[INFO] cloning repository https://github.com/syuni/rust-by-example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/syuni/rust-by-example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsyuni%2Frust-by-example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsyuni%2Frust-by-example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b3f4cf9a5219e47165d823446a761a963ce48beb
[INFO] testing syuni/rust-by-example against master#62efba8a050c64249dab942951bb28f710208bc8 for pr-90799
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsyuni%2Frust-by-example" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/syuni/rust-by-example on toolchain 62efba8a050c64249dab942951bb28f710208bc8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/syuni/rust-by-example
[INFO] finished tweaking git repo https://github.com/syuni/rust-by-example
[INFO] tweaked toml for git repo https://github.com/syuni/rust-by-example written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/syuni/rust-by-example already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: file found to be present in multiple build targets: /workspace/builds/worker-2/source/src/8_2_4.rs
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:e8397a04204aaf8b9f284182a6f9e27a3c2e67044d0943b4415b160bfc957681" "/opt/rustwide/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ff55e6705017e7bd98ed4f0c5822bc067282c131285747d0e0eb55ddd64f5542
[INFO] running `Command { std: "docker" "start" "-a" "ff55e6705017e7bd98ed4f0c5822bc067282c131285747d0e0eb55ddd64f5542", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ff55e6705017e7bd98ed4f0c5822bc067282c131285747d0e0eb55ddd64f5542", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ff55e6705017e7bd98ed4f0c5822bc067282c131285747d0e0eb55ddd64f5542", kill_on_drop: false }`
[INFO] [stdout] ff55e6705017e7bd98ed4f0c5822bc067282c131285747d0e0eb55ddd64f5542
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "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:e8397a04204aaf8b9f284182a6f9e27a3c2e67044d0943b4415b160bfc957681" "/opt/rustwide/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] af31d15578374b63c449eb1999c40412c787b2ac11dd84834fbcb7b96e5d8d9e
[INFO] running `Command { std: "docker" "start" "-a" "af31d15578374b63c449eb1999c40412c787b2ac11dd84834fbcb7b96e5d8d9e", kill_on_drop: false }`
[INFO] [stderr] warning: file found to be present in multiple build targets: /opt/rustwide/workdir/src/8_2_4.rs
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rust-by-example v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/18_4_1.rs:14:68
[INFO] [stdout]    |
[INFO] [stdout] 14 |         Err(why) => panic!("couldn't open {}: {}", display, Error::description(&why)),
[INFO] [stdout]    |                                                                    ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/18_4_1.rs:21:68
[INFO] [stdout]    |
[INFO] [stdout] 21 |         Err(why) => panic!("couldn't read {}: {}", display, Error::description(&why)),
[INFO] [stdout]    |                                                                    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021
[INFO] [stdout]   --> src/8_2_6_1.rs:16:40
[INFO] [stdout]    |
[INFO] [stdout] 16 |     println!("2 in array2: {}", array2.into_iter().any(|&x| x == 2));
[INFO] [stdout]    |                                        ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]    = warning: this changes meaning in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]    |
[INFO] [stdout] 16 |     println!("2 in array2: {}", array2.iter().any(|&x| x == 2));
[INFO] [stdout]    |                                        ~~~~
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]    |
[INFO] [stdout] 16 |     println!("2 in array2: {}", IntoIterator::into_iter(array2).any(|&x| x == 2));
[INFO] [stdout]    |                                 ++++++++++++++++++++++++      ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: expected one of `:`, `@`, or `|`, found `,`
[INFO] [stdout]  --> src/13_7_1.rs:6:26
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn contains(&self, &A, &B) -> bool; // `A`と`B`の両方を明示的に要求する
[INFO] [stdout]   |                          ^ expected one of `:`, `@`, or `|`
[INFO] [stdout]   |
[INFO] [stdout]   = note: anonymous parameters are removed in the 2018 edition (see RFC 1685)
[INFO] [stdout] help: if this is a parameter name, give it a type
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn contains(&self, A: &TypeName, &B) -> bool; // `A`と`B`の両方を明示的に要求する
[INFO] [stdout]   |                        ~~~~~~~~~~~~
[INFO] [stdout] help: if this is a type, explicitly ignore the parameter name
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn contains(&self, _: &A, &B) -> bool; // `A`と`B`の両方を明示的に要求する
[INFO] [stdout]   |                        ++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust-by-example` due to 2 previous errors
[INFO] [stdout] error: expected type, found `}`
[INFO] [stdout]   --> src/14_4_6.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 20 |         println!("{} is the first", choose_first(&first, &second)):
