[PATCH 09/33] rust: kbuild: make `--remap-path-prefix` workaround conditional

[Gary Guo]

On Wed Apr 1, 2026 at 12:45 PM BST, Miguel Ojeda wrote:
> The Internal Compiler Error that the comment mentions [1] was fixed in
> Rust 1.87.0 [2]. And, for other workarounds, we plan on limiting where
> we apply them [3].
>
> Thus limit the ICE one too.
>
> This will help to make sure the workaround is not needed anymore on
> newer versions.
>
> Link: https://github.com/rust-lang/rust/issues/138520 [1]
> Link: https://github.com/rust-lang/rust/pull/138556 [2]
> Link: https://lore.kernel.org/rust-for-linux/20260205131815.2943152-2-mlksvender@gmail.com/ [3]
> Signed-off-by: Miguel Ojeda <ojeda at kernel.org>
> ---
>  rust/Makefile | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/rust/Makefile b/rust/Makefile
> index 708530ee3613..163d2258e93f 100644
> --- a/rust/Makefile
> +++ b/rust/Makefile
> @@ -145,10 +145,12 @@ doctests_modifiers_workaround := $(rustdoc_modifiers_workaround)$(if $(call rust
>  # `rustdoc` ICEs on out-of-tree builds in Rust < 1.87.0
>  # (https://github.com/rust-lang/rust/issues/138520). Thus workaround the
>  # issue skipping the flag.
> +rustdoc_remap_workaround := $(if $(call rustc-min-version,108700),,--remap-path-prefix=%)

Okay, I see what the comments mean now. Perhaps squash this to the previous
commit?

Best,
Gary

> +
>  quiet_cmd_rustdoc = RUSTDOC $(if $(rustdoc_host),H, ) $<
>        cmd_rustdoc = \
>  	OBJTREE=$(abspath $(objtree)) \
> -	$(RUSTDOC) $(filter-out $(skip_flags) --remap-path-prefix=%,$(if $(rustdoc_host),$(rust_common_flags),$(rust_flags))) \
> +	$(RUSTDOC) $(filter-out $(skip_flags) $(rustdoc_remap_workaround),$(if $(rustdoc_host),$(rust_common_flags),$(rust_flags))) \
>  		$(rustc_target_flags) -L$(objtree)/$(obj) \
>  		-Zunstable-options --generate-link-to-definition \
>  		--output $(rustdoc_output) \