Of (Decl);
-      Def := Get_Type_Definition (Decl);
       if Def = Null_Iir
         or else Get_Kind (Def) = Iir_Kind_Incomplete_Type_Definition
       then
@@ -1114,6 +1112,8 @@ package body Disp_Vhdl is
             when Iir_Kind_Interface_Type_Declaration =>
                Put ("type ");
                Disp_Identifier (Inter);
+            when Iir_Kinds_Interface_Subprogram_Declaration =>
+               Disp_Subprogram_Declaration (Inter);
             when others =>
                Error_Kind ("disp_interface_chain", Inter);
          end case;
@@ -1434,13 +1434,15 @@ package body Disp_Vhdl is
       end if;
 
       case Get_Kind (Subprg) is
-         when Iir_Kind_Function_Declaration =>
+         when Iir_Kind_Function_Declaration
+           | Iir_Kind_Interface_Function_Declaration =>
             if Get_Has_Pure (Subprg) then
                Disp_Pure (Subprg);
                Put (' ');
             end if;
             Put ("function");
-         when Iir_Kind_Procedure_Declaration =>
+         when Iir_Kind_Procedure_Declaration
+           | Iir_Kind_Interface_Procedure_Declaration =>
             Put ("procedure");
          when others =>
             raise Internal_Error;
@@ -1457,14 +1459,16 @@ package body Disp_Vhdl is
       end if;
 
       case Get_Kind (Subprg) is
-         when Iir_Kind_Function_Declaration =>
+         when Iir_Kind_Function_Declaration
+           | Iir_Kind_Interface_Function_Declaration =>
             Put (" return ");
             if Implicit then
                Disp_Type (Get_Return_Type (Subprg));
             else
                Disp_Name (Get_Return_Type_Mark (Subprg));
             end if;
-         when Iir_Kind_Procedure_Declaration =>
+         when Iir_Kind_Procedure_Declaration
+           | Iir_Kind_Interface_Procedure_Declaration =>
             null;
          when others =>
             raise Internal_Error;
@@ -1713,7 +1717,7 @@ package body Disp_Vhdl is
             when Iir_Kind_Function_Body
               | Iir_Kind_Procedure_Body =>
                --  The declaration was just displayed.
-               Put_Line (" is");
+               Put_Line ("is");
                Set_Col (Indent);
                Disp_Subprogram_Body (Decl);
             when Iir_Kind_Protected_Type_Body =>
diff --git a/src/vhdl/iir_chains.adb b/src/vhdl/iir_chains.adb
index d6d944f4e..43d02d44f 100644
--- a/src/vhdl/iir_chains.adb
+++ b/src/vhdl/iir_chains.adb
@@ -28,6 +28,28 @@ package body Iir_Chains is
       return Res;
    end Get_Chain_Length;
 
+   procedure Append_Chain
+     (N : Iir; Field : Nodes_Meta.Fields_Enum; Chain : Iir)
+   is
+      use Nodes_Meta;
+      N_Chain : Iir;
+      Next_Chain : Iir;
+   begin
+      N_Chain := Get_Iir (N, Field);
+      if Is_Null (N_Chain) then
+         Set_Iir (N, Field, Chain);
+      else
+         loop
+            Next_Chain := Get_Chain (N_Chain);
+            if Is_Null (Next_Chain) then
+               Set_Chain (N_Chain, Chain);
+               exit;
+            end if;
+            N_Chain := Next_Chain;
+         end loop;
+      end if;
+   end Append_Chain;
+
    procedure Sub_Chain_Init (First, Last : out Iir) is
    begin
       First := Null_Iir;
diff --git a/src/vhdl/iir_chains.ads b/src/vhdl/iir_chains.ads
index 85746f154..fc9da1136 100644
--- a/src/vhdl/iir_chains.ads
+++ b/src/vhdl/iir_chains.ads
@@ -18,6 +18,7 @@
 with Iirs; use Iirs;
 with Iir_Chain_Handling;
 pragma Elaborate_All (Iir_Chain_Handling);
+with Nodes_Meta;
 
 package Iir_Chains is
    --  Chains are simply linked list of iirs.
@@ -84,6 +85,10 @@ package Iir_Chains is
    --  Not very efficient since O(N).
    function Get_Chain_Length (First : Iir) return Natural;
 
+   --  Append CHAIN to the chain FIELD of node N.  Not very efficient.
+   procedure Append_Chain
+     (N : Iir; Field : Nodes_Meta.Fields_Enum; Chain : Iir);
+
    --  These two subprograms can be used to build a sub-chain.
    --  FIRST and LAST designates respectively the first and last element of
    --  the sub-chain.
diff --git a/src/vhdl/iirs.adb b/src/vhdl/iirs.adb
index 1cf90d515..787be2df1 100644
--- a/src/vhdl/iirs.adb
+++ b/src/vhdl/iirs.adb
@@ -2478,6 +2478,22 @@ package body Iirs is
       Set_Field3 (Def, Decl);
    end Set_Type_Declarator;
 
+   function Get_Associated_Type (Def : Iir) return Iir is
+   begin
+      pragma Assert (Def /= Null_Iir);
+      pragma Assert (Has_Associated_Type (Get_Kind (Def)),
+                     "no field Associated_Type");
+      return Get_Field5 (Def);
+   end Get_Associated_Type;
+
+   procedure Set_Associated_Type (Def : Iir; Atype : Iir) is
+   begin
+      pragma Assert (Def /= Null_Iir);
+      pragma Assert (Has_Associated_Type (Get_Kind (Def)),
+                     "no field Associated_Type");
+      Set_Field5 (Def, Atype);
+   end Set_Associated_Type;
+
    function Get_Enumeration_Literal_List (Target : Iir) return Iir_List is
    begin
       pragma Assert (Target /= Null_Iir);
diff --git a/src/vhdl/iirs.ads b/src/vhdl/iirs.ads
index 75d569377..8f2d21c29 100644
--- a/src/vhdl/iirs.ads
+++ b/src/vhdl/iirs.ads
@@ -2221,6 +2221,11 @@ package Iirs is
    --
    --   Get/Set_Base_Type (Field4)
    --
+   --  Set only during analysis of association: type associated with this
+   --  interface, so that references to this interface can use the actual
+   --  type.
+   --   Get/Set_Associated_Type (Field5)
+   --
    --   Get/Set_Type_Staticness (State1)
    --
    --   Get/Set_Resolved_Flag (Flag1)
@@ -6072,6 +6077,10 @@ package Iirs is
    function Get_Type_Declarator (Def : Iir) return Iir;
    procedure Set_Type_Declarator (Def : Iir; Decl : Iir);
 
