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The let >> binding in `stack_pin_init` will thus become unreachable and produce a >> "unreachable expression" warning for subsequent match, and thus will fai= l >> `-Dwarnings` build. For this macro, all we need to know is that the erro= r >> type is uninhabited, so replace this with a irrefutable pattern instead. >> >> Reported-by: Mohamad Alsadhan >> Closes: https://github.com/Rust-for-Linux/pin-init/pull/171 >> Signed-off-by: Gary Guo > > Applied to `rust-fixes` -- thanks! > > For stable, we will need a custom backport without > `feature(min_exhaustive_patterns)` (we could in principle enable that > one since it is available in Rust 1.77.0, but for stable I would avoid > it), so I wrote this tag: We can probably just allow `unreachable_code`? Best, Gary > > Cc: stable@vger.kernel.org # Needed in 7.1.y and later (for 6.12.y > and 6.18.y a custom one is needed). > > [ The error looks like (dummy reproducer): > > error: unreachable expression > --> rust/kernel/sync.rs:177:5 > | > 177 | pin_init::stack_pin_init!(let num =3D 42u32); > | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > | | > | unreachable expression > | any code following this expression is unreachable > | > =3D note: `-D unreachable-code` implied by `-D warnings` > =3D help: to override `-D warnings` add `#[allow(unreachabl= e_code)]` > =3D note: this error originates in the macro > `pin_init::stack_pin_init` (in Nightly builds, run with -Z > macro-backtrace for more info) > > - Miguel ] > > [ Reworded for typos. - Miguel ] > > Cheers, > Miguel