[PATCH v2 09/11] kbuild: rust_is_available: handle failures calling `$RUSTC`/`$BINDGEN`

Miguel Ojeda
2023-06-16T00:18:51Z

The script already checks if `$RUSTC` and `$BINDGEN` exists via
`command`, but the environment variables may point to a
non-executable file, or the programs may fail for some other reason.
While the script successfully exits with a failure as it should,
the error given can be quite confusing depending on the shell and
the behavior of its `command`. For instance, with `dash`:

$ RUSTC=./mm BINDGEN=bindgen CC=clang scripts/rust_is_available.sh
scripts/rust_is_available.sh: 19: arithmetic expression: expecting primary: "100000 * + 100 * + "

Thus detect failure exit codes when calling `$RUSTC` and `$BINDGEN` and
print a better message, in a similar way to what we do when extracting
the `libclang` version found by `bindgen`.

Link: https://lore.kernel.org/rust-for-linux/CAK7LNAQYk6s11MASRHW6oxtkqF00EJVqhHOP=5rynWt-QDUsXw@mail.gmail.com/
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
scripts/rust_is_available.sh | 28 ++++++++++++++++++++++++++--
1 file changed, 26 insertions(+), 2 deletions(-)

diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh
index b7e0781fdea9..da8296cd9b8d 100755
--- a/scripts/rust_is_available.sh
+++ b/scripts/rust_is_available.sh
@@ -81,8 +81,20 @@ fi
# Check that the Rust compiler version is suitable.
#
# Non-stable and distributions' versions may have a version suffix, e.g. `-dev`.
+rust_compiler_output=$( \
+ LC_ALL=C "$RUSTC" --version 2>/dev/null
+) || rust_compiler_code=$?
+if [ -n "$rust_compiler_code" ]; then
+ echo >&2 "***"
+ echo >&2 "*** Running '$RUSTC' to check the Rust compiler version failed with"
+ echo >&2 "*** code $rust_compiler_code. See output and docs below for details:"
+ echo >&2 "***"
+ echo >&2 "$rust_compiler_output"
+ echo >&2 "***"
+ exit 1
+fi
rust_compiler_version=$( \
- LC_ALL=C "$RUSTC" --version 2>/dev/null \
+ echo "$rust_compiler_output" \
| sed -nE '1s:.*rustc ([0-9]+\.[0-9]+\.[0-9]+).*:\1:p'
)
rust_compiler_min_version=$($min_tool_version rustc)
@@ -108,8 +120,20 @@ fi
# Check that the Rust bindings generator is suitable.
#
# Non-stable and distributions' versions may have a version suffix, e.g. `-dev`.
+rust_bindings_generator_output=$( \
+ LC_ALL=C "$BINDGEN" --version 2>/dev/null
+) || rust_bindings_generator_code=$?
+if [ -n "$rust_bindings_generator_code" ]; then
+ echo >&2 "***"
+ echo >&2 "*** Running '$BINDGEN' to check the Rust bindings generator version failed with"
+ echo >&2 "*** code $rust_bindings_generator_code. See output and docs below for details:"
+ echo >&2 "***"
+ echo >&2 "$rust_bindings_generator_output"
+ echo >&2 "***"
+ exit 1
+fi
rust_bindings_generator_version=$( \
- LC_ALL=C "$BINDGEN" --version 2>/dev/null \
+ echo "$rust_bindings_generator_output" \
| sed -nE '1s:.*bindgen ([0-9]+\.[0-9]+\.[0-9]+).*:\1:p'
)
rust_bindings_generator_min_version=$($min_tool_version bindgen)
--
2.41.0