+   --  Field: Field5 Ref
+   function Get_Associated_Type (Def : Iir) return Iir;
+   procedure Set_Associated_Type (Def : Iir; Atype : Iir);
+
    --  Field: Field2 (uc)
    function Get_Enumeration_Literal_List (Target : Iir) return Iir_List;
    procedure Set_Enumeration_Literal_List (Target : Iir; List : Iir_List);
diff --git a/src/vhdl/nodes_meta.adb b/src/vhdl/nodes_meta.adb
index 71cb3a684..8cbb22906 100644
--- a/src/vhdl/nodes_meta.adb
+++ b/src/vhdl/nodes_meta.adb
@@ -140,6 +140,7 @@ package body Nodes_Meta is
       Field_Context_Reference_Chain => Type_Iir,
       Field_Selected_Name => Type_Iir,
       Field_Type_Declarator => Type_Iir,
+      Field_Associated_Type => Type_Iir,
       Field_Enumeration_Literal_List => Type_Iir_List,
       Field_Entity_Class_Entry_Chain => Type_Iir,
       Field_Group_Constituent_List => Type_Iir_List,
@@ -581,6 +582,8 @@ package body Nodes_Meta is
             return "selected_name";
          when Field_Type_Declarator =>
             return "type_declarator";
+         when Field_Associated_Type =>
+            return "associated_type";
          when Field_Enumeration_Literal_List =>
             return "enumeration_literal_list";
          when Field_Entity_Class_Entry_Chain =>
@@ -1737,6 +1740,8 @@ package body Nodes_Meta is
             return Attr_None;
          when Field_Type_Declarator =>
             return Attr_Ref;
+         when Field_Associated_Type =>
+            return Attr_Ref;
          when Field_Enumeration_Literal_List =>
             return Attr_None;
          when Field_Entity_Class_Entry_Chain =>
@@ -2430,6 +2435,7 @@ package body Nodes_Meta is
       Field_Type_Staticness,
       Field_Type_Declarator,
       Field_Base_Type,
+      Field_Associated_Type,
       --  Iir_Kind_File_Type_Definition
       Field_Resolved_Flag,
       Field_Signal_Type_Flag,
@@ -4251,218 +4257,218 @@ package body Nodes_Meta is
       Iir_Kind_Configuration_Specification => 238,
       Iir_Kind_Access_Type_Definition => 245,
       Iir_Kind_Incomplete_Type_Definition => 252,
-      Iir_Kind_Interface_Type_Definition => 258,
-      Iir_Kind_File_Type_Definition => 265,
-      Iir_Kind_Protected_Type_Declaration => 274,
-      Iir_Kind_Record_Type_Definition => 284,
-      Iir_Kind_Array_Type_Definition => 296,
-      Iir_Kind_Array_Subtype_Definition => 311,
-      Iir_Kind_Record_Subtype_Definition => 322,
-      Iir_Kind_Access_Subtype_Definition => 330,
-      Iir_Kind_Physical_Subtype_Definition => 339,
-      Iir_Kind_Floating_Subtype_Definition => 349,
-      Iir_Kind_Integer_Subtype_Definition => 358,
-      Iir_Kind_Enumeration_Subtype_Definition => 367,
-      Iir_Kind_Enumeration_Type_Definition => 376,
-      Iir_Kind_Integer_Type_Definition => 382,
-      Iir_Kind_Floating_Type_Definition => 388,
-      Iir_Kind_Physical_Type_Definition => 397,
-      Iir_Kind_Range_Expression => 403,
-      Iir_Kind_Protected_Type_Body => 410,
-      Iir_Kind_Wildcard_Type_Definition => 415,
-      Iir_Kind_Subtype_Definition => 419,
-      Iir_Kind_Scalar_Nature_Definition => 423,
-      Iir_Kind_Overload_List => 424,
-      Iir_Kind_Type_Declaration => 430,
-      Iir_Kind_Anonymous_Type_Declaration => 435,
-      Iir_Kind_Subtype_Declaration => 443,
-      Iir_Kind_Nature_Declaration => 449,
-      Iir_Kind_Subnature_Declaration => 455,
-      Iir_Kind_Package_Declaration => 470,
-      Iir_Kind_Package_Instantiation_Declaration => 482,
-      Iir_Kind_Package_Body => 490,
-      Iir_Kind_Configuration_Declaration => 499,
-      Iir_Kind_Entity_Declaration => 511,
-      Iir_Kind_Architecture_Body => 523,
-      Iir_Kind_Context_Declaration => 529,
-      Iir_Kind_Package_Header => 531,
-      Iir_Kind_Unit_Declaration => 540,
-      Iir_Kind_Library_Declaration => 547,
-      Iir_Kind_Component_Declaration => 557,
-      Iir_Kind_Attribute_Declaration => 564,
-      Iir_Kind_Group_Template_Declaration => 570,
-      Iir_Kind_Group_Declaration => 577,
-      Iir_Kind_Element_Declaration => 584,
-      Iir_Kind_Non_Object_Alias_Declaration => 592,
-      Iir_Kind_Psl_Declaration => 600,
-      Iir_Kind_Psl_Endpoint_Declaration => 614,
-      Iir_Kind_Terminal_Declaration => 620,
-      Iir_Kind_Free_Quantity_Declaration => 629,
-      Iir_Kind_Across_Quantity_Declaration => 641,
-      Iir_Kind_Through_Quantity_Declaration => 653,
-      Iir_Kind_Enumeration_Literal => 664,
-      Iir_Kind_Function_Declaration => 688,
-      Iir_Kind_Procedure_Declaration => 711,
-      Iir_Kind_Function_Body => 721,
-      Iir_Kind_Procedure_Body => 732,
-      Iir_Kind_Object_Alias_Declaration => 744,
-      Iir_Kind_File_Declaration => 759,
-      Iir_Kind_Guard_Signal_Declaration => 772,
-      Iir_Kind_Signal_Declaration => 789,
-      Iir_Kind_Variable_Declaration => 802,
-      Iir_Kind_Constant_Declaration => 816,
-      Iir_Kind_Iterator_Declaration => 828,
-      Iir_Kind_Interface_Constant_Declaration => 844,
-      Iir_Kind_Interface_Variable_Declaration => 860,
-      Iir_Kind_Interface_Signal_Declaration => 881,
-      Iir_Kind_Interface_File_Declaration => 897,
-      Iir_Kind_Interface_Type_Declaration => 907,
-      Iir_Kind_Interface_Package_Declaration => 917,
-      Iir_Kind_Interface_Function_Declaration => 933,
-      Iir_Kind_Interface_Procedure_Declaration => 945,
-      Iir_Kind_Identity_Operator => 949,
-      Iir_Kind_Negation_Operator => 953,
