type LongestWord = LongestCard;
LongestWord is GPC's longest-possible unsigned integer type. Currently, this is the same as LongWord. On some platforms it is 64 bits wide and thus has a range of 0 .. 18446744073709551615. (It is the same as LongestCard.)
There are lots of other integer types in GPC, see Integer Types.
LongestWord is a GNU Pascal extension.
program LongestWordDemo; var a: LongestWord; begin a := 42; WriteLn (a) end.
LongestCard, Integer Types, Subrange Types.