On Wed, Mar 12, 2025 at 5:30 PM Benno Lossin <benno.lossin@xxxxxxxxx> wrote: > > On Wed Mar 12, 2025 at 10:10 PM CET, Tamir Duberstein wrote: > > On Wed, Mar 12, 2025 at 5:04 PM Tamir Duberstein <tamird@xxxxxxxxx> wrote: > >> > >> On Wed, Mar 12, 2025 at 5:01 PM Benno Lossin <benno.lossin@xxxxxxxxx> wrote: > >> > Always enable the features, we have `allow(stable_features)` for this > >> > reason (then you don't have to do this dance with checking if it's > >> > already stable or not :) > >> > >> It's not so simple. In rustc < 1.84.0 the lints *and* the strict > >> provenance APIs are behind `feature(strict_provenance)`. In rustc >= > >> 1.84.0 the lints are behind `feature(strict_provenance_lints)`. So you > >> need to read the config to learn that you need to enable > >> `feature(strict_provenance_lints)`. > > I see... And `strict_provenance_lints` doesn't exist in <1.84? That's a > bit of a bummer... > > But I guess we could have this config option (in `init/Kconfig`): > > config RUSTC_HAS_STRICT_PROVENANCE > def_bool RUSTC_VERSION >= 108400 > > and then do this in `lib.rs`: > > #![cfg_attr(CONFIG_RUSTC_HAS_STRICT_PROVENANCE, feature(strict_provenance_lints))] Yep! That's exactly what I did, but as I mentioned up-thread, the result is that we only cover the `kernel` crate. > > > Actually this isn't even the only problem. It seems that > > `-Astable_features` doesn't affect features enabled on the command > > line at all: > > > > error[E0725]: the feature `strict_provenance` is not in the list of > > allowed features > > --> <crate attribute>:1:9 > > | > > 1 | feature(strict_provenance) > > | ^^^^^^^^^^^^^^^^^ > > That's because you need to append the feature to `rust_allowed_features` > in `scripts/Makefile.build` (AFAIK). Thanks, that's a helpful pointer, and it solves some problems but not all. The root Makefile contains this bit: > KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \ > -Zallow-features= $(HOSTRUSTFLAGS) which means we can't use the provenance lints against these host targets (including e.g. `rustdoc_test_gen`). We can't remove this -Zallow-features= either because then core fails to compile. I'm at the point where I think I need more involved help. Want to take a look at my attempt? It's here: https://github.com/tamird/linux/tree/b4/ptr-as-ptr. Thanks! Tamir
