t / t4018 / perl-skip-sub-in-podon commit git-compat-util.h: don't define _XOPEN_SOURCE on cygwin (3a0a3a8)
   1=head1 NAME
   2
   3Beer - subroutine to output fragment of a drinking song
   4
   5=head1 SYNOPSIS_RIGHT
   6
   7        use Beer qw(round finalround);
   8
   9        sub song {
  10                for (my $i = 99; $i > 0; $i--) {
  11                        round $i;
  12                }
  13                finalround;
  14        }
  15
  16        ChangeMe;
  17
  18=cut