-- { dg-do run } -- { dg-options "-O" } with System; use System; procedure Boolean_Bitfield is Units_Per_Integer : constant := (Integer'Size + System.Storage_Unit - 1) / System.Storage_Unit; type E_type is (Red, Blue, Green); type Parent_Type is record I : Integer range 0 .. 127 := 127; C : Character := 'S'; B : Boolean := False; E : E_Type := Blue; end record; for Parent_Type use record C at 0 * Units_Per_Integer range 0 .. Character'Size - 1; B at 1 * Units_Per_Integer range 0 .. Boolean'Size - 1; I at 2 * Units_Per_Integer range 0 .. Integer'Size/2 - 1; E at 3 * Units_Per_Integer range 0 .. Character'Size - 1; end record; type Derived_Type is new Parent_Type; for Derived_Type use record C at 1 * Units_Per_Integer range 1 .. Character'Size + 1; B at 3 * Units_Per_Integer range 1 .. Boolean'Size + 1; I at 5 * Units_Per_Integer range 1 .. Integer'Size/2 + 1; E at 7 * Units_Per_Integer range 1 .. Character'Size + 1; end record; Rec : Derived_Type; begin Rec := (12, 'T', True, Red); if (Rec.I /= 12) or (Rec.C /= 'T') or (not Rec.B) or (Rec.E /= Red) then raise Program_Error; end if; end;