-      Iir_Kind_Absolute_Operator => 957,
-      Iir_Kind_Not_Operator => 961,
-      Iir_Kind_Condition_Operator => 965,
-      Iir_Kind_Reduction_And_Operator => 969,
-      Iir_Kind_Reduction_Or_Operator => 973,
-      Iir_Kind_Reduction_Nand_Operator => 977,
-      Iir_Kind_Reduction_Nor_Operator => 981,
-      Iir_Kind_Reduction_Xor_Operator => 985,
-      Iir_Kind_Reduction_Xnor_Operator => 989,
-      Iir_Kind_And_Operator => 994,
-      Iir_Kind_Or_Operator => 999,
-      Iir_Kind_Nand_Operator => 1004,
-      Iir_Kind_Nor_Operator => 1009,
-      Iir_Kind_Xor_Operator => 1014,
-      Iir_Kind_Xnor_Operator => 1019,
-      Iir_Kind_Equality_Operator => 1024,
-      Iir_Kind_Inequality_Operator => 1029,
-      Iir_Kind_Less_Than_Operator => 1034,
-      Iir_Kind_Less_Than_Or_Equal_Operator => 1039,
-      Iir_Kind_Greater_Than_Operator => 1044,
-      Iir_Kind_Greater_Than_Or_Equal_Operator => 1049,
-      Iir_Kind_Match_Equality_Operator => 1054,
-      Iir_Kind_Match_Inequality_Operator => 1059,
-      Iir_Kind_Match_Less_Than_Operator => 1064,
-      Iir_Kind_Match_Less_Than_Or_Equal_Operator => 1069,
-      Iir_Kind_Match_Greater_Than_Operator => 1074,
-      Iir_Kind_Match_Greater_Than_Or_Equal_Operator => 1079,
-      Iir_Kind_Sll_Operator => 1084,
-      Iir_Kind_Sla_Operator => 1089,
-      Iir_Kind_Srl_Operator => 1094,
-      Iir_Kind_Sra_Operator => 1099,
-      Iir_Kind_Rol_Operator => 1104,
-      Iir_Kind_Ror_Operator => 1109,
-      Iir_Kind_Addition_Operator => 1114,
-      Iir_Kind_Substraction_Operator => 1119,
-      Iir_Kind_Concatenation_Operator => 1124,
-      Iir_Kind_Multiplication_Operator => 1129,
-      Iir_Kind_Division_Operator => 1134,
-      Iir_Kind_Modulus_Operator => 1139,
-      Iir_Kind_Remainder_Operator => 1144,
-      Iir_Kind_Exponentiation_Operator => 1149,
-      Iir_Kind_Function_Call => 1157,
-      Iir_Kind_Aggregate => 1163,
-      Iir_Kind_Parenthesis_Expression => 1166,
-      Iir_Kind_Qualified_Expression => 1170,
-      Iir_Kind_Type_Conversion => 1175,
-      Iir_Kind_Allocator_By_Expression => 1179,
-      Iir_Kind_Allocator_By_Subtype => 1185,
-      Iir_Kind_Selected_Element => 1191,
-      Iir_Kind_Dereference => 1196,
-      Iir_Kind_Implicit_Dereference => 1201,
-      Iir_Kind_Slice_Name => 1208,
-      Iir_Kind_Indexed_Name => 1214,
-      Iir_Kind_Psl_Expression => 1216,
-      Iir_Kind_Sensitized_Process_Statement => 1236,
-      Iir_Kind_Process_Statement => 1256,
-      Iir_Kind_Concurrent_Simple_Signal_Assignment => 1267,
-      Iir_Kind_Concurrent_Conditional_Signal_Assignment => 1278,
-      Iir_Kind_Concurrent_Selected_Signal_Assignment => 1290,
-      Iir_Kind_Concurrent_Assertion_Statement => 1298,
-      Iir_Kind_Concurrent_Procedure_Call_Statement => 1305,
-      Iir_Kind_Psl_Assert_Statement => 1318,
-      Iir_Kind_Psl_Cover_Statement => 1331,
-      Iir_Kind_Block_Statement => 1344,
-      Iir_Kind_If_Generate_Statement => 1354,
-      Iir_Kind_Case_Generate_Statement => 1363,
-      Iir_Kind_For_Generate_Statement => 1372,
-      Iir_Kind_Component_Instantiation_Statement => 1382,
-      Iir_Kind_Psl_Default_Clock => 1386,
-      Iir_Kind_Simple_Simultaneous_Statement => 1393,
-      Iir_Kind_Generate_Statement_Body => 1404,
-      Iir_Kind_If_Generate_Else_Clause => 1409,
-      Iir_Kind_Simple_Signal_Assignment_Statement => 1418,
-      Iir_Kind_Conditional_Signal_Assignment_Statement => 1427,
-      Iir_Kind_Null_Statement => 1431,
-      Iir_Kind_Assertion_Statement => 1438,
-      Iir_Kind_Report_Statement => 1444,
-      Iir_Kind_Wait_Statement => 1451,
-      Iir_Kind_Variable_Assignment_Statement => 1457,
-      Iir_Kind_Conditional_Variable_Assignment_Statement => 1463,
-      Iir_Kind_Return_Statement => 1469,
-      Iir_Kind_For_Loop_Statement => 1478,
-      Iir_Kind_While_Loop_Statement => 1486,
-      Iir_Kind_Next_Statement => 1492,
-      Iir_Kind_Exit_Statement => 1498,
-      Iir_Kind_Case_Statement => 1506,
-      Iir_Kind_Procedure_Call_Statement => 1512,
-      Iir_Kind_If_Statement => 1521,
-      Iir_Kind_Elsif => 1526,
-      Iir_Kind_Character_Literal => 1533,
-      Iir_Kind_Simple_Name => 1540,
-      Iir_Kind_Selected_Name => 1548,
-      Iir_Kind_Operator_Symbol => 1553,
-      Iir_Kind_Selected_By_All_Name => 1558,
-      Iir_Kind_Parenthesis_Name => 1562,
-      Iir_Kind_External_Constant_Name => 1571,
-      Iir_Kind_External_Signal_Name => 1580,
-      Iir_Kind_External_Variable_Name => 1589,
-      Iir_Kind_Package_Pathname => 1592,
-      Iir_Kind_Absolute_Pathname => 1593,
-      Iir_Kind_Relative_Pathname => 1594,
-      Iir_Kind_Pathname_Element => 1598,
-      Iir_Kind_Base_Attribute => 1600,
-      Iir_Kind_Left_Type_Attribute => 1605,
-      Iir_Kind_Right_Type_Attribute => 1610,
-      Iir_Kind_High_Type_Attribute => 1615,
-      Iir_Kind_Low_Type_Attribute => 1620,
-      Iir_Kind_Ascending_Type_Attribute => 1625,
-      Iir_Kind_Image_Attribute => 1631,
-      Iir_Kind_Value_Attribute => 1637,
-      Iir_Kind_Pos_Attribute => 1643,
-      Iir_Kind_Val_Attribute => 1649,
-      Iir_Kind_Succ_Attribute => 1655,
-      Iir_Kind_Pred_Attribute => 1661,
-      Iir_Kind_Leftof_Attribute => 1667,
-      Iir_Kind_Rightof_Attribute => 1673,
-      Iir_Kind_Delayed_Attribute => 1681,
-      Iir_Kind_Stable_Attribute => 1689,
-      Iir_Kind_Quiet_Attribute => 1697,
