[INFO] cloning repository https://github.com/kewalkhondekar25/Rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kewalkhondekar25/Rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkewalkhondekar25%2FRust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkewalkhondekar25%2FRust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f2f01c9d8b7cb414f85413d0b9323f9a5c063575
[INFO] checking kewalkhondekar25/Rust against master#b2f1ccf524a3a4cf9c34545167cc23b659cf1cbd for pr-155501
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkewalkhondekar25%2FRust" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/kewalkhondekar25/Rust
[INFO] finished tweaking git repo https://github.com/kewalkhondekar25/Rust
[INFO] tweaked toml for git repo https://github.com/kewalkhondekar25/Rust written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/kewalkhondekar25/Rust on toolchain b2f1ccf524a3a4cf9c34545167cc23b659cf1cbd
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b2f1ccf524a3a4cf9c34545167cc23b659cf1cbd" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/kewalkhondekar25/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" "+b2f1ccf524a3a4cf9c34545167cc23b659cf1cbd" "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-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+b2f1ccf524a3a4cf9c34545167cc23b659cf1cbd" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] dc712d7de4f13ad60d29cdf840d6900a7fa8bc3749104a824da1ba552c3ca32f
[INFO] running `Command { std: "docker" "start" "-a" "dc712d7de4f13ad60d29cdf840d6900a7fa8bc3749104a824da1ba552c3ca32f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dc712d7de4f13ad60d29cdf840d6900a7fa8bc3749104a824da1ba552c3ca32f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dc712d7de4f13ad60d29cdf840d6900a7fa8bc3749104a824da1ba552c3ca32f", kill_on_drop: false }`
[INFO] [stdout] dc712d7de4f13ad60d29cdf840d6900a7fa8bc3749104a824da1ba552c3ca32f
[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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+b2f1ccf524a3a4cf9c34545167cc23b659cf1cbd" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4e42373f501a78474d96c680f693a0b2a352041ac376c7b0cd9ff5e31a168d63
[INFO] running `Command { std: "docker" "start" "-a" "4e42373f501a78474d96c680f693a0b2a352041ac376c7b0cd9ff5e31a168d63", kill_on_drop: false }`
[INFO] [stderr]     Checking learning-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: value assigned to `x` is never read
[INFO] [stdout]  --> src/_04_mutability/mod.rs:7:22
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let mut x: u32 = 69;
[INFO] [stdout]   |                      ^^ this value is reassigned later and never used
[INFO] [stdout] 8 |     x = 70;
[INFO] [stdout]   |     ------ `x` is overwritten here before the previous value is read
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/_07_borrowing/mod.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 |    let mut x = String::from("Hello");
[INFO] [stdout]    |        ----^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `x` is never read
[INFO] [stdout]  --> src/_04_mutability/mod.rs:7:22
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let mut x: u32 = 69;
[INFO] [stdout]   |                      ^^ this value is reassigned later and never used
[INFO] [stdout] 8 |     x = 70;
[INFO] [stdout]   |     ------ `x` is overwritten here before the previous value is read
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/_07_borrowing/mod.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 |    let mut x = String::from("Hello");
[INFO] [stdout]    |        ----^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.19s
[INFO] running `Command { std: "docker" "inspect" "4e42373f501a78474d96c680f693a0b2a352041ac376c7b0cd9ff5e31a168d63", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4e42373f501a78474d96c680f693a0b2a352041ac376c7b0cd9ff5e31a168d63", kill_on_drop: false }`
[INFO] [stdout] 4e42373f501a78474d96c680f693a0b2a352041ac376c7b0cd9ff5e31a168d63