[INFO] fetching crate sonos_discovery 0.0.2...
[INFO] checking sonos_discovery-0.0.2 against master#7f5a42b073dc2bee2aa625052eb066ee07072048 for pr-78991
[INFO] extracting crate sonos_discovery 0.0.2 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate sonos_discovery 0.0.2 on toolchain 7f5a42b073dc2bee2aa625052eb066ee07072048
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7f5a42b073dc2bee2aa625052eb066ee07072048" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate sonos_discovery 0.0.2
[INFO] finished tweaking crates.io crate sonos_discovery 0.0.2
[INFO] tweaked toml for crates.io crate sonos_discovery 0.0.2 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate sonos_discovery 0.0.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7f5a42b073dc2bee2aa625052eb066ee07072048" "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" "+7f5a42b073dc2bee2aa625052eb066ee07072048" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a684b60e65060bb291bd7ed9f157c6ff0698b10c5e6738adcb68f518fb7bb24a
[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" "a684b60e65060bb291bd7ed9f157c6ff0698b10c5e6738adcb68f518fb7bb24a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a684b60e65060bb291bd7ed9f157c6ff0698b10c5e6738adcb68f518fb7bb24a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a684b60e65060bb291bd7ed9f157c6ff0698b10c5e6738adcb68f518fb7bb24a", kill_on_drop: false }`
[INFO] [stdout] a684b60e65060bb291bd7ed9f157c6ff0698b10c5e6738adcb68f518fb7bb24a
[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" "+7f5a42b073dc2bee2aa625052eb066ee07072048" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b054e17c7deaa81f08c2a147a6b7528ed0b445442b4f677fb97a097ce64ff4f8
[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" "b054e17c7deaa81f08c2a147a6b7528ed0b445442b4f677fb97a097ce64ff4f8", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.65
[INFO] [stderr]    Compiling num-traits v0.2.9
[INFO] [stderr]    Compiling num-integer v0.1.41
[INFO] [stderr]    Compiling num-bigint v0.2.3
[INFO] [stderr]    Compiling num-complex v0.2.3
[INFO] [stderr]    Compiling num-rational v0.2.2
[INFO] [stderr]    Compiling num-iter v0.1.39
[INFO] [stderr]     Checking num v0.2.0
[INFO] [stderr]     Checking socket v0.0.7
[INFO] [stderr]     Checking sonos_discovery v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stdout]    --> src/lib.rs:122:25
[INFO] [stdout]     |
[INFO] [stdout] 122 |                         sender.send((_addr, _data)).is_ok();
[INFO] [stdout]     |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stdout]    --> src/lib.rs:122:25
[INFO] [stdout]     |
[INFO] [stdout] 122 |                         sender.send((_addr, _data)).is_ok();
[INFO] [stdout]     |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 8.76s
[INFO] running `Command { std: "docker" "inspect" "b054e17c7deaa81f08c2a147a6b7528ed0b445442b4f677fb97a097ce64ff4f8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b054e17c7deaa81f08c2a147a6b7528ed0b445442b4f677fb97a097ce64ff4f8", kill_on_drop: false }`
[INFO] [stdout] b054e17c7deaa81f08c2a147a6b7528ed0b445442b4f677fb97a097ce64ff4f8