[INFO] fetching crate xxcalc 0.2.1...
[INFO] checking xxcalc-0.2.1 against 1.95.0 for pr-155915
[INFO] extracting crate xxcalc 0.2.1 into /workspace/builds/worker-4-tc1/source
[INFO] started tweaking crates.io crate xxcalc 0.2.1
[INFO] finished tweaking crates.io crate xxcalc 0.2.1
[INFO] tweaked toml for crates.io crate xxcalc 0.2.1 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate xxcalc 0.2.1 on toolchain 1.95.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 10 packages to latest compatible versions
[INFO] [stderr]       Adding rustyline v1.0.0 (available: v18.0.0)
[INFO] [stderr]       Adding smallvec v0.2.1 (available: v1.15.1)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rustyline v1.0.0
[INFO] [stderr]   Downloaded encode_unicode v0.1.3
[INFO] [stderr]   Downloaded nix v0.5.1
[INFO] [stderr]   Downloaded smallvec v0.2.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d0f7baab01b7d0a06244680e262eb15995d9d82c0b954bfd137241b5d7731c9d
[INFO] running `Command { std: "docker" "start" "-a" "d0f7baab01b7d0a06244680e262eb15995d9d82c0b954bfd137241b5d7731c9d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d0f7baab01b7d0a06244680e262eb15995d9d82c0b954bfd137241b5d7731c9d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d0f7baab01b7d0a06244680e262eb15995d9d82c0b954bfd137241b5d7731c9d", kill_on_drop: false }`
[INFO] [stdout] d0f7baab01b7d0a06244680e262eb15995d9d82c0b954bfd137241b5d7731c9d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 966d5543608681c79fd2d38418e6a1852a53d7417dee65303f55a99fbabd0ed7
[INFO] running `Command { std: "docker" "start" "-a" "966d5543608681c79fd2d38418e6a1852a53d7417dee65303f55a99fbabd0ed7", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] [stderr]     Checking smallvec v0.2.1
[INFO] [stderr]     Checking xxcalc v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused macro definition: `tokenize`
[INFO] [stdout]    --> src/tokenizer.rs:267:14
[INFO] [stdout]     |
[INFO] [stdout] 267 | macro_rules! tokenize {
[INFO] [stdout]     |              ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_macros)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused macro definition: `tokenize_ref`
[INFO] [stdout]    --> src/tokenizer.rs:271:14
[INFO] [stdout]     |
[INFO] [stdout] 271 | macro_rules! tokenize_ref {
[INFO] [stdout]     |              ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/evaluator.rs:250:24
[INFO] [stdout]     |
[INFO] [stdout] 250 |           let result = try!(self.call_function(&x.to_string(), position, &mut stack));
[INFO] [stdout]     |                        ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/evaluator.rs:261:24
[INFO] [stdout]     |
[INFO] [stdout] 261 |           let result = try!(self.call_function(&x, position, &mut stack));
[INFO] [stdout]     |                        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]   --> src/calculator.rs:52:25
[INFO] [stdout]    |
[INFO] [stdout] 52 |     let parsed_tokens = try!(parser.process(tokens));
[INFO] [stdout]    |                         ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]   --> src/calculator.rs:53:21
[INFO] [stdout]    |
[INFO] [stdout] 53 |     let evaluated = try!(evaluator.process(parsed_tokens));
[INFO] [stdout]    |                     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/polynomial_calculator.rs:261:29
[INFO] [stdout]     |
[INFO] [stdout] 261 |     Ok(Polynomial::constant(try!(args[0].as_f64()).log(try!(args[1].as_f64()))))
[INFO] [stdout]     |                             ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/polynomial_calculator.rs:261:56
[INFO] [stdout]     |
[INFO] [stdout] 261 |     Ok(Polynomial::constant(try!(args[0].as_f64()).log(try!(args[1].as_f64()))))
[INFO] [stdout]     |                                                        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/polynomial_calculator.rs:280:29
[INFO] [stdout]     |
[INFO] [stdout] 280 |     Ok(Polynomial::constant(try!(args[0].as_f64()).log10()))
[INFO] [stdout]     |                             ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/polynomial_calculator.rs:302:21
[INFO] [stdout]     |
[INFO] [stdout] 302 |     Ok(args[0].bind(try!(args[1].as_f64())))
[INFO] [stdout]     |                     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/evaluator.rs:15:31
[INFO] [stdout]    |
[INFO] [stdout] 15 | pub type FunctionHandle = Box<Fn(Vec<Polynomial>) -> Result<Polynomial, EvaluationError>>;
[INFO] [stdout]    |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 15 | pub type FunctionHandle = Box<dyn Fn(Vec<Polynomial>) -> Result<Polynomial, EvaluationError>>;
[INFO] [stdout]    |                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]    --> src/polynomial.rs:416:5
[INFO] [stdout]     |
[INFO] [stdout] 416 |     self + &other;
[INFO] [stdout]     |     ^^^^^^^^^^^^^ the arithmetic operation produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 416 |     let _ = self + &other;
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]    --> src/polynomial.rs:500:5
[INFO] [stdout]     |
[INFO] [stdout] 500 |     self - &other;
[INFO] [stdout]     |     ^^^^^^^^^^^^^ the arithmetic operation produces a value
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 500 |     let _ = self - &other;
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]    --> src/polynomial.rs:596:5
[INFO] [stdout]     |
[INFO] [stdout] 596 |     self * &other;
[INFO] [stdout]     |     ^^^^^^^^^^^^^ the arithmetic operation produces a value
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 596 |     let _ = self * &other;
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `mul` that must be used
[INFO] [stdout]    --> src/polynomial.rs:618:5
[INFO] [stdout]     |
