Re: librsvg & Rust

[ng0@n0.is]

Marius Bakke transcribed 2.7K bytes:
> Ludovic Courtès <ludo@gnu.org> writes:
> 
> > Hello Guix!
> >
> > guix-commits@gnu.org skribis:
> >
> >> mbakke pushed a commit to branch staging
> >> in repository guix.
> >>
> >> commit ec47c07d0690653be35a75b346f3c3548a3e71d4
> >> Author: Marius Bakke <mbakke@fastmail.com>
> >> Date:   Wed Oct 24 15:26:10 2018 +0200
> >>
> >>     gnu: librsvg: Update to 2.44.12.
> >>     
> >>     * gnu/packages/gnome.scm (librsvg): Update to 2.44.12.
> >>     [arguments]: Replace patching phases with custom variants.  Delete five new
> >>     tests.
> >>     [native-inputs]: Add RUST-1.27 and RUST-1.27:CARGO.
> >
> > This change was bound to happen since upstream switched to Rust, but
> > it creates a few issues.
> >
> > First, that adds Rust to the base graphical applications, which
> > significantly increases build times and size:
> >
> > --8<---------------cut here---------------start------------->8---
> > $ guix size librsvg | tail -1
> > total: 207.2 MiB
> > $ guix size librsvg rust | tail -1
> > total: 1052.9 MiB
> > --8<---------------cut here---------------end--------------->8---
> >
> > Perhaps the size issue can be somewhat mitigated by adding a “lib”
> > output to the Rust package, but even then it would probably still be an
> > issue.
> 
> Librsvg does not depend on Rust at run-time, so the closure size should
> be similar.  However I notice it has a 129MiB (!!) librsvg-2.a, which
> should be removed.  I will do that later.
> 
> > Also, is the new librsvg API-compatible with the old one?  IIUC it still
> > provides a C API, right?  Does guile-rsvg still work, for example?
> 
> I have not noticed any regressions since the switch.  The guile-rsvg
> tests pass, at least!
> 
> > What do other distros do?  Debian kept ‘librsvg-c’ around, primarily so
> > that architectures where Rust isn’t supported yet could still work:
> > <https://lwn.net/Articles/771355/>.
> 
> I wanted to ask about this: is Rust supported on all the platforms we
> support at the moment?

x86_64-unknown-linux, i686-unknown-linux, aarch64-unknow-linux,
 armv7-unknown-linux, did I miss anything?

https://forge.rust-lang.org/platform-support.html
 
> While depending on Rust for GTK/GNOME is unfortunate, I do think it's
> inevitable.
> 
> By the way, the next version of librsvg will require Rust 1.33 or
> thereabouts.