[INFO] cloning repository https://github.com/iamoperand/linked-list-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/iamoperand/linked-list-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiamoperand%2Flinked-list-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiamoperand%2Flinked-list-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] fad29c8ad02faa36e836ee691d05860cf02d3adc
[INFO] checking iamoperand/linked-list-rust against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiamoperand%2Flinked-list-rust" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/iamoperand/linked-list-rust
[INFO] finished tweaking git repo https://github.com/iamoperand/linked-list-rust
[INFO] tweaked toml for git repo https://github.com/iamoperand/linked-list-rust written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/iamoperand/linked-list-rust on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/iamoperand/linked-list-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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 259d802f11e1d038cb5f0f27cbd4be8b007cf8e20a14e5106251d1eda0c77f0e
[INFO] running `Command { std: "docker" "start" "-a" "259d802f11e1d038cb5f0f27cbd4be8b007cf8e20a14e5106251d1eda0c77f0e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "259d802f11e1d038cb5f0f27cbd4be8b007cf8e20a14e5106251d1eda0c77f0e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "259d802f11e1d038cb5f0f27cbd4be8b007cf8e20a14e5106251d1eda0c77f0e", kill_on_drop: false }`
[INFO] [stdout] 259d802f11e1d038cb5f0f27cbd4be8b007cf8e20a14e5106251d1eda0c77f0e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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 -Dunmustuse_in_always_ok" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 003b6e496b1ab262dffd69a02ed60cd166037eadfec52879cfb17b57ae17998e
[INFO] running `Command { std: "docker" "start" "-a" "003b6e496b1ab262dffd69a02ed60cd166037eadfec52879cfb17b57ae17998e", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]     Checking os_str_bytes v6.0.1
[INFO] [stderr]     Checking textwrap v0.15.0
[INFO] [stderr]    Compiling indexmap v1.8.1
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]     Checking clap_lex v0.2.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling clap_derive v3.1.18
[INFO] [stderr]     Checking clap v3.1.18
[INFO] [stderr]     Checking list v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:100:13
[INFO] [stdout]     |
[INFO] [stdout] 100 |         let mut prev_to_target_node = self.get_nth_node_mut(index - 1).unwrap();
[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: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:100:13
[INFO] [stdout]     |
[INFO] [stdout] 100 |         let mut prev_to_target_node = self.get_nth_node_mut(index - 1).unwrap();
[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] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]   --> src/main.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout]  9 | /     /// relative path to the input file
[INFO] [stdout] 10 | |     filepath: String,
[INFO] [stdout]    | |____________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `list` (bin "list" test) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]   --> src/main.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout]  9 | /     /// relative path to the input file
[INFO] [stdout] 10 | |     filepath: String,
[INFO] [stdout]    | |____________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `list` (bin "list") due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "003b6e496b1ab262dffd69a02ed60cd166037eadfec52879cfb17b57ae17998e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "003b6e496b1ab262dffd69a02ed60cd166037eadfec52879cfb17b57ae17998e", kill_on_drop: false }`
[INFO] [stdout] 003b6e496b1ab262dffd69a02ed60cd166037eadfec52879cfb17b57ae17998e