[INFO] cloning repository https://github.com/pze/rs-lists-practice
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/pze/rs-lists-practice" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpze%2Frs-lists-practice", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpze%2Frs-lists-practice'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 01821c4c919f62ab370514c2adaca7495c9241f2
[INFO] checking pze/rs-lists-practice against try#4949cf2f817beadb9a248d423b6d55d6d2398ffe for pr-142681
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpze%2Frs-lists-practice" "/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/pze/rs-lists-practice
[INFO] finished tweaking git repo https://github.com/pze/rs-lists-practice
[INFO] tweaked toml for git repo https://github.com/pze/rs-lists-practice written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/pze/rs-lists-practice on toolchain 4949cf2f817beadb9a248d423b6d55d6d2398ffe
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4949cf2f817beadb9a248d423b6d55d6d2398ffe" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/pze/rs-lists-practice 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" "+4949cf2f817beadb9a248d423b6d55d6d2398ffe" "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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+4949cf2f817beadb9a248d423b6d55d6d2398ffe" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 090ef561e1dc3ebd6c1335e7253d7ec35fb1fbffa74ca2da6c4d2c0b82cece5b
[INFO] running `Command { std: "docker" "start" "-a" "090ef561e1dc3ebd6c1335e7253d7ec35fb1fbffa74ca2da6c4d2c0b82cece5b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "090ef561e1dc3ebd6c1335e7253d7ec35fb1fbffa74ca2da6c4d2c0b82cece5b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "090ef561e1dc3ebd6c1335e7253d7ec35fb1fbffa74ca2da6c4d2c0b82cece5b", kill_on_drop: false }`
[INFO] [stdout] 090ef561e1dc3ebd6c1335e7253d7ec35fb1fbffa74ca2da6c4d2c0b82cece5b
[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" "-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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+4949cf2f817beadb9a248d423b6d55d6d2398ffe" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8d013a01c2000b845d794a93068621aea65b93c5662d3bf773f08d7f9411542e
[INFO] running `Command { std: "docker" "start" "-a" "8d013a01c2000b845d794a93068621aea65b93c5662d3bf773f08d7f9411542e", kill_on_drop: false }`
[INFO] [stderr]     Checking rs-lists v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]   --> src/lib.rs:74:17
[INFO] [stdout]    |
[INFO] [stdout] 74 |     pub fn iter(&self) -> Iter<T> {
[INFO] [stdout]    |                 ^^^^^     ------- the lifetime gets resolved as `'_`
[INFO] [stdout]    |                 |
[INFO] [stdout]    |                 this lifetime flows to the output
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]    |
[INFO] [stdout] 74 |     pub fn iter(&self) -> Iter<'_, T> {
[INFO] [stdout]    |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]   --> src/lib.rs:74:17
[INFO] [stdout]    |
[INFO] [stdout] 74 |     pub fn iter(&self) -> Iter<T> {
[INFO] [stdout]    |                 ^^^^^     ------- the lifetime gets resolved as `'_`
[INFO] [stdout]    |                 |
[INFO] [stdout]    |                 this lifetime flows to the output
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]    |
[INFO] [stdout] 74 |     pub fn iter(&self) -> Iter<'_, T> {
[INFO] [stdout]    |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.07s
[INFO] running `Command { std: "docker" "inspect" "8d013a01c2000b845d794a93068621aea65b93c5662d3bf773f08d7f9411542e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8d013a01c2000b845d794a93068621aea65b93c5662d3bf773f08d7f9411542e", kill_on_drop: false }`
[INFO] [stdout] 8d013a01c2000b845d794a93068621aea65b93c5662d3bf773f08d7f9411542e