[INFO] fetching crate completable_future 0.1.0...
[INFO] checking completable_future-0.1.0 against try#6f12b8fe67b4eed2e838dab803ed9493b9d62c0f for pr-79073
[INFO] extracting crate completable_future 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate completable_future 0.1.0 on toolchain 6f12b8fe67b4eed2e838dab803ed9493b9d62c0f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f12b8fe67b4eed2e838dab803ed9493b9d62c0f" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate completable_future 0.1.0
[INFO] finished tweaking crates.io crate completable_future 0.1.0
[INFO] tweaked toml for crates.io crate completable_future 0.1.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f12b8fe67b4eed2e838dab803ed9493b9d62c0f" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f12b8fe67b4eed2e838dab803ed9493b9d62c0f" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+6f12b8fe67b4eed2e838dab803ed9493b9d62c0f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] aa7c7bcf804f82ee03adec0f4bcdc84fff3b56460dce1278c098a17e95f459ba
[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" "aa7c7bcf804f82ee03adec0f4bcdc84fff3b56460dce1278c098a17e95f459ba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "aa7c7bcf804f82ee03adec0f4bcdc84fff3b56460dce1278c098a17e95f459ba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aa7c7bcf804f82ee03adec0f4bcdc84fff3b56460dce1278c098a17e95f459ba", kill_on_drop: false }`
[INFO] [stdout] aa7c7bcf804f82ee03adec0f4bcdc84fff3b56460dce1278c098a17e95f459ba
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+6f12b8fe67b4eed2e838dab803ed9493b9d62c0f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2b2696aa231461deed6e83529ee98f5ef756f2aa078b2565c95f60ae905302a5
[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" "2b2696aa231461deed6e83529ee98f5ef756f2aa078b2565c95f60ae905302a5", kill_on_drop: false }`
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]     Checking fnv v1.0.7
[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]     Checking completable_future v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking log v0.4.11
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking net2 v0.2.35
[INFO] [stderr]     Checking lock_api v0.3.4
[INFO] [stderr]     Checking tokio-sync v0.1.8
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/lib.rs:77:17
[INFO] [stdout]    |
[INFO] [stdout] 77 |                 mem::replace(self, WakerWrapper::Registered(waker));
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking mio v0.6.22
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]     Checking smallvec v0.6.13
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]     Checking tokio-io v0.1.13
[INFO] [stderr]     Checking tokio-executor v0.1.10
[INFO] [stderr]     Checking crossbeam-queue v0.2.3
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]     Checking mio-uds v0.6.8
[INFO] [stderr]     Checking tokio-timer v0.2.13
[INFO] [stderr]     Checking tokio-current-thread v0.1.7
[INFO] [stderr]     Checking tokio-codec v0.1.2
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]     Checking tokio-threadpool v0.1.18
[INFO] [stderr]     Checking tokio-reactor v0.1.12
[INFO] [stderr]     Checking tokio-fs v0.1.7
[INFO] [stderr]     Checking tokio-tcp v0.1.4
[INFO] [stderr]     Checking tokio-uds v0.2.7
[INFO] [stderr]     Checking tokio-udp v0.1.6
[INFO] [stderr]     Checking tokio v0.1.22
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/lib.rs:77:17
[INFO] [stdout]    |
[INFO] [stdout] 77 |                 mem::replace(self, WakerWrapper::Registered(waker));
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> tests/tests.rs:75:7
[INFO] [stdout]    |
[INFO] [stdout] 75 |         let mut tm = mutate_counter.clone();
[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]   --> tests/tests.rs:97:7
[INFO] [stdout]    |
[INFO] [stdout] 97 |         let mut tm = mutate_counter.clone();
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 15.30s
[INFO] running `Command { std: "docker" "inspect" "2b2696aa231461deed6e83529ee98f5ef756f2aa078b2565c95f60ae905302a5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2b2696aa231461deed6e83529ee98f5ef756f2aa078b2565c95f60ae905302a5", kill_on_drop: false }`
[INFO] [stdout] 2b2696aa231461deed6e83529ee98f5ef756f2aa078b2565c95f60ae905302a5