Re: [PATCH v5 7/9] BreakingChanges: announce Rust becoming mandatory

> On 15/09/2025 12:22, Patrick Steinhardt wrote:
> > Over the last couple of years the appetite for bringing Rust into the
> > codebase has grown significantly across the developer base. Introducing
> > Rust is a major change though and has ramifications for the whole
> > ecosystem:
> > 
> >    - Some platforms have a Rust toolchain available, but have not yet
> >      integrated it into their build infrastructure.
> > 
> >    - Some platforms don't have any support for Rust at all.
> > 
> >    - Some platforms may have to figure out how to fit Rust into their
> >      bootstrapping sequence.
> > 
> > Due to this, and given that Git is a critical piece of infrastructure
> > for the whole industry, we cannot just introduce such a heavyweight
> > dependency without doing our due diligence.
> 
> I'm not sure what you mean by "doing our due diligence" here. We already
> know that requiring a rust compiler will make it impossible to build git on
> some currently supported platforms. Isn't the purpose of this patch to give
> them notice so they have some time to come up with a plan for either (a)
> accelerating rust support on their platform, or (b) for how maintain the LTS
> branch after the we stop supporting it?

> > +1. Initially, with Git 2.52, support for Rust will be auto-detected by Meson and
> > +   disabled in our Makefile so that the project can sort out the initial
> > +   infrastructure.
> > +2. In Git 2.53, both build systems will default-enable support for Rust.
> > +   Consequently, builds will break by default if Rust is not available on the
> > +   build host. The use of Rust can still be explicitly disabled via build
> > +   flags.
> > +3. In Git 3.0, the build options will be removed and support for Rust is
> > +   mandatory.
> > +--
> > ++
> > +You can explicitly ask both Meson and our Makefile-based system to enable Rust
> > +by saying `meson configure -Drust=enabled` and `make WITH_RUST=YesPlease`,
> > +respectively.
> 
> This is helpful but ideally before Git 2.53 we'd make the Makefile and meson
> print that information if they fail due to a missing rust compiler.

> > +The Git project will declare the last version before Git 3.0 to be a long-term
> > +support release. This long-term release will receive important bug fixes for at
> > +least four release cycles and security fixes for six release cycles. The Git
> > +project will hand over maintainership of the long-term release to distributors
> > +in case they need to extend the life of that long-term release even further. In
> > +that case, the backporting process will be handled by these distributors, but
> > +the backported patches will be reviewed on the mailing list and pulled in by the
> > +Git maintainer.
> 
> Didn't Junio have some qualms about the last part of this paragraph? I
> thought he suggested that once we hand over maintaining the LTS release the
> people responsible for it could use the security list to coordinate their
> work and would be responsible for pushing fixes the the LTS branch
> themselves.
> 
> Thanks for working on this, it will be good to have a formal plan in our
> Documentation that we can refer to.