[INFO] cloning repository https://github.com/ramandeepbhagat/learn_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ramandeepbhagat/learn_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Framandeepbhagat%2Flearn_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Framandeepbhagat%2Flearn_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e253b3a8e61cf0ec73aee0359e4f626c53c18d63
[INFO] checking ramandeepbhagat/learn_rust against master#ecb170afc878648c3ae355dbd596c8e4b6f7ebdc for pr-139022
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Framandeepbhagat%2Flearn_rust" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ramandeepbhagat/learn_rust on toolchain ecb170afc878648c3ae355dbd596c8e4b6f7ebdc
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ecb170afc878648c3ae355dbd596c8e4b6f7ebdc" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/ramandeepbhagat/learn_rust
[INFO] finished tweaking git repo https://github.com/ramandeepbhagat/learn_rust
[INFO] tweaked toml for git repo https://github.com/ramandeepbhagat/learn_rust written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/ramandeepbhagat/learn_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" "+ecb170afc878648c3ae355dbd596c8e4b6f7ebdc" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:4b26683ee3c49f365255c425c23003cbf4366de097804722c29c5bbbee3624d2" "/opt/rustwide/cargo-home/bin/cargo" "+ecb170afc878648c3ae355dbd596c8e4b6f7ebdc" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c6eec021a1a51a5058d11723f246a0ed2fd55ecfc6aaaabebbf197b0bea27b17
[INFO] running `Command { std: "docker" "start" "-a" "c6eec021a1a51a5058d11723f246a0ed2fd55ecfc6aaaabebbf197b0bea27b17", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c6eec021a1a51a5058d11723f246a0ed2fd55ecfc6aaaabebbf197b0bea27b17", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c6eec021a1a51a5058d11723f246a0ed2fd55ecfc6aaaabebbf197b0bea27b17", kill_on_drop: false }`
[INFO] [stdout] c6eec021a1a51a5058d11723f246a0ed2fd55ecfc6aaaabebbf197b0bea27b17
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:4b26683ee3c49f365255c425c23003cbf4366de097804722c29c5bbbee3624d2" "/opt/rustwide/cargo-home/bin/cargo" "+ecb170afc878648c3ae355dbd596c8e4b6f7ebdc" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1ee674893fab69d9aad5a3bafd8e4ef662ecc69c3120293585c3df2cac403d39
[INFO] running `Command { std: "docker" "start" "-a" "1ee674893fab69d9aad5a3bafd8e4ef662ecc69c3120293585c3df2cac403d39", kill_on_drop: false }`
[INFO] [stderr]     Checking learn_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]   --> src/bin/expressions.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: field `0` is never read
[INFO] [stdout]  --> src/bin/fmt_struct.rs:4:18
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Structure(i32);
[INFO] [stdout]   |        --------- ^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `Structure` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/bin/fmt_struct.rs:7:13
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Deep(Structure);
[INFO] [stdout]   |        ---- ^^^^^^^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `Deep` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]   --> src/bin/expressions.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: field `0` is never read
[INFO] [stdout]  --> src/bin/fmt_struct.rs:4:18
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Structure(i32);
[INFO] [stdout]   |        --------- ^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `Structure` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/bin/fmt_struct.rs:7:13
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Deep(Structure);
[INFO] [stdout]   |        ---- ^^^^^^^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `Deep` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.28s
[INFO] running `Command { std: "docker" "inspect" "1ee674893fab69d9aad5a3bafd8e4ef662ecc69c3120293585c3df2cac403d39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1ee674893fab69d9aad5a3bafd8e4ef662ecc69c3120293585c3df2cac403d39", kill_on_drop: false }`
[INFO] [stdout] 1ee674893fab69d9aad5a3bafd8e4ef662ecc69c3120293585c3df2cac403d39