-      Iir_Kind_Transaction_Attribute => 1705,
-      Iir_Kind_Event_Attribute => 1709,
-      Iir_Kind_Active_Attribute => 1713,
-      Iir_Kind_Last_Event_Attribute => 1717,
-      Iir_Kind_Last_Active_Attribute => 1721,
-      Iir_Kind_Last_Value_Attribute => 1725,
-      Iir_Kind_Driving_Attribute => 1729,
-      Iir_Kind_Driving_Value_Attribute => 1733,
-      Iir_Kind_Behavior_Attribute => 1733,
-      Iir_Kind_Structure_Attribute => 1733,
-      Iir_Kind_Simple_Name_Attribute => 1740,
-      Iir_Kind_Instance_Name_Attribute => 1745,
-      Iir_Kind_Path_Name_Attribute => 1750,
-      Iir_Kind_Left_Array_Attribute => 1757,
-      Iir_Kind_Right_Array_Attribute => 1764,
-      Iir_Kind_High_Array_Attribute => 1771,
-      Iir_Kind_Low_Array_Attribute => 1778,
-      Iir_Kind_Length_Array_Attribute => 1785,
-      Iir_Kind_Ascending_Array_Attribute => 1792,
-      Iir_Kind_Range_Array_Attribute => 1799,
-      Iir_Kind_Reverse_Range_Array_Attribute => 1806,
-      Iir_Kind_Attribute_Name => 1814
+      Iir_Kind_Interface_Type_Definition => 259,
+      Iir_Kind_File_Type_Definition => 266,
+      Iir_Kind_Protected_Type_Declaration => 275,
+      Iir_Kind_Record_Type_Definition => 285,
+      Iir_Kind_Array_Type_Definition => 297,
+      Iir_Kind_Array_Subtype_Definition => 312,
+      Iir_Kind_Record_Subtype_Definition => 323,
+      Iir_Kind_Access_Subtype_Definition => 331,
+      Iir_Kind_Physical_Subtype_Definition => 340,
+      Iir_Kind_Floating_Subtype_Definition => 350,
+      Iir_Kind_Integer_Subtype_Definition => 359,
+      Iir_Kind_Enumeration_Subtype_Definition => 368,
+      Iir_Kind_Enumeration_Type_Definition => 377,
+      Iir_Kind_Integer_Type_Definition => 383,
+      Iir_Kind_Floating_Type_Definition => 389,
+      Iir_Kind_Physical_Type_Definition => 398,
+      Iir_Kind_Range_Expression => 404,
+      Iir_Kind_Protected_Type_Body => 411,
+      Iir_Kind_Wildcard_Type_Definition => 416,
+      Iir_Kind_Subtype_Definition => 420,
+      Iir_Kind_Scalar_Nature_Definition => 424,
+      Iir_Kind_Overload_List => 425,
+      Iir_Kind_Type_Declaration => 431,
+      Iir_Kind_Anonymous_Type_Declaration => 436,
+      Iir_Kind_Subtype_Declaration => 444,
+      Iir_Kind_Nature_Declaration => 450,
+      Iir_Kind_Subnature_Declaration => 456,
+      Iir_Kind_Package_Declaration => 471,
+      Iir_Kind_Package_Instantiation_Declaration => 483,
+      Iir_Kind_Package_Body => 491,
+      Iir_Kind_Configuration_Declaration => 500,
+      Iir_Kind_Entity_Declaration => 512,
+      Iir_Kind_Architecture_Body => 524,
+      Iir_Kind_Context_Declaration => 530,
+      Iir_Kind_Package_Header => 532,
+      Iir_Kind_Unit_Declaration => 541,
+      Iir_Kind_Library_Declaration => 548,
+      Iir_Kind_Component_Declaration => 558,
+      Iir_Kind_Attribute_Declaration => 565,
+      Iir_Kind_Group_Template_Declaration => 571,
+      Iir_Kind_Group_Declaration => 578,
+      Iir_Kind_Element_Declaration => 585,
+      Iir_Kind_Non_Object_Alias_Declaration => 593,
+      Iir_Kind_Psl_Declaration => 601,
+      Iir_Kind_Psl_Endpoint_Declaration => 615,
+      Iir_Kind_Terminal_Declaration => 621,
+      Iir_Kind_Free_Quantity_Declaration => 630,
+      Iir_Kind_Across_Quantity_Declaration => 642,
+      Iir_Kind_Through_Quantity_Declaration => 654,
+      Iir_Kind_Enumeration_Literal => 665,
+      Iir_Kind_Function_Declaration => 689,
+      Iir_Kind_Procedure_Declaration => 712,
+      Iir_Kind_Function_Body => 722,
+      Iir_Kind_Procedure_Body => 733,
+      Iir_Kind_Object_Alias_Declaration => 745,
+      Iir_Kind_File_Declaration => 760,
+      Iir_Kind_Guard_Signal_Declaration => 773,
+      Iir_Kind_Signal_Declaration => 790,
+      Iir_Kind_Variable_Declaration => 803,
+      Iir_Kind_Constant_Declaration => 817,
+      Iir_Kind_Iterator_Declaration => 829,
+      Iir_Kind_Interface_Constant_Declaration => 845,
+      Iir_Kind_Interface_Variable_Declaration => 861,
+      Iir_Kind_Interface_Signal_Declaration => 882,
+      Iir_Kind_Interface_File_Declaration => 898,
+      Iir_Kind_Interface_Type_Declaration => 908,
+      Iir_Kind_Interface_Package_Declaration => 918,
+      Iir_Kind_Interface_Function_Declaration => 934,
+      Iir_Kind_Interface_Procedure_Declaration => 946,
+      Iir_Kind_Identity_Operator => 950,
+      Iir_Kind_Negation_Operator => 954,
+      Iir_Kind_Absolute_Operator => 958,
+      Iir_Kind_Not_Operator => 962,
+      Iir_Kind_Condition_Operator => 966,
+      Iir_Kind_Reduction_And_Operator => 970,
+      Iir_Kind_Reduction_Or_Operator => 974,
+      Iir_Kind_Reduction_Nand_Operator => 978,
+      Iir_Kind_Reduction_Nor_Operator => 982,
+      Iir_Kind_Reduction_Xor_Operator => 986,
+      Iir_Kind_Reduction_Xnor_Operator => 990,
+      Iir_Kind_And_Operator => 995,
+      Iir_Kind_Or_Operator => 1000,
+      Iir_Kind_Nand_Operator => 1005,
+      Iir_Kind_Nor_Operator => 1010,
+      Iir_Kind_Xor_Operator => 1015,
+      Iir_Kind_Xnor_Operator => 1020,
+      Iir_Kind_Equality_Operator => 1025,
+      Iir_Kind_Inequality_Operator => 1030,
+      Iir_Kind_Less_Than_Operator => 1035,
+      Iir_Kind_Less_Than_Or_Equal_Operator => 1040,
+      Iir_Kind_Greater_Than_Operator => 1045,
+      Iir_Kind_Greater_Than_Or_Equal_Operator => 1050,
+      Iir_Kind_Match_Equality_Operator => 1055,
+      Iir_Kind_Match_Inequality_Operator => 1060,
