[INFO] cloning repository https://github.com/leecobaby/study-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/leecobaby/study-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fleecobaby%2Fstudy-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fleecobaby%2Fstudy-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d7cb5e178d0d2d6794201af8b33d067ab635bef3
[INFO] testing leecobaby/study-rust against master#733b47ea4b1b86216f14ef56e49440c33933f230+rustflags=-Copt-level=3 for pr-138759-retry
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fleecobaby%2Fstudy-rust" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/leecobaby/study-rust
[INFO] finished tweaking git repo https://github.com/leecobaby/study-rust
[INFO] tweaked toml for git repo https://github.com/leecobaby/study-rust written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/leecobaby/study-rust on toolchain 733b47ea4b1b86216f14ef56e49440c33933f230
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/leecobaby/study-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: unused manifest key: profiles
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ff6fc9f91fb54a474e1f02339494312b0b70ee75aa84eb6160116d104e9e461e
[INFO] running `Command { std: "docker" "start" "-a" "ff6fc9f91fb54a474e1f02339494312b0b70ee75aa84eb6160116d104e9e461e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ff6fc9f91fb54a474e1f02339494312b0b70ee75aa84eb6160116d104e9e461e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ff6fc9f91fb54a474e1f02339494312b0b70ee75aa84eb6160116d104e9e461e", kill_on_drop: false }`
[INFO] [stdout] ff6fc9f91fb54a474e1f02339494312b0b70ee75aa84eb6160116d104e9e461e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/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 -Copt-level=3" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7bf088668eaec8cf9f3c64536356eca11f964f388091857634130b84ea95f648
[INFO] running `Command { std: "docker" "start" "-a" "7bf088668eaec8cf9f3c64536356eca11f964f388091857634130b84ea95f648", kill_on_drop: false }`
[INFO] [stderr] warning: unused manifest key: profiles
[INFO] [stderr]    Compiling libc v0.2.139
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand v0.5.6
[INFO] [stderr]    Compiling study_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> src/bin/19-4.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let v = Status::Value(3);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `list_of_statuses`
[INFO] [stdout]   --> src/bin/19-4.rs:24:9
[INFO] [stdout]    |
[INFO] [stdout] 24 |     let list_of_statuses: Vec<Status> = (0u32..20).map(Status::Value).collect();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_list_of_statuses`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/bin/19-4.rs:17:15
[INFO] [stdout]    |
[INFO] [stdout] 17 |         Value(u32),
[INFO] [stdout]    |         ----- ^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 17 -         Value(u32),
[INFO] [stdout] 17 +         Value(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Stop` is never constructed
[INFO] [stdout]   --> src/bin/19-4.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     enum Status {
[INFO] [stdout]    |          ------ variant in this enum
[INFO] [stdout] 17 |         Value(u32),
[INFO] [stdout] 18 |         Stop,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `returns_closure` is never used
[INFO] [stdout]   --> src/bin/19-4.rs:39:4
[INFO] [stdout]    |
[INFO] [stdout] 39 | fn returns_closure() -> Box<dyn Fn(i32) -> i32> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0004]: non-exhaustive patterns: `Message::Quit`, `Message::Move { .. }`, `Message::Write(_)` and 1 more not covered
[INFO] [stdout]    --> src/bin/18-3.rs:145:11
[INFO] [stdout]     |
[INFO] [stdout] 145 |     match msg {
[INFO] [stdout]     |           ^^^ patterns `Message::Quit`, `Message::Move { .. }`, `Message::Write(_)` and 1 more not covered
[INFO] [stdout]     |
[INFO] [stdout] note: `Message` defined here
[INFO] [stdout]    --> src/bin/18-3.rs:166:6
[INFO] [stdout]     |
[INFO] [stdout] 166 | enum Message {
[INFO] [stdout]     |      ^^^^^^^
[INFO] [stdout] 167 |     Quit,
[INFO] [stdout]     |     ---- not covered
[INFO] [stdout] 168 |     Move { x: i32, y: i32 },
[INFO] [stdout]     |     ---- not covered
[INFO] [stdout] 169 |     Write(String),
[INFO] [stdout]     |     ----- not covered
[INFO] [stdout] 170 |     ChangeColor(i32, i32, i32),
[INFO] [stdout]     |     ----------- not covered
[INFO] [stdout]     = note: the matched value is of type `Message`
[INFO] [stdout] help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern as shown, or multiple match arms
[INFO] [stdout]     |
[INFO] [stdout] 157 ~         },
[INFO] [stdout] 158 +         _ => todo!()
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0004`.
