Re: Lancaster Consensus, deal with PUREPERL_ONLY=0

Am 02.06.2014 um 13:34 schrieb David Golden <[email protected]>:

> On Mon, Jun 2, 2014 at 7:28 AM, Jens Rehsack <[email protected]> wrote:
>> Others (eg. packagers) have always a compiler and want benefit from XS when
>> available and what is more important: if the "DEVELOPER MODE FLAGS IS ON",
>> they want to have a -Werror behavior even for "I enabled foo and it doesn't
>> appear".
> 
> I don't understand what you mean by this.

http://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html

It's the widest know of those flags - GNU autotools provide such a one, too.
xlc names it -qhalt=<severity> ...

Lot's of tools provide switches which exit when something doesn't do as
wanted (if a specific behavior is intended).

>> I'm fine with "Jens' distribution have a non-standard switch", but I
>> would prefer a "Toolchain community favors that knob to be used".
> 
> In Lancaster, we considered having both a "give me PP" option *and* a
> "give me XS" option and the group decided it was less confusing to
> have just one.

I didn't had the "user control > author mind" situation. I evolved by
implementing (both sides - provide CPAN distributions and use/package
them).

> Here's how I would do it:
> 
> (a) if the PP option is there, give them PP
> (b) if the PP option is missing/false, check if there is a compiler
> (c) if there is a compiler, give them XS or give them death
> (d) if there isn't a compiler, give them PP
> 
> If for (c) that means running tests under some "XS-only" flag of your
> own, that's fine with me.

(b)-(d) shall die (or exit 0 in Makefile.PL) when XS-force flag is set.

I currently prove:
a) what is wanted (tri-state: PP-only, XS-only, check)
pp-b) do just pp
b) check for "sane xs" (perl.h, xsub.h, perl-api, ...)
xs-c) (b) or bail-out
check-c) (b) or goto (pp-b)
d) compile && pp

Is that somehow clear?

But ... that brings me to another point of view. Take Unix::Statgrab,
File::LibMagic or BSD::Resource as example - they won't work without XS
either. Shall they generally bail-out when PUREPERL_ONLY=1 is set?

Cheers
-- 
Jens Rehsack
[email protected]