+      Iir_Kind_Match_Less_Than_Operator => 1065,
+      Iir_Kind_Match_Less_Than_Or_Equal_Operator => 1070,
+      Iir_Kind_Match_Greater_Than_Operator => 1075,
+      Iir_Kind_Match_Greater_Than_Or_Equal_Operator => 1080,
+      Iir_Kind_Sll_Operator => 1085,
+      Iir_Kind_Sla_Operator => 1090,
+      Iir_Kind_Srl_Operator => 1095,
+      Iir_Kind_Sra_Operator => 1100,
+      Iir_Kind_Rol_Operator => 1105,
+      Iir_Kind_Ror_Operator => 1110,
+      Iir_Kind_Addition_Operator => 1115,
+      Iir_Kind_Substraction_Operator => 1120,
+      Iir_Kind_Concatenation_Operator => 1125,
+      Iir_Kind_Multiplication_Operator => 1130,
+      Iir_Kind_Division_Operator => 1135,
+      Iir_Kind_Modulus_Operator => 1140,
+      Iir_Kind_Remainder_Operator => 1145,
+      Iir_Kind_Exponentiation_Operator => 1150,
+      Iir_Kind_Function_Call => 1158,
+      Iir_Kind_Aggregate => 1164,
+      Iir_Kind_Parenthesis_Expression => 1167,
+      Iir_Kind_Qualified_Expression => 1171,
+      Iir_Kind_Type_Conversion => 1176,
+      Iir_Kind_Allocator_By_Expression => 1180,
+      Iir_Kind_Allocator_By_Subtype => 1186,
+      Iir_Kind_Selected_Element => 1192,
+      Iir_Kind_Dereference => 1197,
+      Iir_Kind_Implicit_Dereference => 1202,
+      Iir_Kind_Slice_Name => 1209,
+      Iir_Kind_Indexed_Name => 1215,
+      Iir_Kind_Psl_Expression => 1217,
+      Iir_Kind_Sensitized_Process_Statement => 1237,
+      Iir_Kind_Process_Statement => 1257,
+      Iir_Kind_Concurrent_Simple_Signal_Assignment => 1268,
+      Iir_Kind_Concurrent_Conditional_Signal_Assignment => 1279,
+      Iir_Kind_Concurrent_Selected_Signal_Assignment => 1291,
+      Iir_Kind_Concurrent_Assertion_Statement => 1299,
+      Iir_Kind_Concurrent_Procedure_Call_Statement => 1306,
+      Iir_Kind_Psl_Assert_Statement => 1319,
+      Iir_Kind_Psl_Cover_Statement => 1332,
+      Iir_Kind_Block_Statement => 1345,
+      Iir_Kind_If_Generate_Statement => 1355,
+      Iir_Kind_Case_Generate_Statement => 1364,
+      Iir_Kind_For_Generate_Statement => 1373,
+      Iir_Kind_Component_Instantiation_Statement => 1383,
+      Iir_Kind_Psl_Default_Clock => 1387,
+      Iir_Kind_Simple_Simultaneous_Statement => 1394,
+      Iir_Kind_Generate_Statement_Body => 1405,
+      Iir_Kind_If_Generate_Else_Clause => 1410,
+      Iir_Kind_Simple_Signal_Assignment_Statement => 1419,
+      Iir_Kind_Conditional_Signal_Assignment_Statement => 1428,
+      Iir_Kind_Null_Statement => 1432,
+      Iir_Kind_Assertion_Statement => 1439,
+      Iir_Kind_Report_Statement => 1445,
+      Iir_Kind_Wait_Statement => 1452,
+      Iir_Kind_Variable_Assignment_Statement => 1458,
+      Iir_Kind_Conditional_Variable_Assignment_Statement => 1464,
+      Iir_Kind_Return_Statement => 1470,
+      Iir_Kind_For_Loop_Statement => 1479,
+      Iir_Kind_While_Loop_Statement => 1487,
+      Iir_Kind_Next_Statement => 1493,
+      Iir_Kind_Exit_Statement => 1499,
+      Iir_Kind_Case_Statement => 1507,
+      Iir_Kind_Procedure_Call_Statement => 1513,
+      Iir_Kind_If_Statement => 1522,
+      Iir_Kind_Elsif => 1527,
+      Iir_Kind_Character_Literal => 1534,
+      Iir_Kind_Simple_Name => 1541,
+      Iir_Kind_Selected_Name => 1549,
+      Iir_Kind_Operator_Symbol => 1554,
+      Iir_Kind_Selected_By_All_Name => 1559,
+      Iir_Kind_Parenthesis_Name => 1563,
+      Iir_Kind_External_Constant_Name => 1572,
+      Iir_Kind_External_Signal_Name => 1581,
+      Iir_Kind_External_Variable_Name => 1590,
+      Iir_Kind_Package_Pathname => 1593,
+      Iir_Kind_Absolute_Pathname => 1594,
+      Iir_Kind_Relative_Pathname => 1595,
+      Iir_Kind_Pathname_Element => 1599,
+      Iir_Kind_Base_Attribute => 1601,
+      Iir_Kind_Left_Type_Attribute => 1606,
+      Iir_Kind_Right_Type_Attribute => 1611,
+      Iir_Kind_High_Type_Attribute => 1616,
+      Iir_Kind_Low_Type_Attribute => 1621,
+      Iir_Kind_Ascending_Type_Attribute => 1626,
+      Iir_Kind_Image_Attribute => 1632,
+      Iir_Kind_Value_Attribute => 1638,
+      Iir_Kind_Pos_Attribute => 1644,
+      Iir_Kind_Val_Attribute => 1650,
+      Iir_Kind_Succ_Attribute => 1656,
+      Iir_Kind_Pred_Attribute => 1662,
+      Iir_Kind_Leftof_Attribute => 1668,
+      Iir_Kind_Rightof_Attribute => 1674,
+      Iir_Kind_Delayed_Attribute => 1682,
+      Iir_Kind_Stable_Attribute => 1690,
+      Iir_Kind_Quiet_Attribute => 1698,
+      Iir_Kind_Transaction_Attribute => 1706,
+      Iir_Kind_Event_Attribute => 1710,
+      Iir_Kind_Active_Attribute => 1714,
+      Iir_Kind_Last_Event_Attribute => 1718,
+      Iir_Kind_Last_Active_Attribute => 1722,
+      Iir_Kind_Last_Value_Attribute => 1726,
+      Iir_Kind_Driving_Attribute => 1730,
+      Iir_Kind_Driving_Value_Attribute => 1734,
+      Iir_Kind_Behavior_Attribute => 1734,
+      Iir_Kind_Structure_Attribute => 1734,
+      Iir_Kind_Simple_Name_Attribute => 1741,
+      Iir_Kind_Instance_Name_Attribute => 1746,
+      Iir_Kind_Path_Name_Attribute => 1751,
+      Iir_Kind_Left_Array_Attribute => 1758,
+      Iir_Kind_Right_Array_Attribute => 1765,
+      Iir_Kind_High_Array_Attribute => 1772,
+      Iir_Kind_Low_Array_Attribute => 1779,
+      Iir_Kind_Length_Array_Attribute => 1786,
+      Iir_Kind_Ascending_Array_Attribute => 1793,
+      Iir_Kind_Range_Array_Attribute => 1800,
+      Iir_Kind_Reverse_Range_Array_Attribute => 1807,
+      Iir_Kind_Attribute_Name => 1815
      );
 
