1 files changed, 4 insertions, 0 deletions
diff --git a/src/vhdl/vhdl-sem_types.adb b/src/vhdl/vhdl-sem_types.adb
index f4f142f6a..2c0d54636 100644
--- a/src/vhdl/vhdl-sem_types.adb
+++ b/src/vhdl/vhdl-sem_types.adb
@@ -2401,6 +2401,10 @@ package body Vhdl.Sem_Types is
             Free_Name (Def);
             return Type_Mark;
 
+         when Iir_Kind_Interface_Type_Definition =>
+            Error_Msg_Sem (+Def, "interface types can't be constrained");
+            return Type_Mark;
+
          when Iir_Kind_Error =>
             return Type_Mark;