2024-04-22 09:13:57

by Miguel Ojeda

[permalink] [raw]
Subject: [PATCH] kbuild: rust: remove unneeded `@rustc_cfg` to avoid ICE

When KUnit tests are enabled, under very big kernel configurations
(e.g. `allyesconfig`), we can trigger a `rustdoc` ICE [1]:

RUSTDOC TK rust/kernel/lib.rs
error: the compiler unexpectedly panicked. this is a bug.

The reason is that this build step has a duplicated `@rustc_cfg` argument,
which contains the kernel configuration, and thus a lot of arguments. The
factor 2 happens to be enough to reach the ICE.

Thus remove the unneeded `@rustc_cfg`. By doing so, we clean up the
command and workaround the ICE.

The ICE has been fixed in the upcoming Rust 1.79 [2].

Cc: [email protected]
Fixes: a66d733da801 ("rust: support running Rust documentation tests as KUnit ones")
Link: https://github.com/rust-lang/rust/issues/122722 [1]
Link: https://github.com/rust-lang/rust/pull/122840 [2]
Signed-off-by: Miguel Ojeda <[email protected]>
---
rust/Makefile | 1 -
1 file changed, 1 deletion(-)

diff --git a/rust/Makefile b/rust/Makefile
index 846e6ab9d5a9..86a125c4243c 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -175,7 +175,6 @@ quiet_cmd_rustdoc_test_kernel = RUSTDOC TK $<
mkdir -p $(objtree)/$(obj)/test/doctests/kernel; \
OBJTREE=$(abspath $(objtree)) \
$(RUSTDOC) --test $(rust_flags) \
- @$(objtree)/include/generated/rustc_cfg \
-L$(objtree)/$(obj) --extern alloc --extern kernel \
--extern build_error --extern macros \
--extern bindings --extern uapi \

base-commit: 4cece764965020c22cff7665b18a012006359095
--
2.44.0



2024-04-22 09:26:11

by Alice Ryhl

[permalink] [raw]
Subject: Re: [PATCH] kbuild: rust: remove unneeded `@rustc_cfg` to avoid ICE

On Mon, Apr 22, 2024 at 11:13 AM Miguel Ojeda <[email protected]> wrote:
>
> When KUnit tests are enabled, under very big kernel configurations
> (e.g. `allyesconfig`), we can trigger a `rustdoc` ICE [1]:
>
> RUSTDOC TK rust/kernel/lib.rs
> error: the compiler unexpectedly panicked. this is a bug.
>
> The reason is that this build step has a duplicated `@rustc_cfg` argument,
> which contains the kernel configuration, and thus a lot of arguments. The
> factor 2 happens to be enough to reach the ICE.
>
> Thus remove the unneeded `@rustc_cfg`. By doing so, we clean up the
> command and workaround the ICE.
>
> The ICE has been fixed in the upcoming Rust 1.79 [2].
>
> Cc: [email protected]
> Fixes: a66d733da801 ("rust: support running Rust documentation tests as KUnit ones")
> Link: https://github.com/rust-lang/rust/issues/122722 [1]
> Link: https://github.com/rust-lang/rust/pull/122840 [2]
> Signed-off-by: Miguel Ojeda <[email protected]>

Reviewed-by: Alice Ryhl <[email protected]>

2024-04-23 01:04:18

by Miguel Ojeda

[permalink] [raw]
Subject: Re: [PATCH] kbuild: rust: remove unneeded `@rustc_cfg` to avoid ICE

On Mon, Apr 22, 2024 at 11:13 AM Miguel Ojeda <[email protected]> wrote:
>
> When KUnit tests are enabled, under very big kernel configurations
> (e.g. `allyesconfig`), we can trigger a `rustdoc` ICE [1]:
>
> RUSTDOC TK rust/kernel/lib.rs
> error: the compiler unexpectedly panicked. this is a bug.
>
> The reason is that this build step has a duplicated `@rustc_cfg` argument,
> which contains the kernel configuration, and thus a lot of arguments. The
> factor 2 happens to be enough to reach the ICE.
>
> Thus remove the unneeded `@rustc_cfg`. By doing so, we clean up the
> command and workaround the ICE.
>
> The ICE has been fixed in the upcoming Rust 1.79 [2].
>
> Cc: [email protected]
> Fixes: a66d733da801 ("rust: support running Rust documentation tests as KUnit ones")
> Link: https://github.com/rust-lang/rust/issues/122722 [1]
> Link: https://github.com/rust-lang/rust/pull/122840 [2]
> Signed-off-by: Miguel Ojeda <[email protected]>

Applied to `rust-fixes` early to start getting some testing in -next.
Please feel free to send tags for this one.

Cheers,
Miguel