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]
Signed-off-by: Miguel Ojeda <[email protected]>
---
Makefile | 1 +
1 file changed, 1 insertion(+)
diff --git a/Makefile b/Makefile
index 658ec2b8aa74..93bf3eca3ead 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)
--
2.41.0
On 7/29/23 19:03, Miguel Ojeda wrote:
> 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]
> Signed-off-by: Miguel Ojeda <[email protected]>
> ---
> [...]
Reviewed-by: Martin Rodriguez Reboredo <[email protected]>
On Sat, Jul 29, 2023 at 6:05 PM Miguel Ojeda <[email protected]> wrote:
>
> 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]
> Signed-off-by: Miguel Ojeda <[email protected]>
> ---
> [...]
Reviewed-by: Trevor Gross <[email protected]>
On Sun, 30 Jul 2023 00:03:17 +0200
Miguel Ojeda <[email protected]> wrote:
> 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]
> Signed-off-by: Miguel Ojeda <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
> ---
> Makefile | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/Makefile b/Makefile
> index 658ec2b8aa74..93bf3eca3ead 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)