[Mesa-dev] Drop scons for 20.1?

Fri Mar 27 13:29:45 UTC 2020

In the long term we should reduce the complexity of the project. scons is a maintenance burden.
We all agree here.  And we are making progress.  Even a couple of weeks ago I had to debug and fix weird Meson behaviour -- https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4186
 Every time I break the scons build and the CI reports it, can I politely ask you to fix my MR instead of me doing it? Then at least the real maintenance cost would be known to scons supporters, instead of the cost being invisible to most.
Sure.  But first I want all the time back I spent fixing scons and msvc builds when the cost was invisible to most.  Even after setting up Appveyor people ignored the successive build failures.  Even when fix was plain trivial and easily avoidable (like replacing non-standard `= {}`  initializers for `= { 0 }`).   Even when I politely asked to fix it, people ignored.  Not you perhaps, but several did.

Honestly, why do you blame me/us?  Mesa had multiple build systems for all its life -- all with different state of brokenness.   What really changed these days is not actually the Meson-holy-grail, but this new Marge-bot overlord.  Personally I find it this new process a tad too draconian.

If SCons is such a time sink, then the best we can do is suggest to take it off Marge-bot.  The onus of fixing SCons will go back to us, as it always did throughout these the past twelve years.

BTW, the grief you and others might be experiencing now, is probably 1/100th of what we systematically had throughout these years.  I particularly recall all the pain and grief to replicate all the autoconf build logic for code generation every time there was a major addition / refactoring in Mesa -- in particular all those Python scripts that generated C code are very difficult to match, because unlike Autoconf, SCons had fined grained dependencies, so missing one dependency meant incremental builds would use stale source code.  Some times there were more broken builds that good ones.  Even git-bisecting was extremely had as result.  Though to be fair, I do recall I also moaned and bitch about it too.
In the mean time, I think we can remove all parts of scons that VMWare does NOT care about. Do you need haiku-softpipe? Do you need graw-null? Do you need swr? glx? There is bunch you don't really need on Windows.
Now that is a more serious proposal.  An excellent one in fact.

The only scons targets we need are libgl-gdi (and its dependencies, including llvmpipe) and svga.

Everything else can go as far as we are concerned.  graw was useful at one point, but I don't think it's that useful anymore.  Regarding haiku-softpipe and swr targets, they were not added to SCons by VMware.  I suppose if the stakeholders didn't speak up so far, one can assume they don't care.

Jose

________________________________
From: Marek Olšák <maraeo at gmail.com>
Sent: Friday, March 27, 2020 00:56
To: Jose Fonseca <jfonseca at vmware.com>
Cc: Jason Ekstrand <jason at jlekstrand.net>; Rob Clark <robdclark at gmail.com>; Kristian Høgsberg <hoegsberg at gmail.com>; mesa-dev <mesa-dev at lists.freedesktop.org>; Dylan Baker <baker.dylan.c at gmail.com>
Subject: Re: [Mesa-dev] Drop scons for 20.1?

In the long term we should reduce the complexity of the project. scons is a maintenance burden. Every time I break the scons build and the CI reports it, can I politely ask you to fix my MR instead of me doing it? Then at least the real maintenance cost would be known to scons supporters, instead of the cost being invisible to most.

In the mean time, I think we can remove all parts of scons that VMWare does NOT care about. Do you need haiku-softpipe? Do you need graw-null? Do you need swr? glx? There is bunch you don't really need on Windows.

Marek

On Wed, Feb 26, 2020 at 3:44 PM Jose Fonseca <jfonseca at vmware.com<mailto:jfonseca at vmware.com>> wrote:
We already solved some pieces (e.g, how to consume and use Meson, while following our internal legal process required for adding new 3rd party dependencies), and figured a way to consume Meson build without having to migrate lots of internal build logic from Scons to Meson.  But other stuff just keeps getting higher priority, and we haven't fully migrated.

Please do understand, SCons just works for us.  We are making progress with Meson.  It's just not the highest priority, when time is short, it gets deferred.

I don't understand the rush.  If it was trivial and easy we'd obviously would have done it.

