[INFO] cloning repository https://github.com/jacek-kurlit/learning-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jacek-kurlit/learning-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjacek-kurlit%2Flearning-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjacek-kurlit%2Flearning-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] dde4eb92ab77acda524b88108fb0c06fb23864c5
[INFO] checking jacek-kurlit/learning-rust against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjacek-kurlit%2Flearning-rust" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] removed /workspace/builds/worker-3-tc2/source/rust-toolchain.toml
[INFO] started tweaking git repo https://github.com/jacek-kurlit/learning-rust
[INFO] finished tweaking git repo https://github.com/jacek-kurlit/learning-rust
[INFO] tweaked toml for git repo https://github.com/jacek-kurlit/learning-rust written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/jacek-kurlit/learning-rust on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/jacek-kurlit/learning-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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[ERROR] error running command: no output for 300 seconds
[INFO] checking jacek-kurlit/learning-rust against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjacek-kurlit%2Flearning-rust" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] removed /workspace/builds/worker-3-tc2/source/rust-toolchain.toml
[INFO] started tweaking git repo https://github.com/jacek-kurlit/learning-rust
[INFO] finished tweaking git repo https://github.com/jacek-kurlit/learning-rust
[INFO] tweaked toml for git repo https://github.com/jacek-kurlit/learning-rust written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/jacek-kurlit/learning-rust on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/jacek-kurlit/learning-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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 303c646a059e83081ef4b3b520e48074c993df9b4dbf16688c7ffdc3e62da840
[INFO] running `Command { std: "docker" "start" "-a" "303c646a059e83081ef4b3b520e48074c993df9b4dbf16688c7ffdc3e62da840", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "303c646a059e83081ef4b3b520e48074c993df9b4dbf16688c7ffdc3e62da840", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "303c646a059e83081ef4b3b520e48074c993df9b4dbf16688c7ffdc3e62da840", kill_on_drop: false }`
[INFO] [stdout] 303c646a059e83081ef4b3b520e48074c993df9b4dbf16688c7ffdc3e62da840
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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 -Dunmustuse_in_always_ok" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2009f8736bc3f9d9e5e60b13502b6246099d05ffc3df756f1ceeb3095d432ec7
[INFO] running `Command { std: "docker" "start" "-a" "2009f8736bc3f9d9e5e60b13502b6246099d05ffc3df756f1ceeb3095d432ec7", kill_on_drop: false }`
[INFO] [stderr]     Checking learning_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: expected `{`, found `}`
[INFO] [stdout]   --> src/topics/async_await.rs:73:5
[INFO] [stdout]    |
[INFO] [stdout] 64 |           while while let Ok(stream) = accept.wait  {
[INFO] [stdout]    |  _________-----_-
[INFO] [stdout]    | |         |
[INFO] [stdout]    | |         while parsing the body of this `while` expression
[INFO] [stdout] ...  |
[INFO] [stdout] 72 | |         }
[INFO] [stdout]    | |_________- this `while` condition successfully parsed
[INFO] [stdout] 73 |       });
[INFO] [stdout]    |       ^ expected `{`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: expected item after doc comment
[INFO] [stdout]    --> src/topics/async_await.rs:107:1
[INFO] [stdout]     |
[INFO] [stdout] 103 | / /// What is the difference between std Mutex and tokio Mutex?
[INFO] [stdout] 104 | | /// tokio Mutex is async aware and std Mutex is not
[INFO] [stdout] 105 | | /// std Mutex simply blocks so using it between .await may cause dead locks
[INFO] [stdout] 106 | | /// On the other hand tokio Mutex is much more complex and may need additional time to aquire and
[INFO] [stdout]     | |_________________________________________________________________________________________________- other attributes here
[INFO] [stdout] 107 |   /// unlock mutex
[INFO] [stdout]     |   ^^^^^^^^^^^^^^^^ this doc comment doesn't document anything
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: expected `{`, found `}`
[INFO] [stdout]   --> src/topics/async_await.rs:73:5
[INFO] [stdout]    |
[INFO] [stdout] 64 |           while while let Ok(stream) = accept.wait  {
[INFO] [stdout]    |  _________-----_-
[INFO] [stdout]    | |         |
[INFO] [stdout]    | |         while parsing the body of this `while` expression
[INFO] [stdout] ...  |
[INFO] [stdout] 72 | |         }
[INFO] [stdout]    | |_________- this `while` condition successfully parsed
[INFO] [stdout] 73 |       });
[INFO] [stdout]    |       ^ expected `{`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: expected item after doc comment
[INFO] [stdout]    --> src/topics/async_await.rs:107:1
[INFO] [stdout]     |
[INFO] [stdout] 103 | / /// What is the difference between std Mutex and tokio Mutex?
[INFO] [stdout] 104 | | /// tokio Mutex is async aware and std Mutex is not
[INFO] [stdout] 105 | | /// std Mutex simply blocks so using it between .await may cause dead locks
[INFO] [stdout] 106 | | /// On the other hand tokio Mutex is much more complex and may need additional time to aquire and
[INFO] [stdout]     | |_________________________________________________________________________________________________- other attributes here
[INFO] [stdout] 107 |   /// unlock mutex
[INFO] [stdout]     |   ^^^^^^^^^^^^^^^^ this doc comment doesn't document anything
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `learning_rust` (lib) due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/topics/drop_check.rs:90:13
[INFO] [stdout]    |
[INFO] [stdout] 90 |         let b = Boks::new(UpsiDaisy(&mut z));
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `y` is never read
[INFO] [stdout]   --> src/topics/subtyping.rs:88:21
[INFO] [stdout]    |
[INFO] [stdout] 88 |         let mut y = &*s;
[INFO] [stdout]    |                     ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]   --> src/topics/subtyping.rs:97:13
[INFO] [stdout]    |
[INFO] [stdout] 97 |         let z = vec![&x];
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]    --> src/topics/subtyping.rs:103:13
[INFO] [stdout]     |
[INFO] [stdout] 103 |         let z = vec![TouchDrop(&x)];
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `learning_rust` (lib test) due to 2 previous errors; 4 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "2009f8736bc3f9d9e5e60b13502b6246099d05ffc3df756f1ceeb3095d432ec7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2009f8736bc3f9d9e5e60b13502b6246099d05ffc3df756f1ceeb3095d432ec7", kill_on_drop: false }`
[INFO] [stdout] 2009f8736bc3f9d9e5e60b13502b6246099d05ffc3df756f1ceeb3095d432ec7