type
       LongestBool = Boolean attribute (Size = BitSizeOf (LongestInt));
The intrinsic LongestBool represents boolean values, but occupies the same memory space as a LongestInt. It is used when you need to define a parameter or record that conforms to some external library or system specification.
LongestBool is a GNU Pascal extension.
     program LongestBoolDemo;
     var
       a: LongestBool;
     begin
       LongestInt (a) := 1;
       if a then WriteLn ('Ord (True) = 1')
     end.
Boolean (Intrinsic), Boolean, True, False, CBoolean, ByteBool, ShortBool, MedBool, WordBool, LongBool.