[INFO] [stdout] 
[INFO] [stdout] error[E0601]: `main` function not found in crate `pool`
[INFO] [stdout]   --> src/bin/pool.rs:22:2
[INFO] [stdout]    |
[INFO] [stdout] 22 | }
[INFO] [stdout]    |  ^ consider adding a `main` function to `src/bin/pool.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> src/bin/pool.rs:17:30
[INFO] [stdout]    |
[INFO] [stdout] 17 |     pub fn execute<F>(&self, f: F)
[INFO] [stdout]    |                              ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0382]: borrow of moved value: `x`
[INFO] [stdout]   --> src/bin/13-4.rs:17:40
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let x = vec![1, 2, 3];
[INFO] [stdout]    |         - move occurs because `x` has type `Vec<i32>`, which does not implement the `Copy` trait
[INFO] [stdout] 14 |
[INFO] [stdout] 15 |     let equal_to_x = move |z| z == x;
[INFO] [stdout]    |                      --------      - variable moved due to use in closure
[INFO] [stdout]    |                      |
[INFO] [stdout]    |                      value moved into closure here
[INFO] [stdout] 16 |
[INFO] [stdout] 17 |     println!("can't use x here: {:?}", x);
[INFO] [stdout]    |                                        ^ value borrowed here after move
[INFO] [stdout]    |
[INFO] [stdout]    = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: consider cloning the value before moving it into the closure
[INFO] [stdout]    |
[INFO] [stdout] 15 ~     let value = x.clone();
[INFO] [stdout] 16 ~     let equal_to_x = move |z| z == value;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0382`.
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `study_rust` (bin "13-4") due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `study_rust` (bin "18-3") due to 1 previous error
[INFO] [stdout] error[E0381]: used binding `buffer` isn't initialized
[INFO] [stdout]   --> src/bin/13-10.rs:12:18
[INFO] [stdout]    |
[INFO] [stdout] 8  |     let buffer: &mut [i32];
[INFO] [stdout]    |         ------ binding declared here but left uninitialized
[INFO] [stdout] ...
[INFO] [stdout] 12 |     for i in 12..buffer.len() {
[INFO] [stdout]    |                  ^^^^^^ `*buffer` used here but it isn't initialized
[INFO] [stdout]    |
[INFO] [stdout] help: consider assigning a value
[INFO] [stdout]    |
[INFO] [stdout] 8  |     let buffer: &mut [i32] = &mut [];
[INFO] [stdout]    |                            +++++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0601]: `main` function not found in crate `11_8`
[INFO] [stdout]   --> src/bin/11-8.rs:19:2
[INFO] [stdout]    |
[INFO] [stdout] 19 | }
[INFO] [stdout]    |  ^ consider adding a `main` function to `src/bin/11-8.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0381]: used binding `coefficients` isn't initialized
[INFO] [stdout]   --> src/bin/13-10.rs:13:26
[INFO] [stdout]    |
[INFO] [stdout] 9  |     let coefficients: [i64; 12];
[INFO] [stdout]    |         ------------ binding declared here but left uninitialized
[INFO] [stdout] ...
[INFO] [stdout] 13 |         let prediction = coefficients
[INFO] [stdout]    |                          ^^^^^^^^^^^^ `coefficients` used here but it isn't initialized
[INFO] [stdout]    |
[INFO] [stdout] help: consider assigning a value
[INFO] [stdout]    |
[INFO] [stdout] 9  |     let coefficients: [i64; 12] = [42; 12];
[INFO] [stdout]    |                                 ++++++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0381]: used binding `qlp_shift` isn't initialized
[INFO] [stdout]   --> src/bin/13-10.rs:18:16
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let qlp_shift: i16;
[INFO] [stdout]    |         --------- binding declared here but left uninitialized
[INFO] [stdout] ...
[INFO] [stdout] 18 |             >> qlp_shift;
[INFO] [stdout]    |                ^^^^^^^^^ `qlp_shift` used here but it isn't initialized
[INFO] [stdout]    |
[INFO] [stdout] help: consider assigning a value
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let qlp_shift: i16 = 42;
[INFO] [stdout]    |                        ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `OpenOptions`
[INFO] [stdout]  --> src/bin/9-2.rs:3:21
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::fs::{File, OpenOptions};
[INFO] [stdout]   |                     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::io`
[INFO] [stdout]  --> src/bin/9-2.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::io;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0381`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `study_rust` (bin "pool") due to 1 previous error; 1 warning emitted
[INFO] [stdout] error[E0583]: file not found for module `hosting`
[INFO] [stdout]  --> src/bin/demo_module.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub mod hosting;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: to create the module `hosting`, create file "src/bin/demo_module/hosting.rs" or "src/bin/demo_module/hosting/mod.rs"
[INFO] [stdout]   = note: if there is a `mod hosting` elsewhere in the crate already, import it with `use crate::...` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0106]: missing lifetime specifier
[INFO] [stdout]   --> src/bin/4-2.rs:30:16
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn dangle() -> &String { // 编译器会报错
[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, but this is uncommon unless you're returning a borrowed value from a `const` or a `static`
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn dangle() -> &'static String { // 编译器会报错
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] help: instead, you are more likely to want to return an owned value
[INFO] [stdout]    |
[INFO] [stdout] 30 - fn dangle() -> &String { // 编译器会报错
[INFO] [stdout] 30 + fn dangle() -> String { // 编译器会报错
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0583`.
