[INFO] cloning repository https://github.com/fteychene/rust-error-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/fteychene/rust-error-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffteychene%2Frust-error-playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffteychene%2Frust-error-playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] fa8ce5306515ca1d2c77d022d760ab7c00360f86
[INFO] checking fteychene/rust-error-playground against master#22572d0994593197593e2a1b7b18d720a9a349a7 for pr-126452-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffteychene%2Frust-error-playground" "/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/fteychene/rust-error-playground on toolchain 22572d0994593197593e2a1b7b18d720a9a349a7
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+22572d0994593197593e2a1b7b18d720a9a349a7" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/fteychene/rust-error-playground
[INFO] finished tweaking git repo https://github.com/fteychene/rust-error-playground
[INFO] tweaked toml for git repo https://github.com/fteychene/rust-error-playground written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/fteychene/rust-error-playground 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" "+22572d0994593197593e2a1b7b18d720a9a349a7" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+22572d0994593197593e2a1b7b18d720a9a349a7" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8274449478def3dabd3314be154dddb9eca97aaa43a1b6075fed6e8126b1813b
[INFO] running `Command { std: "docker" "start" "-a" "8274449478def3dabd3314be154dddb9eca97aaa43a1b6075fed6e8126b1813b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8274449478def3dabd3314be154dddb9eca97aaa43a1b6075fed6e8126b1813b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8274449478def3dabd3314be154dddb9eca97aaa43a1b6075fed6e8126b1813b", kill_on_drop: false }`
[INFO] [stdout] 8274449478def3dabd3314be154dddb9eca97aaa43a1b6075fed6e8126b1813b
[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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+22572d0994593197593e2a1b7b18d720a9a349a7" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9edf94135cf267a90ab599717cda2f004a06646f2784a2564f469c13862587d5
[INFO] running `Command { std: "docker" "start" "-a" "9edf94135cf267a90ab599717cda2f004a06646f2784a2564f469c13862587d5", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]     Checking regex-syntax v0.6.12
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking aho-corasick v0.7.6
[INFO] [stderr]     Checking regex v1.3.1
[INFO] [stderr]     Checking vanilla v0.1.0 (/opt/rustwide/workdir/vanilla)
[INFO] [stderr]     Checking vanillacustom v0.1.0 (/opt/rustwide/workdir/vanillacustom)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> vanilla/src/main.rs:34:18
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn remove_header(mut chapters: Vec<String>) -> Result<Vec<String>, Box<dyn Error>> {
[INFO] [stdout]    |                  ----^^^^^^^^
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> vanilla/src/main.rs:34:18
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn remove_header(mut chapters: Vec<String>) -> Result<Vec<String>, Box<dyn Error>> {
[INFO] [stdout]    |                  ----^^^^^^^^
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` 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` profile [unoptimized + debuginfo] target(s) in 2.89s
[INFO] running `Command { std: "docker" "inspect" "9edf94135cf267a90ab599717cda2f004a06646f2784a2564f469c13862587d5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9edf94135cf267a90ab599717cda2f004a06646f2784a2564f469c13862587d5", kill_on_drop: false }`
[INFO] [stdout] 9edf94135cf267a90ab599717cda2f004a06646f2784a2564f469c13862587d5
[INFO] checking fteychene/rust-error-playground against try#6289438dbad80b1a0029c66dd3f6abf57c2c51be for pr-126452-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffteychene%2Frust-error-playground" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/fteychene/rust-error-playground on toolchain 6289438dbad80b1a0029c66dd3f6abf57c2c51be
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/fteychene/rust-error-playground
[INFO] finished tweaking git repo https://github.com/fteychene/rust-error-playground
[INFO] tweaked toml for git repo https://github.com/fteychene/rust-error-playground written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/fteychene/rust-error-playground 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" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 398b816d699f2b1fdaa6db8379905fd3f816e8898ad563e2f46218421aca0b3e
[INFO] running `Command { std: "docker" "start" "-a" "398b816d699f2b1fdaa6db8379905fd3f816e8898ad563e2f46218421aca0b3e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "398b816d699f2b1fdaa6db8379905fd3f816e8898ad563e2f46218421aca0b3e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "398b816d699f2b1fdaa6db8379905fd3f816e8898ad563e2f46218421aca0b3e", kill_on_drop: false }`
[INFO] [stdout] 398b816d699f2b1fdaa6db8379905fd3f816e8898ad563e2f46218421aca0b3e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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" "-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 16e1fed450d9de2bef3176b9f899d3d780423e28ea2a7c07b61e60f7c2d726d4
[INFO] running `Command { std: "docker" "start" "-a" "16e1fed450d9de2bef3176b9f899d3d780423e28ea2a7c07b61e60f7c2d726d4", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]     Checking regex-syntax v0.6.12
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking aho-corasick v0.7.6
[INFO] [stderr]     Checking regex v1.3.1
[INFO] [stderr]     Checking vanilla v0.1.0 (/opt/rustwide/workdir/vanilla)
[INFO] [stderr]     Checking vanillacustom v0.1.0 (/opt/rustwide/workdir/vanillacustom)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> vanilla/src/main.rs:34:18
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn remove_header(mut chapters: Vec<String>) -> Result<Vec<String>, Box<dyn Error>> {
[INFO] [stdout]    |                  ----^^^^^^^^
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> vanilla/src/main.rs:34:18
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn remove_header(mut chapters: Vec<String>) -> Result<Vec<String>, Box<dyn Error>> {
[INFO] [stdout]    |                  ----^^^^^^^^
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` 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` profile [unoptimized + debuginfo] target(s) in 2.26s
[INFO] running `Command { std: "docker" "inspect" "16e1fed450d9de2bef3176b9f899d3d780423e28ea2a7c07b61e60f7c2d726d4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "16e1fed450d9de2bef3176b9f899d3d780423e28ea2a7c07b61e60f7c2d726d4", kill_on_drop: false }`
[INFO] [stdout] 16e1fed450d9de2bef3176b9f899d3d780423e28ea2a7c07b61e60f7c2d726d4