6.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Miguel Ojeda ojeda@kernel.org
[ Upstream commit 52cae7f28ed6c3992489f16bb355f5b623f0912e ]
`scripts/rust_is_available.sh` calls `bindgen` with a special header in order to check whether the `libclang` version in use is suitable.
However, the invocation itself may fail if, for instance, `bindgen` cannot locate `libclang`. This is fine for Kconfig (since the script will still fail and therefore disable Rust as it should), but it is pretty confusing for users of the `rustavailable` target given the error will be unrelated:
./scripts/rust_is_available.sh: 21: arithmetic expression: expecting primary: "100000 * + 100 * + " make: *** [Makefile:1816: rustavailable] Error 2
Instead, run the `bindgen` invocation independently in a previous step, saving its output and return code. If it fails, then show the user a proper error message. Otherwise, continue as usual with the saved output.
Since the previous patch we show a reference to the docs, and the docs now explain how `bindgen` looks for `libclang`, thus the error message can leverage the documentation, avoiding duplication here (and making users aware of the setup guide in the documentation).
Reported-by: Nick Desaulniers ndesaulniers@google.com Link: https://lore.kernel.org/rust-for-linux/CAKwvOdm5JT4wbdQQYuW+RT07rCi6whGBM2iU... Reported-by: François Valenduc francoisvalenduc@gmail.com Closes: https://github.com/Rust-for-Linux/linux/issues/934 Reported-by: Alexandru Radovici msg4alex@gmail.com Closes: https://github.com/Rust-for-Linux/linux/pull/921 Reported-by: Matthew Leach dev@mattleach.net Closes: https://lore.kernel.org/rust-for-linux/20230507084116.1099067-1-dev@mattleac... Fixes: 78521f3399ab ("scripts: add `rust_is_available.sh`") Reviewed-by: Martin Rodriguez Reboredo yakoyoku@gmail.com Reviewed-by: Masahiro Yamada masahiroy@kernel.org Reviewed-by: Nathan Chancellor nathan@kernel.org Link: https://lore.kernel.org/r/20230616001631.463536-6-ojeda@kernel.org Signed-off-by: Miguel Ojeda ojeda@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- scripts/rust_is_available.sh | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh index 0c9be438e4cd3..c965895d80b97 100755 --- a/scripts/rust_is_available.sh +++ b/scripts/rust_is_available.sh @@ -90,8 +90,28 @@ if [ "$rust_bindings_generator_cversion" -gt "$rust_bindings_generator_min_cvers fi
# Check that the `libclang` used by the Rust bindings generator is suitable. +# +# In order to do that, first invoke `bindgen` to get the `libclang` version +# found by `bindgen`. This step may already fail if, for instance, `libclang` +# is not found, thus inform the user in such a case. +bindgen_libclang_output=$( \ + LC_ALL=C "$BINDGEN" $(dirname $0)/rust_is_available_bindgen_libclang.h 2>&1 >/dev/null +) || bindgen_libclang_code=$? +if [ -n "$bindgen_libclang_code" ]; then + echo >&2 "***" + echo >&2 "*** Running '$BINDGEN' to check the libclang version (used by the Rust" + echo >&2 "*** bindings generator) failed with code $bindgen_libclang_code. This may be caused by" + echo >&2 "*** a failure to locate libclang. See output and docs below for details:" + echo >&2 "***" + echo >&2 "$bindgen_libclang_output" + echo >&2 "***" + exit 1 +fi + +# `bindgen` returned successfully, thus use the output to check that the version +# of the `libclang` found by the Rust bindings generator is suitable. bindgen_libclang_version=$( \ - LC_ALL=C "$BINDGEN" $(dirname $0)/rust_is_available_bindgen_libclang.h 2>&1 >/dev/null \ + echo "$bindgen_libclang_output" \ | grep -F 'clang version ' \ | grep -oE '[0-9]+.[0-9]+.[0-9]+' \ | head -n 1 \