Jose

________________________________
From: Jason Ekstrand <jason at jlekstrand.net<mailto:jason at jlekstrand.net>>
Sent: Wednesday, February 26, 2020 04:15
To: Rob Clark <robdclark at gmail.com<mailto:robdclark at gmail.com>>; Kristian Høgsberg <hoegsberg at gmail.com<mailto:hoegsberg at gmail.com>>
Cc: mesa-dev <mesa-dev at lists.freedesktop.org<mailto:mesa-dev at lists.freedesktop.org>>; Dylan Baker <baker.dylan.c at gmail.com<mailto:baker.dylan.c at gmail.com>>; Jose Fonseca <jfonseca at vmware.com<mailto:jfonseca at vmware.com>>; Brian Paul <brianp at vmware.com<mailto:brianp at vmware.com>>
Subject: Re: [Mesa-dev] Drop scons for 20.1?

+Jose & Brian

I'm not personally opposed but I also can't remember the last time I had to
fix the scons build. I think it's been years. Maybe that's because I don't
work on GL anymore? In any case, I don't know that it's really costing us
that much given that basically none of the drivers actually build with it.
But fat meh, I guess.

--Jason

On February 25, 2020 21:56:30 Rob Clark <robdclark at gmail.com<mailto:robdclark at gmail.com>> wrote:

> It looks like we have 4 scons build jobs in CI.. I'm not sure how much
> that costs us, but I guess those cycles could be put to better use?
> So even ignoring the developer-cycles issue (ie. someone making
> changes that effects scons build, and has to setup a scons build env
> to fix breakage of their MR) I guess there is at least an argument to
> remove scons from CI.  Whether it is worth keeping a dead build system
> after it is removed from CI is an issue that I'm ambivalent about.
>
> BR,
> -R
>
> On Tue, Feb 25, 2020 at 3:42 PM Kristian Høgsberg <hoegsberg at gmail.com<mailto:hoegsberg at gmail.com>> wrote:
>>
>> It's been a while since Dylan did the work to make meson support
>> Windows and there's been plenty of time to provide feedback or improve
>> argue why we still need scons. I haven't seen any such discussion and
>> I think we've waited long enough.
>>
>> Let's drop scons for the next release and move things forward?
>>
>> Kristian
>> _______________________________________________
>> mesa-dev mailing list
>> mesa-dev at lists.freedesktop.org<mailto:mesa-dev at lists.freedesktop.org>
>> https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fmesa-dev&data=02%7C01%7Cjfonseca%40vmware.com%7Cc8b86d6f312c48d77f3c08d7ba72774f%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C637182873108493719&sdata=oKvqrkRoo6%2FqGW5BWbe1exIcBF%2BI%2BblcWIIVo3iW9J0%3D&reserved=0<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fmesa-dev&data=02%7C01%7Cjfonseca%40vmware.com%7C1e432c5661d74414562208d7d1e9c589%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C637208674291834362&sdata=zw1nv5uh2lwq6lde3CIbPYjXFjwx0462eKlgopEUZgk%3D&reserved=0>
> _______________________________________________
> mesa-dev mailing list
> mesa-dev at lists.freedesktop.org<mailto:mesa-dev at lists.freedesktop.org>
> https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fmesa-dev&data=02%7C01%7Cjfonseca%40vmware.com%7Cc8b86d6f312c48d77f3c08d7ba72774f%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C637182873108493719&sdata=oKvqrkRoo6%2FqGW5BWbe1exIcBF%2BI%2BblcWIIVo3iW9J0%3D&reserved=0<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fmesa-dev&data=02%7C01%7Cjfonseca%40vmware.com%7C1e432c5661d74414562208d7d1e9c589%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C637208674291844358&sdata=z7kuex5o8Pjn7PKJ1uk6wC1hhB1PbXXBioPYyGm7wvs%3D&reserved=0>

_______________________________________________
mesa-dev mailing list
mesa-dev at lists.freedesktop.org<mailto:mesa-dev at lists.freedesktop.org>
https://lists.freedesktop.org/mailman/listinfo/mesa-dev<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fmesa-dev&data=02%7C01%7Cjfonseca%40vmware.com%7C1e432c5661d74414562208d7d1e9c589%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C637208674291844358&sdata=z7kuex5o8Pjn7PKJ1uk6wC1hhB1PbXXBioPYyGm7wvs%3D&reserved=0>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/mesa-dev/attachments/20200327/cf584c91/attachment-0001.htm>