%---------------------------------------------------------------------------%
% vim: ts=4 sw=4 et ft=mercury
%---------------------------------------------------------------------------%

:- module foreign_underscore_var.

:- interface.

:- import_module io.

:- pred main(io::di, io::uo) is det.

:- implementation.

main -->
   f(X),
   io__write_int(X),
   io__nl.

:- pred f(int::out, io::di, io::uo) is det.

:- pragma foreign_proc("C",
    f(X::out, _IO0::di, _IO::uo),
    [will_not_call_mercury, promise_pure],
"
    X = 5;
").

f(5) --> [].