[INFO] [stdout]    |                                                                   - help: try using a semicolon: `;`
[INFO] [stdout] 21 |     };
[INFO] [stdout]    |     ^ expected type
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#![feature(type_ascription)]` lets you annotate an expression with a type: `<expr>: <type>`
[INFO] [stdout]    = note: see issue #23416 <https://github.com/rust-lang/rust/issues/23416> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: expected one of `:`, `@`, or `|`, found `)`
[INFO] [stdout]  --> src/13_7_1.rs:6:30
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn contains(&self, &A, &B) -> bool; // `A`と`B`の両方を明示的に要求する
[INFO] [stdout]   |                              ^ expected one of `:`, `@`, or `|`
[INFO] [stdout]   |
[INFO] [stdout]   = note: anonymous parameters are removed in the 2018 edition (see RFC 1685)
[INFO] [stdout] help: if this is a parameter name, give it a type
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn contains(&self, &A, B: &TypeName) -> bool; // `A`と`B`の両方を明示的に要求する
[INFO] [stdout]   |                            ~~~~~~~~~~~~
[INFO] [stdout] help: if this is a type, explicitly ignore the parameter name
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn contains(&self, &A, _: &B) -> bool; // `A`と`B`の両方を明示的に要求する
[INFO] [stdout]   |                            ++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: expected one of `!`, `(`, `...`, `..=`, `..`, `::`, `:`, `{`, or `|`, found `,`
[INFO] [stdout]   --> src/13_7_2.rs:10:32
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn contains(&self, &Self::A, &Self::B) -> bool;
[INFO] [stdout]    |                                ^ expected one of 9 possible tokens
[INFO] [stdout]    |
[INFO] [stdout]    = note: anonymous parameters are removed in the 2018 edition (see RFC 1685)
[INFO] [stdout] help: explicitly ignore the parameter name
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn contains(&self, _: &Self::A, &Self::B) -> bool;
[INFO] [stdout]    |                        ~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: expected one of `!`, `(`, `...`, `..=`, `..`, `::`, `:`, `{`, or `|`, found `)`
[INFO] [stdout]   --> src/13_7_2.rs:10:42
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn contains(&self, &Self::A, &Self::B) -> bool;
[INFO] [stdout]    |                                          ^ expected one of 9 possible tokens
[INFO] [stdout]    |
[INFO] [stdout]    = note: anonymous parameters are removed in the 2018 edition (see RFC 1685)
[INFO] [stdout] help: explicitly ignore the parameter name
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn contains(&self, &Self::A, _: &Self::B) -> bool;
[INFO] [stdout]    |                                  ~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot pass `self` by raw pointer
[INFO] [stdout]   --> src/16_10.rs:39:15
[INFO] [stdout]    |
[INFO] [stdout] 39 |     fn cause(*self) -> Option<&error::Error> {
[INFO] [stdout]    |               ^^^^ cannot pass `self` by raw pointer
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `x`
[INFO] [stdout]  --> src/17_1.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     x: f64,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]  --> src/17_1.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     y: f64,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused label
[INFO] [stdout]  --> src/7_2_1.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |         'inner: loop {
[INFO] [stdout]   |         ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_labels)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `noisy_unused_function`
[INFO] [stdout]  --> src/12_1.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn noisy_unused_function() {}
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021
[INFO] [stdout]   --> src/8_2_6_2.rs:23:16
[INFO] [stdout]    |
[INFO] [stdout] 23 |         array2.into_iter().find(|&&x| x == 2)
[INFO] [stdout]    |                ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]    = warning: this changes meaning in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]    |
[INFO] [stdout] 23 |         array2.iter().find(|&&x| x == 2)
[INFO] [stdout]    |                ~~~~
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]    |
[INFO] [stdout] 23 |         IntoIterator::into_iter(array2).find(|&&x| x == 2)
[INFO] [stdout]    |         ++++++++++++++++++++++++      ~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]   --> src/6.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |         2 * x;
[INFO] [stdout]    |         ^^^^^ the arithmetic operation produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 14 |         let _ = 2 * x;
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `function`
[INFO] [stdout]  --> src/10_4.rs:6:12
[INFO] [stdout]   |
[INFO] [stdout] 6 |     pub fn function() {
[INFO] [stdout]   |            ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trailing semicolon in macro used in expression position
[INFO] [stdout]   --> src/9.rs:6:27
[INFO] [stdout]    |
[INFO] [stdout] 6  |         println!("Hello!");
[INFO] [stdout]    |                           ^
[INFO] [stdout] ...
