[INFO] fetching crate stperf 0.1.4...
[INFO] testing stperf-0.1.4 against 1.49.0 for beta-1.50-1
[INFO] extracting crate stperf 0.1.4 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate stperf 0.1.4 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "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-3/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+1.49.0" "metadata" "--no-deps" "--format-version=1", 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] 3d58a4ccfcab365965c6858ff872ed90eb726c17caa01aaf8baeeac0edfaa0ce
[INFO] running `Command { std: "docker" "start" "-a" "3d58a4ccfcab365965c6858ff872ed90eb726c17caa01aaf8baeeac0edfaa0ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3d58a4ccfcab365965c6858ff872ed90eb726c17caa01aaf8baeeac0edfaa0ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3d58a4ccfcab365965c6858ff872ed90eb726c17caa01aaf8baeeac0edfaa0ce", kill_on_drop: false }`
[INFO] [stdout] 3d58a4ccfcab365965c6858ff872ed90eb726c17caa01aaf8baeeac0edfaa0ce
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8754909bf801a969b039f358b0184b9e2360896c15b6f55def5d4648294ee976
[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" "8754909bf801a969b039f358b0184b9e2360896c15b6f55def5d4648294ee976", 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] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.62s
[INFO] running `Command { std: "docker" "inspect" "8754909bf801a969b039f358b0184b9e2360896c15b6f55def5d4648294ee976", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8754909bf801a969b039f358b0184b9e2360896c15b6f55def5d4648294ee976", kill_on_drop: false }`
[INFO] [stdout] 8754909bf801a969b039f358b0184b9e2360896c15b6f55def5d4648294ee976
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+1.49.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 082b6436ca5989c6b65b4bd7f5ca3d5f654366004aed77c7e200d120b351597d
[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" "082b6436ca5989c6b65b4bd7f5ca3d5f654366004aed77c7e200d120b351597d", kill_on_drop: false }`
[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 0.60s
[INFO] running `Command { std: "docker" "inspect" "082b6436ca5989c6b65b4bd7f5ca3d5f654366004aed77c7e200d120b351597d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "082b6436ca5989c6b65b4bd7f5ca3d5f654366004aed77c7e200d120b351597d", kill_on_drop: false }`
[INFO] [stdout] 082b6436ca5989c6b65b4bd7f5ca3d5f654366004aed77c7e200d120b351597d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+1.49.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 11b863ef781493ccba93e624cdcb09b1c1122ed3e83aa985c672f570d15d0368
[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" "11b863ef781493ccba93e624cdcb09b1c1122ed3e83aa985c672f570d15d0368", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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 1.14s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/stperf-6566ab7396fdcf17
[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
[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
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "11b863ef781493ccba93e624cdcb09b1c1122ed3e83aa985c672f570d15d0368", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "11b863ef781493ccba93e624cdcb09b1c1122ed3e83aa985c672f570d15d0368", kill_on_drop: false }`
[INFO] [stdout] 11b863ef781493ccba93e624cdcb09b1c1122ed3e83aa985c672f570d15d0368