[Python-ideas] CPython needs to revamp/replace it's build system && Cross-compiling Python sucks

[Nick Coghlan]

On 14 Mar 2015 04:05, "Ryan Gonzalez" <rymg19 at gmail.com> wrote:
>
> If C99's ok, there's hope. :)

As far as I can recall, the main culprit there in relation to CPython
itself has long been MSVC's lack of support for C99, but the very fact we
use the native build chain on Windows means it isn't relevant to the choice
of build system on other platforms.

I may have forgotten another reason for the C89 requirement, but if I'm
right then a build tool for non-Windows systems could potentially be
allowed to require C99 support.

Regards,
Nick.

>
> C++'s main issue is that there are platforms that support C99 but have
out-of-date or non-complaint C++ compilers. I love the language (yes, I'm
weird), but it's tricky to have truly portable C++ programs because if all
the holes in various compilers. Just look at all the #ifdef's in Boost.
>
> On Fri, Mar 13, 2015 at 7:15 AM, Nick Coghlan <ncoghlan at gmail.com> wrote:
>>
>> On 12 March 2015 at 04:30, Ryan Gonzalez <rymg19 at gmail.com> wrote:
>> > On Wed, Mar 11, 2015 at 10:07 AM, Brett Cannon <brett at python.org>
wrote:
>> >>
>> >>
>> >>
>> >> On Tue, Mar 10, 2015 at 11:40 AM Ryan Gonzalez <rymg19 at gmail.com>
wrote:
>> >>>
>> >>> On Tue, Mar 10, 2015 at 8:43 AM, Nick Coghlan <ncoghlan at gmail.com>
wrote:
>> >>>>
>> >>>> On 10 March 2015 at 21:20, Russell Keith-Magee <
russell at keith-magee.com>
>> >>>> wrote:
>> >>>> >
>> >>>> > On Tue, Mar 10, 2015 at 10:43 AM, Ryan <rymg19 at gmail.com> wrote:
>> >>>> >>
>> >>>> >> Russell Keith-Magee <russell at keith-magee.com> wrote:
>> >>>> >> >Hi Ryan,
>> >>>> >> >
>> >>>> >> >First off I'm no fan of autoconf, but...
>> >>>> >> >
>> >>>> >>
>> >>>> >> Who is other than the one who designed it? :)
>> >>>> >
>> >>>> > Let me be clear - there's a difference between "not a fan" and
>> >>>> > "calling for
>> >>>> > it's head". Autoconf is crufty, annoying, and sometimes
aggravating -
>> >>>> > but it
>> >>>> > *works*, and has had some pretty seriously battle testing - both
in
>> >>>> > the
>> >>>> > abstract "autoconf as a product", and in the specific "autoconf as
>> >>>> > used in
>> >>>> > Python". This isn't something that can be said of most of the
>> >>>> > alternatives
>> >>>> > in the abstract case, or *any* of the alternatives in the Python
case.
>> >>>>
>> >>>> Building architecture dependent software is a genuinely hard
problem,
>> >>>> which is why it's full of "80%" solutions like autotools and the
>> >>>> setuptools/distutils pairing. Yes, they're quirky and annoying, but
>> >>>> they also basically do their job, so folks tend to develop a high
>> >>>> tolerance level for their quirks.
>> >>>>
>> >>>> In our particular case, we also have the fun problem of "How do you
>> >>>> build CPython locally when you don't have a working Python
interpreter
>> >>>> yet?". A number of the more interesting alternative C/C++ build
>> >>>> systems (like Meson, Scons, Waf and the Google "gyp" project that
>> >>>> powers the node-gyp native extension build system for Node.js)
require
>> >>>> an already working Python interpreter to get things started (when
>> >>>> starting from a completely blank slate, even our own build sequence
>> >>>> has to build a deliberately broken partial interpreter just to
freeze
>> >>>> importlib._bootstrap before going on to build a properly configured
>> >>>> one that can actually import modules).
>> >>>
>> >>>
>> >>> What about something like Google's new GN? It's designed to replace
Gyp
>> >>> in building Chromium and is written in C++.
>> >>>
>> >>> I'm pretty sure using a build system written in Lua to build Python
is
>> >>> kind of weird.
>> >>
>> >>
>> >>>
>> >>>
>> >>> With all that in mind...what exactly would be requirements that
Python
>> >>> would need in an autotools replacement?
>> >>
>> >>
>> >> Can't require anything more than an ANSI C compiler basically. People
run
>> >> Python in places where they don't have much more than gcc.
>> >
>> >
>> > Not even C99? Darn it...
>>
>> C99 would probably be OK these days. If there's a good enough
>> cross-compiling story, I'm also not sure we should entirely rule out
>> C++, as it's potentially OK if *developing* CPython requires a
>> mainstream platform with a C++ compiler.
>>
>> But yeah, you can see why folks look at this problem and end up
>> thinking "well, you know, maybe autotools isn't *that* bad..."
>>
>> Cheers,
>> Nick.
>>
>> --
>> Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia
>
>
>
>
> --
> Ryan
> [ERROR]: Your autotools build scripts are 200 lines longer than your
program. Something’s wrong.
> http://kirbyfan64.github.io/
>
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