Re: Lancaster Consensus, deal with PUREPERL_ONLY=0

Am 04.06.2014 um 04:32 schrieb David Golden <[email protected]>:

> On Tue, Jun 3, 2014 at 1:35 AM, Jens Rehsack <[email protected]> wrote:
>> 1) compiler cannot create executables
>> 2) compiler works, but no perl headers
>> 3) compiler does, but shared library building fails (that is fragile and minor modifications at the system causes that process to fail)
> 
> These three would all fail to make, which would abort installation.
> 
>> 4) As you say: https://rt.cpan.org/Ticket/Display.html?id=75672
> 
> Oooh!  Excellent example.
> 
> "make" succeeds and "make test" could fall back to PP when dynaloading fails.
> 
> I wonder if there's a way to be clever about this such that under
> PUREPERL_ONLY, make never compiles the extension, and then the main
> module doesn't just try bootstrap inside eval{} but actually checks to
> see if the extension is in @INC. If so, bootstrap it or die; if not,
> fall back to pure Perl.

talked yesterday with riba about that in deeper detail.
We decided to do as (probably) suggested by you and

sub legacy_exists { die "bogus legacy XS" if the extension is in @INC; return false }

autoconf->check_pp_wanted and return legacy_exists;
autoconf->have_compiler or return legacy_exists;
autoconf->check_perl_api or die;
if( autoconf->extensive_testing ) {
  autoconf->check_perl_extension_links or die;
  autoconf->check_perl_extension_loads or die;
}
return ok

http://www.cpantesters.org/cpan/report/a25a36da-ea1d-11e3-9cf0-a01f06268b4b is also an excellent example.

Regarding "if the extension is in @INC" (have separate installed XS module) needs a migration plan for LMU, P::U etc.
This is the final solution and we had several ideas yesterday for a migration plan - but wasn't complete.

Cheers
-- 
Jens Rehsack
[email protected]