    function Get_Fields (K : Iir_Kind) return Fields_Array
@@ -4968,6 +4974,8 @@ package body Nodes_Meta is
             return Get_Selected_Name (N);
          when Field_Type_Declarator =>
             return Get_Type_Declarator (N);
+         when Field_Associated_Type =>
+            return Get_Associated_Type (N);
          when Field_Entity_Class_Entry_Chain =>
             return Get_Entity_Class_Entry_Chain (N);
          when Field_Unit_Chain =>
@@ -5344,6 +5352,8 @@ package body Nodes_Meta is
             Set_Selected_Name (N, V);
          when Field_Type_Declarator =>
             Set_Type_Declarator (N, V);
+         when Field_Associated_Type =>
+            Set_Associated_Type (N, V);
          when Field_Entity_Class_Entry_Chain =>
             Set_Entity_Class_Entry_Chain (N, V);
          when Field_Unit_Chain =>
@@ -7650,6 +7660,11 @@ package body Nodes_Meta is
       end case;
    end Has_Type_Declarator;
 
+   function Has_Associated_Type (K : Iir_Kind) return Boolean is
+   begin
+      return K = Iir_Kind_Interface_Type_Definition;
+   end Has_Associated_Type;
+
    function Has_Enumeration_Literal_List (K : Iir_Kind) return Boolean is
    begin
       return K = Iir_Kind_Enumeration_Type_Definition;
diff --git a/src/vhdl/nodes_meta.ads b/src/vhdl/nodes_meta.ads
index c9fe6e695..c31d87ea7 100644
--- a/src/vhdl/nodes_meta.ads
+++ b/src/vhdl/nodes_meta.ads
@@ -180,6 +180,7 @@ package Nodes_Meta is
       Field_Context_Reference_Chain,
       Field_Selected_Name,
       Field_Type_Declarator,
+      Field_Associated_Type,
       Field_Enumeration_Literal_List,
       Field_Entity_Class_Entry_Chain,
       Field_Group_Constituent_List,
@@ -673,6 +674,7 @@ package Nodes_Meta is
    function Has_Context_Reference_Chain (K : Iir_Kind) return Boolean;
    function Has_Selected_Name (K : Iir_Kind) return Boolean;
    function Has_Type_Declarator (K : Iir_Kind) return Boolean;
+   function Has_Associated_Type (K : Iir_Kind) return Boolean;
    function Has_Enumeration_Literal_List (K : Iir_Kind) return Boolean;
    function Has_Entity_Class_Entry_Chain (K : Iir_Kind) return Boolean;
    function Has_Group_Constituent_List (K : Iir_Kind) return Boolean;
diff --git a/src/vhdl/sem.adb b/src/vhdl/sem.adb
index 08c3a7a8b..66e81d135 100644
--- a/src/vhdl/sem.adb
+++ b/src/vhdl/sem.adb
@@ -431,7 +431,8 @@ package body Sem is
             when Iir_Kind_Association_Element_Open
               | Iir_Kind_Association_Element_By_Individual
               | Iir_Kind_Association_Element_Package
-              | Iir_Kind_Association_Element_Type =>
+              | Iir_Kind_Association_Element_Type
+              | Iir_Kind_Association_Element_Subprogram =>
                null;
             when others =>
                Error_Kind ("sem_generic_association_chain(1)", El);
diff --git a/src/vhdl/sem_assocs.adb b/src/vhdl/sem_assocs.adb
index a56840df0..19ba3de92 100644
--- a/src/vhdl/sem_assocs.adb
+++ b/src/vhdl/sem_assocs.adb
@@ -39,6 +39,8 @@ package body Sem_Assocs is
             N_Assoc := Create_Iir (Iir_Kind_Association_Element_Package);
          when Iir_Kind_Interface_Type_Declaration =>
             N_Assoc := Create_Iir (Iir_Kind_Association_Element_Type);
+         when Iir_Kinds_Interface_Subprogram_Declaration =>
+            N_Assoc := Create_Iir (Iir_Kind_Association_Element_Subprogram);
          when others =>
             Error_Kind ("rewrite_non_object_association", Inter);
       end case;
@@ -1601,12 +1603,12 @@ package body Sem_Assocs is
       return Null_Iir;
    end Sem_Implicit_Operator_Association;
 