[INFO] [stdout] 618 |     self.mul(other);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this returns the result of the operation, without modifying the original
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 618 |     let _ = self.mul(other);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused macro definition: `tokenize`
[INFO] [stdout]    --> src/tokenizer.rs:267:14
[INFO] [stdout]     |
[INFO] [stdout] 267 | macro_rules! tokenize {
[INFO] [stdout]     |              ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_macros)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/evaluator.rs:250:24
[INFO] [stdout]     |
[INFO] [stdout] 250 |           let result = try!(self.call_function(&x.to_string(), position, &mut stack));
[INFO] [stdout]     |                        ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/evaluator.rs:261:24
[INFO] [stdout]     |
[INFO] [stdout] 261 |           let result = try!(self.call_function(&x, position, &mut stack));
[INFO] [stdout]     |                        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/evaluator.rs:559:31
[INFO] [stdout]     |
[INFO] [stdout] 559 |       Ok(Polynomial::constant(try!(args[0].clone().as_f64()) % try!(args[1].clone().as_f64())))
[INFO] [stdout]     |                               ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/evaluator.rs:559:64
[INFO] [stdout]     |
[INFO] [stdout] 559 |       Ok(Polynomial::constant(try!(args[0].clone().as_f64()) % try!(args[1].clone().as_f64())))
[INFO] [stdout]     |                                                                ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]   --> src/calculator.rs:52:25
[INFO] [stdout]    |
[INFO] [stdout] 52 |     let parsed_tokens = try!(parser.process(tokens));
[INFO] [stdout]    |                         ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]   --> src/calculator.rs:53:21
[INFO] [stdout]    |
[INFO] [stdout] 53 |     let evaluated = try!(evaluator.process(parsed_tokens));
[INFO] [stdout]    |                     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/polynomial_calculator.rs:261:29
[INFO] [stdout]     |
[INFO] [stdout] 261 |     Ok(Polynomial::constant(try!(args[0].as_f64()).log(try!(args[1].as_f64()))))
[INFO] [stdout]     |                             ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/polynomial_calculator.rs:261:56
[INFO] [stdout]     |
[INFO] [stdout] 261 |     Ok(Polynomial::constant(try!(args[0].as_f64()).log(try!(args[1].as_f64()))))
[INFO] [stdout]     |                                                        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/polynomial_calculator.rs:280:29
[INFO] [stdout]     |
[INFO] [stdout] 280 |     Ok(Polynomial::constant(try!(args[0].as_f64()).log10()))
[INFO] [stdout]     |                             ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/polynomial_calculator.rs:302:21
[INFO] [stdout]     |
[INFO] [stdout] 302 |     Ok(args[0].bind(try!(args[1].as_f64())))
[INFO] [stdout]     |                     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> benches/parser.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/evaluator.rs:15:31
[INFO] [stdout]    |
[INFO] [stdout] 15 | pub type FunctionHandle = Box<Fn(Vec<Polynomial>) -> Result<Polynomial, EvaluationError>>;
[INFO] [stdout]    |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 15 | pub type FunctionHandle = Box<dyn Fn(Vec<Polynomial>) -> Result<Polynomial, EvaluationError>>;
[INFO] [stdout]    |                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `xxcalc` (bench "parser") due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> benches/polynomial_calculator.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> benches/evaluator.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> benches/tokenizer.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `xxcalc` (bench "tokenizer") due to 1 previous error
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `xxcalc` (bench "evaluator") due to 1 previous error
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `xxcalc` (bench "polynomial_calculator") due to 1 previous error
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]    --> src/polynomial.rs:416:5
[INFO] [stdout]     |
[INFO] [stdout] 416 |     self + &other;
[INFO] [stdout]     |     ^^^^^^^^^^^^^ the arithmetic operation produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 416 |     let _ = self + &other;
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]    --> src/polynomial.rs:500:5
[INFO] [stdout]     |
[INFO] [stdout] 500 |     self - &other;
[INFO] [stdout]     |     ^^^^^^^^^^^^^ the arithmetic operation produces a value
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 500 |     let _ = self - &other;
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]    --> src/polynomial.rs:596:5
[INFO] [stdout]     |
[INFO] [stdout] 596 |     self * &other;
[INFO] [stdout]     |     ^^^^^^^^^^^^^ the arithmetic operation produces a value
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 596 |     let _ = self * &other;
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `mul` that must be used
[INFO] [stdout]    --> src/polynomial.rs:618:5
[INFO] [stdout]     |
[INFO] [stdout] 618 |     self.mul(other);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this returns the result of the operation, without modifying the original
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 618 |     let _ = self.mul(other);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "966d5543608681c79fd2d38418e6a1852a53d7417dee65303f55a99fbabd0ed7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "966d5543608681c79fd2d38418e6a1852a53d7417dee65303f55a99fbabd0ed7", kill_on_drop: false }`
[INFO] [stdout] 966d5543608681c79fd2d38418e6a1852a53d7417dee65303f55a99fbabd0ed7
