Re: [PATCH v2 10/11] kbuild: rust_is_available: check that output looks as expected

[Nathan Chancellor <nathan@kernel.org>]

On Fri, Jun 16, 2023 at 02:16:30AM +0200, Miguel Ojeda wrote:
> The script already checks for `$RUSTC` and `$BINDGEN` existing
> and exiting without failure. However, one may still pass an
> unexpected binary that does not output what the later parsing
> expects. The script still successfully reports a failure as
> expected, but the error is confusing. For instance:
> 
>     $ RUSTC=true BINDGEN=bindgen CC=clang scripts/rust_is_available.sh
>     scripts/rust_is_available.sh: 19: arithmetic expression: expecting primary: "100000 *  + 100 *  + "
>     ***
>     *** Please see Documentation/rust/quick-start.rst for details
>     *** on how to set up the Rust support.
>     ***
> 
> Thus add an explicit check and a proper message for unexpected
> output from the called command.
> 
> Similarly, do so for the `libclang` version parsing, too.
> 
> Link: https://lore.kernel.org/rust-for-linux/CAK7LNAQYk6s11MASRHW6oxtkqF00EJVqhHOP=5rynWt-QDUsXw@mail.gmail.com/
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Nathan Chancellor <nathan@kernel.org>

> ---
>  scripts/rust_is_available.sh | 28 ++++++++++++++++++++++++++++
>  1 file changed, 28 insertions(+)
> 
> diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh
> index da8296cd9b8d..117018946b57 100755
> --- a/scripts/rust_is_available.sh
> +++ b/scripts/rust_is_available.sh
> @@ -97,6 +97,15 @@ rust_compiler_version=$( \
>  	echo "$rust_compiler_output" \
>  		| sed -nE '1s:.*rustc ([0-9]+\.[0-9]+\.[0-9]+).*:\1:p'
>  )
> +if [ -z "$rust_compiler_version" ]; then
> +	echo >&2 "***"
> +	echo >&2 "*** Running '$RUSTC' to check the Rust compiler version did not return"
> +	echo >&2 "*** an expected output. See output and docs below for details:"
> +	echo >&2 "***"
> +	echo >&2 "$rust_compiler_output"
> +	echo >&2 "***"
> +	exit 1
> +fi
>  rust_compiler_min_version=$($min_tool_version rustc)
>  rust_compiler_cversion=$(get_canonical_version $rust_compiler_version)
>  rust_compiler_min_cversion=$(get_canonical_version $rust_compiler_min_version)
> @@ -136,6 +145,15 @@ rust_bindings_generator_version=$( \
>  	echo "$rust_bindings_generator_output" \
>  		| sed -nE '1s:.*bindgen ([0-9]+\.[0-9]+\.[0-9]+).*:\1:p'
>  )
> +if [ -z "$rust_bindings_generator_version" ]; then
> +	echo >&2 "***"
> +	echo >&2 "*** Running '$BINDGEN' to check the bindings generator version did not return"
> +	echo >&2 "*** an expected output. See output and docs below for details:"
> +	echo >&2 "***"
> +	echo >&2 "$rust_bindings_generator_output"
> +	echo >&2 "***"
> +	exit 1
> +fi
>  rust_bindings_generator_min_version=$($min_tool_version bindgen)
>  rust_bindings_generator_cversion=$(get_canonical_version $rust_bindings_generator_version)
>  rust_bindings_generator_min_cversion=$(get_canonical_version $rust_bindings_generator_min_version)
> @@ -184,6 +202,16 @@ bindgen_libclang_version=$( \
>  	echo "$bindgen_libclang_output" \
>  		| sed -nE 's:.*clang version ([0-9]+\.[0-9]+\.[0-9]+).*:\1:p'
>  )
> +if [ -z "$bindgen_libclang_version" ]; then
> +	echo >&2 "***"
> +	echo >&2 "*** Running '$BINDGEN' to check the libclang version (used by the Rust"
> +	echo >&2 "*** bindings generator) did not return an expected output. See output"
> +	echo >&2 "*** and docs below for details:"
> +	echo >&2 "***"
> +	echo >&2 "$bindgen_libclang_output"
> +	echo >&2 "***"
> +	exit 1
> +fi
>  bindgen_libclang_min_version=$($min_tool_version llvm)
>  bindgen_libclang_cversion=$(get_canonical_version $bindgen_libclang_version)
>  bindgen_libclang_min_cversion=$(get_canonical_version $bindgen_libclang_min_version)
> -- 
> 2.41.0
>