-   procedure Sem_Association_Type
-     (Assoc : Iir;
-      Inter : Iir;
-      Finish : Boolean;
-      Match : out Compatibility_Level)
+   procedure Sem_Association_Type (Assoc : Iir;
+                                   Inter : Iir;
+                                   Finish : Boolean;
+                                   Match : out Compatibility_Level)
    is
+      Inter_Def : constant Iir := Get_Type (Inter);
       Actual : Iir;
       Op_Eq, Op_Neq : Iir;
    begin
@@ -1626,6 +1628,10 @@ package body Sem_Assocs is
       Actual := Sem_Types.Sem_Subtype_Indication (Actual);
       Set_Actual (Assoc, Actual);
 
+      --  Set type association for analysis of reference to this interface.
+      pragma Assert (Is_Null (Get_Associated_Type (Inter_Def)));
+      Set_Associated_Type (Inter_Def, Get_Type (Actual));
+
       --  FIXME: it is not clear at all from the LRM how the implicit
       --  associations are done...
       Op_Eq := Sem_Implicit_Operator_Association
@@ -1638,6 +1644,178 @@ package body Sem_Assocs is
       end if;
    end Sem_Association_Type;
 
+   function Has_Interface_Subprogram_Profile
+     (Inter : Iir;
+      Decl : Iir;
+      Explain_Loc : Location_Type := No_Location) return Boolean
+   is
+      --  Handle previous assocation of interface type before full
+      --  instantiation.
+      function Get_Inter_Type (Inter : Iir) return Iir
+      is
+         Res : Iir;
+      begin
+         Res := Get_Type (Inter);
+         if Get_Kind (Res) = Iir_Kind_Interface_Type_Definition then
+            --  FIXME: recurse ?
+            return Get_Associated_Type (Res);
+         else
+            return Res;
+         end if;
+      end Get_Inter_Type;
+
+      Explain : constant Boolean := Explain_Loc /= No_Location;
+      El_Inter, El_Decl : Iir;
+   begin
+      case Iir_Kinds_Interface_Subprogram_Declaration (Get_Kind (Inter)) is
+         when Iir_Kind_Interface_Function_Declaration =>
+            if not Is_Function_Declaration (Decl) then
+               if Explain then
+                  Error_Msg_Sem (Explain_Loc, " actual is not a function");
+               end if;
+               return False;
+            end if;
+            if Get_Base_Type (Get_Inter_Type (Inter))
+              /= Get_Base_Type (Get_Type (Decl))
+            then
+               if Explain then
+                  Error_Msg_Sem (Explain_Loc, " return type doesn't match");
+               end if;
+               return False;
+            end if;
+         when Iir_Kind_Interface_Procedure_Declaration =>
+            if not Is_Procedure_Declaration (Decl) then
+               if Explain then
+                  Error_Msg_Sem (Explain_Loc, " actual is not a procedure");
+               end if;
+               return False;
+            end if;
+      end case;
+
+      El_Inter := Get_Interface_Declaration_Chain (Inter);
+      El_Decl := Get_Interface_Declaration_Chain (Decl);
+      loop
+         exit when Is_Null (El_Inter) and Is_Null (El_Decl);
+         if Is_Null (El_Inter) or Is_Null (El_Decl) then
+            if Explain then
+               Error_Msg_Sem
+                 (Explain_Loc, " number of interfaces doesn't match");
+            end if;
+            return False;
+         end if;
+         if Get_Base_Type (Get_Inter_Type (El_Inter))
+           /= Get_Base_Type (Get_Type (El_Decl))
+         then
+            if Explain then
+               Error_Msg_Sem
+                 (Explain_Loc,
+                  " type of interface %i doesn't match", +El_Inter);
+            end if;
+            return False;
+         end if;
+         El_Inter := Get_Chain (El_Inter);
+         El_Decl := Get_Chain (El_Decl);
+      end loop;
+
+      return True;
+   end Has_Interface_Subprogram_Profile;
+
+   procedure Sem_Association_Subprogram (Assoc : Iir;
+                                         Inter : Iir;
+                                         Finish : Boolean;
+                                         Match : out Compatibility_Level)
+   is
+      Discard : Boolean;
+      pragma Unreferenced (Discard);
+      Actual : Iir;
+      Res : Iir;
+   begin
+      if not Finish then
+         Sem_Association_Package_Type_Not_Finish (Assoc, Inter, Match);
+         return;
+      end if;
+
+      Match := Fully_Compatible;
+      Sem_Association_Package_Type_Finish (Assoc, Inter);
+      Actual := Get_Actual (Assoc);
+
+      --  LRM08 6.5.7.2 Generic map aspects
+      --  An actual associated with a formal generic subprogram shall be a name
+      --  that denotes a subprogram whose profile conforms to that of the
+      --  formal, or the reserved word OPEN.  The actual, if a predefined
+      --  attribute name that denotes a function, shall be one of the
+      --  predefined attributes 'IMAGE, 'VALUE, 'POS, 'VAL, 'SUCC, 'PREV,
+      --  'LEFTOF, or 'RIGHTOF.
+      Sem_Name (Actual);
+      Res := Get_Named_Entity (Actual);
+
+      if Is_Error (Res) then
+         return;
+      end if;
+
+      case Get_Kind (Res) is
+         when Iir_Kinds_Subprogram_Declaration
+           | Iir_Kinds_Interface_Subprogram_Declaration =>
+            if not Has_Interface_Subprogram_Profile (Inter, Res) then
+               Error_Msg_Sem
+                 (+Assoc, "profile of %n doesn't match profile of %n",
+                  (+Actual, +Inter));
+               Discard := Has_Interface_Subprogram_Profile
+                 (Inter, Res, Get_Location (Assoc));
+            end if;
+         when Iir_Kind_Overload_List =>
+            declare
+               First_Error : Boolean;
+               List : Iir_List;
+               El, R : Iir;
+            begin
+               First_Error := True;
+               R := Null_Iir;
+               List := Get_Overload_List (Res);
+               for I in Natural loop
+                  El := Get_Nth_Element (List, I);
+                  exit when El = Null_Iir;
+                  if Has_Interface_Subprogram_Profile (Inter, El) then
+                     if Is_Null (R) then
+                        R := El;
+                     else
+                        if First_Error then
+                           Error_Msg_Sem
+                             (+Assoc,
+                              "many possible actual subprogram for %n:",
+                              +Inter);
+                           Error_Msg_Sem
+                             (+Assoc, " %n declared at %l", (+R, + R));
+                           First_Error := False;
+                        else
+                           Error_Msg_Sem
+                             (+Assoc, " %n declared at %l", (+El, +El));
+                        end if;
+                     end if;
+                  end if;
+               end loop;
+               if Is_Null (R) then
+                  Error_Msg_Sem
+                    (+Assoc, "no matching name for %n", +Inter);
+                  if True then
+                     Error_Msg_Sem
+                       (+Assoc, " these names were incompatible:");
+                     for I in Natural loop
+                        El := Get_Nth_Element (List, I);
+                        exit when El = Null_Iir;
+                        Error_Msg_Sem
+                          (+Assoc, " %n declared at %l", (+El, +El));
+                     end loop;
+                  end if;
+               end if;
+               Free_Overload_List (Res);
+               Set_Named_Entity (Actual, R);
+            end;
+         when others =>
+            Error_Kind ("sem_association_subprogram", Res);
+      end case;
+   end Sem_Association_Subprogram;
+
    --  Associate ASSOC with interface INTERFACE
    --  This sets MATCH.
    procedure Sem_Association_By_Expression
@@ -1872,14 +2050,17 @@ package body Sem_Assocs is
          when Iir_Kind_Association_Element_Open =>
             Sem_Association_Open (Assoc, Inter, Finish, Match);
 
