From 9418e686047421dcd416f694ea72fb9edeef3688 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 30 Jul 2023 00:03:17 +0200 Subject: rust: enable `no_mangle_with_rust_abi` Clippy lint Introduced in Rust 1.69.0 [1], this lint prevents forgetting to set the C ABI when using `#[no_mangle]` (or thinking it is implied). For instance, it would have prevented the issue [2] fixed by commit c682e4c37d2b ("rust: kernel: Mark rust_fmt_argument as extern "C""). error: `#[no_mangle]` set on a function with the default (`Rust`) ABI --> rust/kernel/print.rs:21:1 | 21 | / unsafe fn rust_fmt_argument( 22 | | buf: *mut c_char, 23 | | end: *mut c_char, 24 | | ptr: *const c_void, 25 | | ) -> *mut c_char { | |________________^ | = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#no_mangle_with_rust_abi = note: requested on the command line with `-D clippy::no-mangle-with-rust-abi` help: set an ABI | 21 | unsafe extern "C" fn rust_fmt_argument( | ++++++++++ help: or explicitly set the default | 21 | unsafe extern "Rust" fn rust_fmt_argument( | +++++++++++++ Thus enable it. In rare cases, we may need to use the Rust ABI even with `#[no_mangle]` (e.g. one case, before 1.71.0, would have been the `__rust_*` functions). In those cases, we would need to `#[allow(...)]` the lint, since using `extern "Rust"` explicitly (as the compiler suggests) currently gets overwritten by `rustfmt` [3]. Link: https://github.com/rust-lang/rust-clippy/issues/10347 [1] Link: https://github.com/Rust-for-Linux/linux/pull/967 [2] Link: https://github.com/rust-lang/rustfmt/issues/5701 [3] Reviewed-by: Trevor Gross Reviewed-by: Gary Guo Reviewed-by: Martin Rodriguez Reboredo Link: https://lore.kernel.org/r/20230729220317.416771-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/Makefile b/Makefile index a5880570a526..0c7f6240df2e 100644 --- a/Makefile +++ b/Makefile @@ -467,6 +467,7 @@ export rust_common_flags := --edition=2021 \ -Dclippy::let_unit_value -Dclippy::mut_mut \ -Dclippy::needless_bitwise_bool \ -Dclippy::needless_continue \ + -Dclippy::no_mangle_with_rust_abi \ -Wclippy::dbg_macro KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS) -- cgit v1.2.3