Re: [PATCH v2 2/2] scripts: generate_rust_analyzer.py: reduce cfg plumbing

[Tamir Duberstein]

On Tue, Jan 20, 2026 at 8:16 PM Jesung Yang <y.j3ms.n@xxxxxxxxx> wrote:
>
> On Wed Jan 21, 2026 at 1:10 AM KST, Tamir Duberstein wrote:
> > Centralize `cfg` lookup in `append_crate` to avoid having to do so for
> > each crate. Remove hardcoded `cfg`s for `pin-init{,-internal}` now that
> > these are passed from `rust/Makefile`.
> >
> > Signed-off-by: Tamir Duberstein <tamird@xxxxxxxxxx>
> > ---
> >  scripts/generate_rust_analyzer.py | 13 +++++--------
> >  1 file changed, 5 insertions(+), 8 deletions(-)
> >
> > diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_analyzer.py
> > index 147d0cc94068..b96d3cbe3df1 100755
> > --- a/scripts/generate_rust_analyzer.py
> > +++ b/scripts/generate_rust_analyzer.py
> > @@ -35,7 +35,9 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs, core_edit
> >      crates_indexes = {}
> >      crates_cfgs = args_crates_cfgs(cfgs)
> >
> > -    def append_crate(display_name, root_module, deps, cfg=[], is_workspace_member=True, is_proc_macro=False, edition="2021"):
> > +    def append_crate(display_name, root_module, deps, cfg=None, is_workspace_member=True, is_proc_macro=False, edition="2021"):
> > +        if cfg is None:
> > +            cfg = crates_cfgs.get(display_name, [])
>
> Could we add a brief comment explaining how the behavior of
> `append_crate` changes according to the `cfg` parameter? Since `None`
> and an empty list have different effects, documenting that distinction
> would make the intended behavior clearer.

I don't think this is necessary - it won't age well when we change the
entire API surface here in the next version of the series[0] that adds
type annotations.

Link: https://lore.kernel.org/all/20250424-rust-analyzer-host-v6-0-40e67fe5c38a@xxxxxxxxx/
[0]

> This would also help later when we add proper Python docstrings.

Same as above: a lot of change is coming. Is this worth considering right now?

>
> Thanks!
>
> Best regards,
> Jesung
>
> >          crate = {
> >              "display_name": display_name,
> >              "root_module": str(root_module),
> > @@ -60,7 +62,7 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs, core_edit
> >      def append_sysroot_crate(
> >          display_name,
> >          deps,
> > -        cfg=[],
> > +        cfg=None,
> >          edition="2021",
> >      ):
> >          append_crate(
> > @@ -75,7 +77,7 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs, core_edit
> >      # NB: sysroot crates reexport items from one another so setting up our transitive dependencies
> >      # here is important for ensuring that rust-analyzer can resolve symbols. The sources of truth
> >      # for this dependency graph are `(sysroot_src / crate / "Cargo.toml" for crate in crates)`.
> > -    append_sysroot_crate("core", [], cfg=crates_cfgs.get("core", []), edition=core_edition)
> > +    append_sysroot_crate("core", [], edition=core_edition)
> >      append_sysroot_crate("alloc", ["core"])
> >      append_sysroot_crate("std", ["alloc", "core"])
> >      append_sysroot_crate("proc_macro", ["core", "std"])
> > @@ -90,21 +92,18 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs, core_edit
> >          "proc_macro2",
> >          srctree / "rust" / "proc-macro2" / "lib.rs",
> >          ["core", "alloc", "std", "proc_macro"],
> > -        cfg=crates_cfgs["proc_macro2"],
> >      )
> >
> >      append_crate(
> >          "quote",
> >          srctree / "rust" / "quote" / "lib.rs",
> >          ["alloc", "proc_macro", "proc_macro2"],
> > -        cfg=crates_cfgs["quote"],
> >      )
> >
> >      append_crate(
> >          "syn",
> >          srctree / "rust" / "syn" / "lib.rs",
> >          ["proc_macro", "proc_macro2", "quote"],
> > -        cfg=crates_cfgs["syn"],
> >      )
> >
> >      append_crate(
> > @@ -124,7 +123,6 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs, core_edit
> >          "pin_init_internal",
> >          srctree / "rust" / "pin-init" / "internal" / "src" / "lib.rs",
> >          [],
> > -        cfg=["kernel"],
> >          is_proc_macro=True,
> >      )
> >
> > @@ -132,7 +130,6 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs, core_edit
> >          "pin_init",
> >          srctree / "rust" / "pin-init" / "src" / "lib.rs",
> >          ["core", "pin_init_internal", "macros"],
> > -        cfg=["kernel"],
> >      )
> >
> >      append_crate(
>