[INFO] fetching crate stperf 0.1.4...
[INFO] testing stperf-0.1.4 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate stperf 0.1.4 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate stperf 0.1.4 on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate stperf 0.1.4
[INFO] finished tweaking crates.io crate stperf 0.1.4
[INFO] tweaked toml for crates.io crate stperf 0.1.4 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 13d9ff4e2dee91fee927daf588333605776f922b66ccf1358df8bd78618bf36d
[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" "13d9ff4e2dee91fee927daf588333605776f922b66ccf1358df8bd78618bf36d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "13d9ff4e2dee91fee927daf588333605776f922b66ccf1358df8bd78618bf36d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "13d9ff4e2dee91fee927daf588333605776f922b66ccf1358df8bd78618bf36d", kill_on_drop: false }`
[INFO] [stdout] 13d9ff4e2dee91fee927daf588333605776f922b66ccf1358df8bd78618bf36d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--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] 5101280acc1a53b52c23340eb552962ad38c970b3b9d1888767212d07c614a7a
[INFO] running `Command { std: "docker" "start" "-a" "5101280acc1a53b52c23340eb552962ad38c970b3b9d1888767212d07c614a7a", kill_on_drop: false }`
[INFO] [stderr]    Compiling stperf v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/measurement.rs:227:17
[INFO] [stdout]     |
[INFO] [stdout] 227 |             let mut child_lock = child.get_mut();
[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 0.73s
[INFO] running `Command { std: "docker" "inspect" "5101280acc1a53b52c23340eb552962ad38c970b3b9d1888767212d07c614a7a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5101280acc1a53b52c23340eb552962ad38c970b3b9d1888767212d07c614a7a", kill_on_drop: false }`
[INFO] [stdout] 5101280acc1a53b52c23340eb552962ad38c970b3b9d1888767212d07c614a7a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 29cccc1f7d35098aa9ac2d8f98251b04f48c67cc3f509963c8f45d39cf08f672
[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" "29cccc1f7d35098aa9ac2d8f98251b04f48c67cc3f509963c8f45d39cf08f672", 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] [stderr]    Compiling stperf v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/measurement.rs:227:17
[INFO] [stdout]     |
[INFO] [stdout] 227 |             let mut child_lock = child.get_mut();
[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/measurement.rs:227:17
[INFO] [stdout]     |
[INFO] [stdout] 227 |             let mut child_lock = child.get_mut();
[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 test [unoptimized + debuginfo] target(s) in 0.88s
[INFO] running `Command { std: "docker" "inspect" "29cccc1f7d35098aa9ac2d8f98251b04f48c67cc3f509963c8f45d39cf08f672", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "29cccc1f7d35098aa9ac2d8f98251b04f48c67cc3f509963c8f45d39cf08f672", kill_on_drop: false }`
[INFO] [stdout] 29cccc1f7d35098aa9ac2d8f98251b04f48c67cc3f509963c8f45d39cf08f672
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] a6e05268bbf16f350682bbf4ee3fe5102ff74a4d644ab4243462a72fa5a6db48
[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" "a6e05268bbf16f350682bbf4ee3fe5102ff74a4d644ab4243462a72fa5a6db48", kill_on_drop: false }`
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/measurement.rs:227:17
[INFO] [stderr]     |
[INFO] [stderr] 227 |             let mut child_lock = child.get_mut();
[INFO] [stderr]     |                 ----^^^^^^^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/measurement.rs:227:17
[INFO] [stderr]     |
[INFO] [stderr] 227 |             let mut child_lock = child.get_mut();
[INFO] [stderr]     |                 ----^^^^^^^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/stperf-e42dd81d407dd5e4
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests stperf
[INFO] [stdout] 
[INFO] [stdout] running 3 tests
[INFO] [stdout] test src/lib.rs - (line 18) ... ok
[INFO] [stdout] test src/lib.rs - (line 37) ... ok
[INFO] [stdout] test src/lib.rs - (line 121) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 3 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 1.02s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "a6e05268bbf16f350682bbf4ee3fe5102ff74a4d644ab4243462a72fa5a6db48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a6e05268bbf16f350682bbf4ee3fe5102ff74a4d644ab4243462a72fa5a6db48", kill_on_drop: false }`
[INFO] [stdout] a6e05268bbf16f350682bbf4ee3fe5102ff74a4d644ab4243462a72fa5a6db48