[INFO] cloning repository https://github.com/nerdrew/rust-self-referential-struct
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/nerdrew/rust-self-referential-struct" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnerdrew%2Frust-self-referential-struct", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnerdrew%2Frust-self-referential-struct'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e8cf708ceb78d9f3ad950cb6f609a7c7a5336b71
[INFO] checking nerdrew/rust-self-referential-struct against master#0d37dca25a51fb900a402c94c8818ad1c2789e30 for pr-77526
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnerdrew%2Frust-self-referential-struct" "/workspace/builds/worker-1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/nerdrew/rust-self-referential-struct on toolchain 0d37dca25a51fb900a402c94c8818ad1c2789e30
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/nerdrew/rust-self-referential-struct
[INFO] finished tweaking git repo https://github.com/nerdrew/rust-self-referential-struct
[INFO] tweaked toml for git repo https://github.com/nerdrew/rust-self-referential-struct written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/nerdrew/rust-self-referential-struct already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 35c3f59f26a109ae008bc579402b94b44b3f3ce8393b1deb0965bcc0670e4b1e
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "35c3f59f26a109ae008bc579402b94b44b3f3ce8393b1deb0965bcc0670e4b1e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "35c3f59f26a109ae008bc579402b94b44b3f3ce8393b1deb0965bcc0670e4b1e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "35c3f59f26a109ae008bc579402b94b44b3f3ce8393b1deb0965bcc0670e4b1e", kill_on_drop: false }`
[INFO] [stdout] 35c3f59f26a109ae008bc579402b94b44b3f3ce8393b1deb0965bcc0670e4b1e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 66dd7c83cecb084963c06654dc9adc1704746c972223606379c8b77052e28772
[INFO] running `Command { std: "docker" "start" "-a" "66dd7c83cecb084963c06654dc9adc1704746c972223606379c8b77052e28772", kill_on_drop: false }`
[INFO] [stderr]     Checking rust-self-referential-struct v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:67:9
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let mut owned = Owned::from("I see you".to_string());
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:67:9
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let mut owned = Owned::from("I see you".to_string());
[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] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.43s
[INFO] running `Command { std: "docker" "inspect" "66dd7c83cecb084963c06654dc9adc1704746c972223606379c8b77052e28772", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "66dd7c83cecb084963c06654dc9adc1704746c972223606379c8b77052e28772", kill_on_drop: false }`
[INFO] [stdout] 66dd7c83cecb084963c06654dc9adc1704746c972223606379c8b77052e28772