[INFO] fetching crate lab 0.8.1...
[INFO] checking lab-0.8.1 against master#d62d3f7fa9a91d933213cc10e20e740608983f64 for pr-77015
[INFO] extracting crate lab 0.8.1 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate lab 0.8.1 on toolchain d62d3f7fa9a91d933213cc10e20e740608983f64
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate lab 0.8.1
[INFO] finished tweaking crates.io crate lab 0.8.1
[INFO] tweaked toml for crates.io crate lab 0.8.1 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] db2e3d8b88e662c30a363e645011da61cfe414af3a66e4d19e6c9c395c130bbd
[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" "db2e3d8b88e662c30a363e645011da61cfe414af3a66e4d19e6c9c395c130bbd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "db2e3d8b88e662c30a363e645011da61cfe414af3a66e4d19e6c9c395c130bbd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db2e3d8b88e662c30a363e645011da61cfe414af3a66e4d19e6c9c395c130bbd", kill_on_drop: false }`
[INFO] [stdout] db2e3d8b88e662c30a363e645011da61cfe414af3a66e4d19e6c9c395c130bbd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cb4fcfaa5c6f7d4fac18c133d72bd343e6f0c2b3c3eb684f8d7791dc7d5a88b4
[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" "cb4fcfaa5c6f7d4fac18c133d72bd343e6f0c2b3c3eb684f8d7791dc7d5a88b4", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling serde_derive v1.0.116
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]     Checking same-file v1.0.6
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]     Checking lab v0.8.1 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.6
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling rayon v1.4.1
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking serde_cbor v0.11.1
[INFO] [stderr]    Compiling cast v0.2.3
[INFO] [stderr]     Checking tinytemplate v1.1.0
[INFO] [stderr]     Checking walkdir v2.3.1
[INFO] [stderr]     Checking pretty_assertions v0.6.1
[INFO] [stderr]     Checking bstr v0.2.13
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand v0.5.6
[INFO] [stderr]     Checking criterion-plot v0.4.3
[INFO] [stderr]     Checking crossbeam-channel v0.4.4
[INFO] [stderr]     Checking csv v1.1.3
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]    Compiling syn v1.0.42
[INFO] [stderr]     Checking plotters v0.2.15
[INFO] [stderr]     Checking approx v0.3.2
[INFO] [stderr]     Checking rayon-core v1.8.1
[INFO] [stderr]     Checking criterion v0.3.3
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]   --> src/lib.rs:88:1
[INFO] [stdout]    |
[INFO] [stdout] 88 | #[macro_use]
[INFO] [stdout]    | ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]   --> src/lib.rs:91:1
[INFO] [stdout]    |
[INFO] [stdout] 91 | #[macro_use]
[INFO] [stdout]    | ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 55.87s
[INFO] running `Command { std: "docker" "inspect" "cb4fcfaa5c6f7d4fac18c133d72bd343e6f0c2b3c3eb684f8d7791dc7d5a88b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cb4fcfaa5c6f7d4fac18c133d72bd343e6f0c2b3c3eb684f8d7791dc7d5a88b4", kill_on_drop: false }`
[INFO] [stdout] cb4fcfaa5c6f7d4fac18c133d72bd343e6f0c2b3c3eb684f8d7791dc7d5a88b4