[INFO] cloning repository https://github.com/special187/exercise-concurrency
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/special187/exercise-concurrency" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspecial187%2Fexercise-concurrency", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspecial187%2Fexercise-concurrency'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a27325fbb4ba5d3cd151dae49f0dd340034e8b4e
[INFO] checking special187/exercise-concurrency against master#22572d0994593197593e2a1b7b18d720a9a349a7 for pr-126452-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspecial187%2Fexercise-concurrency" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/special187/exercise-concurrency 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/special187/exercise-concurrency
[INFO] finished tweaking git repo https://github.com/special187/exercise-concurrency
[INFO] tweaked toml for git repo https://github.com/special187/exercise-concurrency written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/special187/exercise-concurrency 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] [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-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 11ba2ef04b961f176b52bfd6f81bb5c7ff15d7aa78ea00a1ab35072a10e0ae0f
[INFO] running `Command { std: "docker" "start" "-a" "11ba2ef04b961f176b52bfd6f81bb5c7ff15d7aa78ea00a1ab35072a10e0ae0f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "11ba2ef04b961f176b52bfd6f81bb5c7ff15d7aa78ea00a1ab35072a10e0ae0f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "11ba2ef04b961f176b52bfd6f81bb5c7ff15d7aa78ea00a1ab35072a10e0ae0f", kill_on_drop: false }`
[INFO] [stdout] 11ba2ef04b961f176b52bfd6f81bb5c7ff15d7aa78ea00a1ab35072a10e0ae0f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 59915b8bc5caec691806790da03bfb7ee781030e7cdf07f0598098fec9931fd7
[INFO] running `Command { std: "docker" "start" "-a" "59915b8bc5caec691806790da03bfb7ee781030e7cdf07f0598098fec9931fd7", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.154
[INFO] [stderr]    Compiling proc-macro2 v1.0.81
[INFO] [stderr]     Checking regex-syntax v0.6.29
[INFO] [stderr]     Checking regex-syntax v0.8.3
[INFO] [stderr]     Checking log v0.4.21
[INFO] [stderr]    Compiling anyhow v1.0.82
[INFO] [stderr]     Checking thread_local v1.1.8
[INFO] [stderr]     Checking hashbrown v0.14.5
[INFO] [stderr]     Checking oneshot v0.1.6
[INFO] [stderr]     Checking tracing-log v0.2.0
[INFO] [stderr]    Compiling quote v1.0.36
[INFO] [stderr]    Compiling syn v2.0.60
[INFO] [stderr]     Checking getrandom v0.2.14
[INFO] [stderr]     Checking num_cpus v1.16.0
[INFO] [stderr]     Checking mio v0.8.11
[INFO] [stderr]     Checking socket2 v0.5.7
[INFO] [stderr]     Checking parking_lot_core v0.9.10
[INFO] [stderr]     Checking regex-automata v0.4.6
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking dashmap v5.5.3
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking regex-automata v0.1.10
[INFO] [stderr]     Checking matchers v0.1.0
[INFO] [stderr]     Checking regex v1.10.4
[INFO] [stderr]    Compiling tracing-attributes v0.1.27
[INFO] [stderr]    Compiling tokio-macros v2.2.0
[INFO] [stderr]     Checking tokio v1.37.0
[INFO] [stderr]     Checking tracing v0.1.40
[INFO] [stderr]     Checking tracing-subscriber v0.3.18
[INFO] [stderr]     Checking concurrency v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 9.87s
[INFO] running `Command { std: "docker" "inspect" "59915b8bc5caec691806790da03bfb7ee781030e7cdf07f0598098fec9931fd7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "59915b8bc5caec691806790da03bfb7ee781030e7cdf07f0598098fec9931fd7", kill_on_drop: false }`
[INFO] [stdout] 59915b8bc5caec691806790da03bfb7ee781030e7cdf07f0598098fec9931fd7
[INFO] checking special187/exercise-concurrency against try#6289438dbad80b1a0029c66dd3f6abf57c2c51be for pr-126452-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspecial187%2Fexercise-concurrency" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/special187/exercise-concurrency 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/special187/exercise-concurrency
[INFO] finished tweaking git repo https://github.com/special187/exercise-concurrency
[INFO] tweaked toml for git repo https://github.com/special187/exercise-concurrency written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/special187/exercise-concurrency 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] [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-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 7e5ca5950c26a8c69eaa64f39c2c5e36903bbe881e6df2d91ba2b753a87b96c5
[INFO] running `Command { std: "docker" "start" "-a" "7e5ca5950c26a8c69eaa64f39c2c5e36903bbe881e6df2d91ba2b753a87b96c5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7e5ca5950c26a8c69eaa64f39c2c5e36903bbe881e6df2d91ba2b753a87b96c5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7e5ca5950c26a8c69eaa64f39c2c5e36903bbe881e6df2d91ba2b753a87b96c5", kill_on_drop: false }`
[INFO] [stdout] 7e5ca5950c26a8c69eaa64f39c2c5e36903bbe881e6df2d91ba2b753a87b96c5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] f47913afc28876097ec3b2554d10a0470845981b138dfc9a6e66575239fc65c0
[INFO] running `Command { std: "docker" "start" "-a" "f47913afc28876097ec3b2554d10a0470845981b138dfc9a6e66575239fc65c0", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.154
[INFO] [stderr]    Compiling proc-macro2 v1.0.81
[INFO] [stderr]     Checking regex-syntax v0.6.29
[INFO] [stderr]     Checking regex-syntax v0.8.3
[INFO] [stderr]     Checking log v0.4.21
[INFO] [stderr]    Compiling anyhow v1.0.82
[INFO] [stderr]     Checking thread_local v1.1.8
[INFO] [stderr]     Checking hashbrown v0.14.5
[INFO] [stderr]     Checking oneshot v0.1.6
[INFO] [stderr]     Checking tracing-log v0.2.0
[INFO] [stderr]    Compiling quote v1.0.36
[INFO] [stderr]    Compiling syn v2.0.60
[INFO] [stderr]     Checking getrandom v0.2.14
[INFO] [stderr]     Checking socket2 v0.5.7
[INFO] [stderr]     Checking num_cpus v1.16.0
[INFO] [stderr]     Checking mio v0.8.11
[INFO] [stderr]     Checking parking_lot_core v0.9.10
[INFO] [stderr]     Checking regex-automata v0.4.6
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking dashmap v5.5.3
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking regex-automata v0.1.10
[INFO] [stderr]     Checking regex v1.10.4
[INFO] [stderr]     Checking matchers v0.1.0
[INFO] [stderr]    Compiling tracing-attributes v0.1.27
[INFO] [stderr]    Compiling tokio-macros v2.2.0
[INFO] [stderr]     Checking tokio v1.37.0
[INFO] [stderr]     Checking tracing v0.1.40
[INFO] [stderr]     Checking tracing-subscriber v0.3.18
[INFO] [stderr]     Checking concurrency v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 13.77s
[INFO] running `Command { std: "docker" "inspect" "f47913afc28876097ec3b2554d10a0470845981b138dfc9a6e66575239fc65c0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f47913afc28876097ec3b2554d10a0470845981b138dfc9a6e66575239fc65c0", kill_on_drop: false }`
[INFO] [stdout] f47913afc28876097ec3b2554d10a0470845981b138dfc9a6e66575239fc65c0