An alternative approach is to pack and unpack the array from the Perl side: 
# 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));

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In reply to Re: perl XS - passing array to C and getting it back by salva
in thread perl XS - passing array to C and getting it back by kopolov

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