vhdl: avoid crash on incorrect unit name.

Fix #886

2 files changed, 36 insertions, 6 deletions

diff --git a/src/vhdl/vhdl-parse.adb b/src/vhdl/vhdl-parse.adb
index 7e15589df..8800da259 100644
--- a/src/vhdl/vhdl-parse.adb
+++ b/src/vhdl/vhdl-parse.adb
@@ -5513,6 +5513,26 @@ package body Vhdl.Parse is
       end if;
    end Resize_Bit_String;
 
+   --  LRM93 3.1.3
+   --  /unit/_name
+   --
+   --  A unit name is a name, but it must designate a unit declaration.  As
+   --  a consequence, it can only be a simple_name or a selected name.
+   function Parse_Unit_Name return Iir
+   is
+      Res : Iir;
+   begin
+      Res := Parse_Name (Allow_Indexes => False);
+      case Get_Kind (Res) is
+         when Iir_Kind_Simple_Name
+           | Iir_Kind_Selected_Name =>
+            null;
+         when others =>
+            Error_Msg_Parse ("invalid unit name");
+      end case;
+      return Res;
+   end Parse_Unit_Name;
+
    --  Precond : next token after tok_integer
    --  postcond: likewise
    --
@@ -5524,7 +5544,7 @@ package body Vhdl.Parse is
       if Current_Token = Tok_Identifier then
          -- physical literal
          Res := Create_Iir (Iir_Kind_Physical_Int_Literal);
-         Set_Unit_Name (Res, Parse_Name (Allow_Indexes => False));
+         Set_Unit_Name (Res, Parse_Unit_Name);
       else
          -- integer literal
          Res := Create_Iir (Iir_Kind_Integer_Literal);
@@ -5595,7 +5615,7 @@ package body Vhdl.Parse is
             if Current_Token = Tok_Identifier then
                -- physical literal
                Res := Create_Iir (Iir_Kind_Physical_Fp_Literal);
-               Set_Unit_Name (Res, Parse_Name (Allow_Indexes => False));
+               Set_Unit_Name (Res, Parse_Unit_Name);
             else
                -- real literal
                Res := Create_Iir (Iir_Kind_Floating_Point_Literal);
diff --git a/src/vhdl/vhdl-sem_expr.adb b/src/vhdl/vhdl-sem_expr.adb
index 418d3534f..e579aef83 100644
--- a/src/vhdl/vhdl-sem_expr.adb
+++ b/src/vhdl/vhdl-sem_expr.adb
@@ -4016,10 +4016,20 @@ package body Vhdl.Sem_Expr is
          return Create_Error_Expr (Res, Error_Mark);
       end if;
 
-      Unit_Name := Sem_Denoting_Name (Unit_Name);
-      Unit := Get_Named_Entity (Unit_Name);
-      if Get_Kind (Unit) /= Iir_Kind_Unit_Declaration then
-         if not Is_Error (Unit) then
+      case Get_Kind (Unit_Name) is
+         when Iir_Kind_Simple_Name
+           | Iir_Kind_Selected_Name =>
+            Unit_Name := Sem_Denoting_Name (Unit_Name);
+            Unit := Get_Named_Entity (Unit_Name);
+         when others =>
+            pragma Assert (Flags.Flag_Force_Analysis);
+            Unit := Null_Iir;
+      end case;
+
+      if Unit = Null_Iir
+        or else Get_Kind (Unit) /= Iir_Kind_Unit_Declaration
+      then
+         if Unit /= Null_Iir and then not Is_Error (Unit) then
             Error_Class_Match (Unit_Name, "unit");
          end if;
          Set_Named_Entity (Unit_Name, Create_Error_Name (Unit_Name));