+         when Iir_Kind_Association_Element_By_Expression =>
+            Sem_Association_By_Expression (Assoc, Inter, Finish, Match);
+
          when Iir_Kind_Association_Element_Package =>
             Sem_Association_Package (Assoc, Inter, Finish, Match);
 
          when Iir_Kind_Association_Element_Type =>
             Sem_Association_Type (Assoc, Inter, Finish, Match);
 
-         when Iir_Kind_Association_Element_By_Expression =>
-            Sem_Association_By_Expression (Assoc, Inter, Finish, Match);
+         when Iir_Kind_Association_Element_Subprogram =>
+            Sem_Association_Subprogram (Assoc, Inter, Finish, Match);
 
          when others =>
             Error_Kind ("sem_assocation", Assoc);
@@ -2173,6 +2354,12 @@ package body Sem_Assocs is
                   Error_Kind ("sem_association_chain", Inter);
             end case;
          end if;
+
+         --  Clear associated type of interface type.
+         if Get_Kind (Inter) = Iir_Kind_Interface_Type_Declaration then
+            Set_Associated_Type (Get_Type (Inter), Null_Iir);
+         end if;
+
          Inter := Get_Chain (Inter);
          Pos := Pos + 1;
       end loop;
diff --git a/src/vhdl/sem_decls.adb b/src/vhdl/sem_decls.adb
index 7cf490249..3fd25927e 100644
--- a/src/vhdl/sem_decls.adb
+++ b/src/vhdl/sem_decls.adb
@@ -456,6 +456,7 @@ package body Sem_Decls is
    procedure Sem_Interface_Chain (Interface_Chain: Iir;
                                   Interface_Kind : Interface_Kind_Type)
    is
+      --  Control visibility of interface object.  See below for its use.
       Immediately_Visible : constant Boolean :=
         Interface_Kind = Generic_Interface_List
         and then Flags.Vhdl_Std >= Vhdl_08;
@@ -484,6 +485,10 @@ package body Sem_Decls is
          end case;
 
          --  LRM08 6.5.6 Interface lists
+         --  A name that denotes an interface object declared in a port
+         --  interface list of a prameter interface list shall not appear in
+         --  any interface declaration within the interface list containing the
+         --  denoted interface object expect to declare this object.
          --  A name that denotes an interface declaration in a generic
          --  interface list may appear in an interface declaration within the
          --  interface list containing the denoted interface declaration.
@@ -3136,7 +3141,8 @@ package body Sem_Decls is
                   end if;
                end;
             when Iir_Kind_Package_Declaration =>
-               if Get_Need_Body (El)
+               if Is_Null (Get_Package_Origin (El))
+                 and then Get_Need_Body (El)
                  and then Get_Package_Body (El) = Null_Iir
                then
                   Error_Msg_Sem (+El, "missing package body for %n", +El);
diff --git a/src/vhdl/sem_inst.adb b/src/vhdl/sem_inst.adb
index 597010b62..20841263b 100644
--- a/src/vhdl/sem_inst.adb
+++ b/src/vhdl/sem_inst.adb
@@ -402,6 +402,9 @@ package body Sem_Inst is
                      Set_Subprogram_Body (Spec, Res);
                   end;
 
+               when Field_Incomplete_Type_List =>
+                  null;
+
                when others =>
                   --  Common case.
                   Instantiate_Iir_Field (Res, N, F);
@@ -410,6 +413,7 @@ package body Sem_Inst is
 
          --  TODO: other forward references:
          --  incomplete constant
+         --  incomplete type
          --  attribute_value
 
          return Res;
@@ -457,6 +461,8 @@ package body Sem_Inst is
                  (Res, Get_Uninstantiated_Package_Name (Inter));
             when Iir_Kind_Interface_Type_Declaration =>
                Set_Type (Res, Get_Type (Inter));
+            when Iir_Kinds_Interface_Subprogram_Declaration =>
+               null;
             when others =>
                Error_Kind ("instantiate_generic_chain", Res);
          end case;
@@ -662,6 +668,16 @@ package body Sem_Inst is
                begin
                   Set_Instance (Inter_Type_Def, Actual_Type);
                end;
+            when Iir_Kind_Association_Element_Subprogram =>
+               --  Replace the interface subprogram by the subprogram.
+               declare
+                  Inter_Subprg : constant Iir :=
+                    Get_Association_Interface (Assoc, Inter);
+                  Actual_Subprg : constant Iir :=
+                    Get_Named_Entity (Get_Actual (Assoc));
+               begin
+                  Set_Instance (Get_Origin (Inter_Subprg), Actual_Subprg);
+               end;
             when others =>
                Error_Kind ("instantiate_generic_map_chain", Assoc);
          end case;
@@ -759,7 +775,7 @@ package body Sem_Inst is
                   begin
                      Imp_Assoc := Get_Subprogram_Association_Chain (Inst_El);
                      Imp_Inter := Get_Interface_Type_Subprograms
-                       (Get_Origin (Inter_El));
+                       (Get_Origin (Inter));
                      while Is_Valid (Imp_Inter) and Is_Valid (Imp_Assoc) loop
                         Set_Instance
                           (Imp_Inter,
diff --git a/src/vhdl/translate/trans-chap4.adb b/src/vhdl/translate/trans-chap4.adb
index ca0bff60b..fa1a09843 100644
--- a/src/vhdl/translate/trans-chap4.adb
+++ b/src/vhdl/translate/trans-chap4.adb
@@ -1631,7 +1631,8 @@ package body Trans.Chap4 is
                Create_Object (Decl);
             when Iir_Kind_Interface_Package_Declaration =>
                Create_Package_Interface (Decl);
-            when Iir_Kind_Interface_Type_Declaration =>
+            when Iir_Kind_Interface_Type_Declaration
+              | Iir_Kinds_Interface_Subprogram_Declaration =>
                null;
             when others =>
                Error_Kind ("translate_generic_chain", Decl);
diff --git a/src/vhdl/translate/trans-chap5.adb b/src/vhdl/translate/trans-chap5.adb
index cc5f349d0..c86f34602 100644
--- a/src/vhdl/translate/trans-chap5.adb
+++ b/src/vhdl/translate/trans-chap5.adb
@@ -802,7 +802,8 @@ package body Trans.Chap5 is
                             (Actual_Info.Package_Instance_Body_Scope),
                         Uninst_Info.Package_Body_Ptr_Type));
                end;
-            when Iir_Kind_Association_Element_Type =>
+            when Iir_Kind_Association_Element_Type
+              | Iir_Kind_Association_Element_Subprogram =>
                null;
             when others =>
                Error_Kind ("elab_generic_map_aspect(1)", Assoc);