[INFO] [stdout] 12 |     say_hello!()
[INFO] [stdout]    |     ------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(semicolon_in_expressions_from_macros)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79813 <https://github.com/rust-lang/rust/issues/79813>
[INFO] [stdout]    = note: macro invocations at the end of a block are treated as expressions
[INFO] [stdout]    = note: to ignore the value produced by the macro, add a semicolon after the invocation of `say_hello`
[INFO] [stdout]    = note: this warning originates in the macro `say_hello` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/16_10.rs:6:45
[INFO] [stdout]   |
[INFO] [stdout] 6 | type Result<T> = std::result::Result<T, Box<error::Error>>;
[INFO] [stdout]   |                                             ^^^^^^^^^^^^ help: use `dyn`: `dyn error::Error`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]   = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/16_10.rs:39:32
[INFO] [stdout]    |
[INFO] [stdout] 39 |     fn cause(*self) -> Option<&error::Error> {
[INFO] [stdout]    |                                ^^^^^^^^^^^^ help: use `dyn`: `dyn error::Error`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0106]: missing lifetime specifier
[INFO] [stdout]   --> src/16_10.rs:39:31
[INFO] [stdout]    |
[INFO] [stdout] 39 |     fn cause(*self) -> Option<&error::Error> {
[INFO] [stdout]    |                               ^ expected named lifetime parameter
[INFO] [stdout]    |
[INFO] [stdout]    = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from
[INFO] [stdout] help: consider using the `'static` lifetime
[INFO] [stdout]    |
[INFO] [stdout] 39 |     fn cause(*self) -> Option<&'static error::Error> {
[INFO] [stdout]    |                               ~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0106`.
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/18_4_2.rs:20:70
[INFO] [stdout]    |
[INFO] [stdout] 20 |         Err(why) => panic!("couldn't create {}: {}", display, Error::description(&why)),
[INFO] [stdout]    |                                                                      ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::iter`
[INFO] [stdout]   --> src/9_4.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     use std::iter;
[INFO] [stdout]    |         ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/18_4_2.rs:29:20
[INFO] [stdout]    |
[INFO] [stdout] 29 |             Error::description(&why)
[INFO] [stdout]    |                    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0601]: `main` function not found in crate `9_4`
[INFO] [stdout]   --> src/9_4.rs:1:1
[INFO] [stdout]    |
[INFO] [stdout] 1  | / use std::ops::{Add, Mul, Sub};
[INFO] [stdout] 2  | |
[INFO] [stdout] 3  | | macro_rules! assert_equal_len {
[INFO] [stdout] 4  | |     // `tt`（トークン木）識別子は演算子とトークン用の識別子です。
[INFO] [stdout] ...  |
[INFO] [stdout] 57 | |     test!(sub_assign, 3u32, 2u32, 1u32);
[INFO] [stdout] 58 | | }
[INFO] [stdout]    | |_^ consider adding a `main` function to `src/9_4.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `x`
[INFO] [stdout]  --> src/14_4_4.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     x: &'a i32,
[INFO] [stdout]   |     ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> src/14_4_4.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     y: &'a i32,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/17_5_1.rs:48:32
[INFO] [stdout]    |
[INFO] [stdout] 48 |               Err(why) => panic!(match why {
[INFO] [stdout]    |  ________________________________^
[INFO] [stdout] 49 | |                 MathError::NegativeLogarithm => "logarithm of negative number",
[INFO] [stdout] 50 | |                 MathError::DivisionByZero => "division by zero",
[INFO] [stdout] 51 | |                 MathError::NegativeSquareRoot => "square root of negative number",
[INFO] [stdout] 52 | |             }),
[INFO] [stdout]    | |_____________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout]    = note: this usage of panic!() is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout] help: add a "{}" format string to Display the message
[INFO] [stdout]    |
[INFO] [stdout] 48 |             Err(why) => panic!("{}", match why {
[INFO] [stdout]    |                                +++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `display`
[INFO] [stdout]  --> src/18_3.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let display = path.display();
[INFO] [stdout]   |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_display`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/18_5_1.rs:14:60
[INFO] [stdout]    |
[INFO] [stdout] 14 |         Err(why) => panic!("couldn't spawn wc: {}", Error::description(&why)),
[INFO] [stdout]    |                                                            ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Structure`
[INFO] [stdout]   --> src/1_2.rs:27:12
[INFO] [stdout]    |
[INFO] [stdout] 27 |     struct Structure(i32);
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/18_5_1.rs:23:69
[INFO] [stdout]    |
[INFO] [stdout] 23 |         Err(why) => panic!("couldn't write to wc stdin: {}", Error::description(&why)),
[INFO] [stdout]    |                                                                     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/18_5_1.rs:31:66
[INFO] [stdout]    |
[INFO] [stdout] 31 |         Err(why) => panic!("couldn't read wc stdout: {}", Error::description(&why)),
[INFO] [stdout]    |                                                                  ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "af31d15578374b63c449eb1999c40412c787b2ac11dd84834fbcb7b96e5d8d9e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "af31d15578374b63c449eb1999c40412c787b2ac11dd84834fbcb7b96e5d8d9e", kill_on_drop: false }`
[INFO] [stdout] af31d15578374b63c449eb1999c40412c787b2ac11dd84834fbcb7b96e5d8d9e