[INFO] cloning repository https://github.com/valekar/rust-book
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/valekar/rust-book" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvalekar%2Frust-book", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvalekar%2Frust-book'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 2eeae0ed967ea63e698198235aa39cf767ba7851
[INFO] checking valekar/rust-book against try#39e1293fce4b650061e85dda88aa428f726a8444 for pr-88041
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvalekar%2Frust-book" "/workspace/builds/worker-104/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-104/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/valekar/rust-book on toolchain 39e1293fce4b650061e85dda88aa428f726a8444
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/valekar/rust-book
[INFO] finished tweaking git repo https://github.com/valekar/rust-book
[INFO] tweaked toml for git repo https://github.com/valekar/rust-book written to /workspace/builds/worker-104/source/Cargo.toml
[INFO] crate git repo https://github.com/valekar/rust-book already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "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-104/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e21f00b38d7551a42615eca07c7641167b555e7934ac233e23c923f81d991c27
[INFO] running `Command { std: "docker" "start" "-a" "e21f00b38d7551a42615eca07c7641167b555e7934ac233e23c923f81d991c27", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e21f00b38d7551a42615eca07c7641167b555e7934ac233e23c923f81d991c27", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e21f00b38d7551a42615eca07c7641167b555e7934ac233e23c923f81d991c27", kill_on_drop: false }`
[INFO] [stdout] e21f00b38d7551a42615eca07c7641167b555e7934ac233e23c923f81d991c27
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 248db4637a99cb3aa11e9e2c44b3e100a174a8b0e45770c27f09e2580e8476d3
[INFO] running `Command { std: "docker" "start" "-a" "248db4637a99cb3aa11e9e2c44b3e100a174a8b0e45770c27f09e2580e8476d3", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.98
[INFO] [stderr]     Checking chap-4 v0.1.0 (/opt/rustwide/workdir/chap-4)
[INFO] [stderr]     Checking chap-1 v0.1.0 (/opt/rustwide/workdir/chap-1)
[INFO] [stderr]     Checking chap-3 v0.1.0 (/opt/rustwide/workdir/chap-3)
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]   --> chap-4/src/main.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let s3 = &mut s1;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s4`
[INFO] [stdout]   --> chap-4/src/main.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let s4 = &mut s1;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s4`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]   --> chap-4/src/main.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let s3 = &mut s1;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s4`
[INFO] [stdout]   --> chap-4/src/main.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let s4 = &mut s1;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s4`
[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] [stderr]     Checking getrandom v0.2.3
[INFO] [stderr]     Checking rand_core v0.6.3
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.4
[INFO] [stderr]     Checking chap-2 v0.1.0 (/opt/rustwide/workdir/chap-2)
[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> chap-2/src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> chap-2/src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[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]     Finished dev [unoptimized + debuginfo] target(s) in 5.32s
[INFO] running `Command { std: "docker" "inspect" "248db4637a99cb3aa11e9e2c44b3e100a174a8b0e45770c27f09e2580e8476d3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "248db4637a99cb3aa11e9e2c44b3e100a174a8b0e45770c27f09e2580e8476d3", kill_on_drop: false }`
[INFO] [stdout] 248db4637a99cb3aa11e9e2c44b3e100a174a8b0e45770c27f09e2580e8476d3