# from perl

sub do_nothing {
  my $doubles = pack 'd*', @_;
  _do_nothing_c($doubles);
  return unpack 'd*', $doubles;
}


# from XS

void
_do_nothing_c(sv)
  SV *sv
PREINIT:
  STRLEN len;
  char *pv;
CODE:
  pv = SvPV_force(sv, len);
  do_nothing((double *)pv, len / sizeof(double));