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/bin/9-2.rs:33:9
[INFO] [stdout]    |
[INFO] [stdout] 33 |     let b = match &f {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> src/bin/9-2.rs:67:9
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let f = File::open("hello.txt").unwrap();
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> src/bin/9-2.rs:68:9
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let f = File::open("hello.txt").expect("Failed to open hello.txt");
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0716]: temporary value dropped while borrowed
[INFO] [stdout]   --> src/bin/9-2.rs:37:43
[INFO] [stdout]    |
[INFO] [stdout] 35 |           Err(error) => match error.kind() {
[INFO] [stdout]    |  _______________________-
[INFO] [stdout] 36 | |             // TODO: 局部作用域的借用会出错
[INFO] [stdout] 37 | |             ErrorKind::NotFound => match &File::create("hello.txt") {
[INFO] [stdout]    | |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
[INFO] [stdout] 38 | |                 Ok(fc) => fc,
[INFO] [stdout] 39 | |                 Err(e) => panic!("Tried to create file but there was a problem: {:?}", e),
[INFO] [stdout] 40 | |             },
[INFO] [stdout]    | |             - temporary value is freed at the end of this statement
[INFO] [stdout] ...  |
[INFO] [stdout] 44 | |         },
[INFO] [stdout]    | |_________- borrow later used here
[INFO] [stdout]    |
[INFO] [stdout] help: consider using a `let` binding to create a longer lived value
[INFO] [stdout]    |
[INFO] [stdout] 33 ~     let binding = File::create("hello.txt");
[INFO] [stdout] 34 ~     let b = match &f {
[INFO] [stdout] 35 |         Ok(file) => file,
[INFO] [stdout] 36 |         Err(error) => match error.kind() {
[INFO] [stdout] 37 |             // TODO: 局部作用域的借用会出错
[INFO] [stdout] 38 ~             ErrorKind::NotFound => match &binding {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `study_rust` (bin "13-10") due to 3 previous errors
[INFO] [stderr] error: could not compile `study_rust` (bin "11-8") due to 1 previous error
[INFO] [stdout] For more information about this error, try `rustc --explain E0716`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `study_rust` (bin "9-2") due to 1 previous error; 5 warnings emitted
[INFO] [stderr] error: could not compile `study_rust` (bin "7-6") due to 1 previous error
[INFO] [stdout] For more information about this error, try `rustc --explain E0106`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `study_rust` (bin "4-2") due to 1 previous error
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]  --> src/bin/13-2.rs:7:29
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let n = example_closure(5);
[INFO] [stdout]   |             --------------- ^- help: try using a conversion method: `.to_string()`
[INFO] [stdout]   |             |               |
[INFO] [stdout]   |             |               expected `String`, found integer
[INFO] [stdout]   |             arguments to this function are incorrect
[INFO] [stdout]   |
[INFO] [stdout] note: expected because the closure was earlier called with an argument of type `String`
[INFO] [stdout]  --> src/bin/13-2.rs:4:29
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let s = example_closure(String::from("hello"));
[INFO] [stdout]   |             --------------- ^^^^^^^^^^^^^^^^^^^^^ expected because this argument is of type `String`
[INFO] [stdout]   |             |
[INFO] [stdout]   |             in this closure call
[INFO] [stdout] note: closure parameter defined here
[INFO] [stdout]  --> src/bin/13-2.rs:2:28
[INFO] [stdout]   |
[INFO] [stdout] 2 |     let example_closure = |x| x;
[INFO] [stdout]   |                            ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `from` that must be used
[INFO] [stdout]   --> src/bin/10-3.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         String::from("(Read more...)");
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[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] 11 |         let _ = String::from("(Read more...)");
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0308`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `study_rust` (bin "13-2") due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "7bf088668eaec8cf9f3c64536356eca11f964f388091857634130b84ea95f648", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7bf088668eaec8cf9f3c64536356eca11f964f388091857634130b84ea95f648", kill_on_drop: false }`
[INFO] [stdout] 7bf088668eaec8cf9f3c64536356eca11f964f388091857634130b84ea95f648
