On Wed, Mar 12, 2025 at 6:38 PM Benno Lossin <benno.lossin@xxxxxxxxx> wrote: > > On Wed Mar 12, 2025 at 11:24 PM CET, Tamir Duberstein wrote: > > 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. > > Ah I see, can't we just have the above line in the other crate roots? The most difficult case is doctests. You'd have to add this to every example AFAICT. > >> > 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. > > I'll take a look tomorrow, you're testing my knowledge of the build > system a lot here :) We're guaranteed to learn something :)
