[Mesa-dev] Rust drivers in Mesa

[Thomas Zimmermann]

Hi

On Tue, 13 Oct 2020 13:01:58 -0700 Eric Anholt <eric at anholt.net> wrote:

> On Tue, Oct 13, 2020 at 12:08 AM Thomas Zimmermann <tzimmermann at suse.de>
> wrote:
> >
> > Hi
> >
> > On Fri, 02 Oct 2020 08:04:43 -0700 "Dylan Baker" <dylan at pnwbakers.com>
> > wrote:
> >
> > > I have serious concerns about cargo and crate usage. Cargo is basically
> > > npm for rust, and shares all of the bad design decisions of npm,
> > > including linking multiple versions of the same library together and
> > > ballooning dependency lists that are fetched intrigued from the
> > > internet. This is both a security problem and directly in conflict with
> > > meson's design off one and only one version of a project. And while
> > > rust prevents certain kinds of bugs, it doesn't prevent design bugs or
> > > malicious code. Add a meson developer the rust community has been
> > > incredibly hard to work with and basically hostile to every request
> > > we've made "cargo is hour you build rust", is essentially the answer
> > > we've gotten from them at every turn. And if you're not going to use
> > > cargo, is rust really a win? The standard library is rather minimal
> > > "because just pull in 1000 crates". The distro people can correct me if
> > > I'm wrong, but when librsvg went to rust it was a nightmare, several
> > > distros went a long time without u
> >  pdates because of cargo.
> >
> > I can't say much about meson, but using Rust has broken the binaries of
> > several packages on i586 for us; which consequently affects Gnome and KDE.
> > [1][2] Rust uses SSE2 instructions on platforms that don't have them.
> > There's a proposed workaround, but it's not yet clear if that's feasible
> > in practice.
> >
> > Best regards
> > Thomas
> >
> > [1] https://bugzilla.opensuse.org/show_bug.cgi?id=1162283
> > [2] https://bugzilla.opensuse.org/show_bug.cgi?id=1077870
> 
> From the first bug:
> 
> >Not entirely sure what to do about this. i586 is unsupported by Rust (tier
> >2) and as such the package is built for i686
> 
> This really sounds like your distro is just building with the wrong
> rust target for packages targeting an earlier processor.

Every other language/compiler combination appears to get this right. And even
i686 does not require SSE2. As I said before, there might be a
workaround.

Best regards
Thomas

Thomas