[INFO] cloning repository https://github.com/zhangsoledad/tokio-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/zhangsoledad/tokio-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangsoledad%2Ftokio-playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangsoledad%2Ftokio-playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 40cc5ce61b1245020ae8e27a45ce0e57ab55e1cd
[INFO] checking zhangsoledad/tokio-playground against master#36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923 for pr-81863
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangsoledad%2Ftokio-playground" "/workspace/builds/worker-5/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/zhangsoledad/tokio-playground on toolchain 36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/zhangsoledad/tokio-playground
[INFO] finished tweaking git repo https://github.com/zhangsoledad/tokio-playground
[INFO] tweaked toml for git repo https://github.com/zhangsoledad/tokio-playground written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/zhangsoledad/tokio-playground already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1b62a53e27dc62f3d9ce9450ea591e234d42f9a86b40cec3643034347d62a1f6
[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" "1b62a53e27dc62f3d9ce9450ea591e234d42f9a86b40cec3643034347d62a1f6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1b62a53e27dc62f3d9ce9450ea591e234d42f9a86b40cec3643034347d62a1f6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1b62a53e27dc62f3d9ce9450ea591e234d42f9a86b40cec3643034347d62a1f6", kill_on_drop: false }`
[INFO] [stdout] 1b62a53e27dc62f3d9ce9450ea591e234d42f9a86b40cec3643034347d62a1f6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 994673f6a4a356a725432956985075dfd0119f8101b0699096fccaa4ede36466
[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" "994673f6a4a356a725432956985075dfd0119f8101b0699096fccaa4ede36466", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.70
[INFO] [stderr]    Compiling proc-macro2 v1.0.13
[INFO] [stderr]    Compiling syn v1.0.22
[INFO] [stderr]     Checking arc-swap v0.4.6
[INFO] [stderr]     Checking pin-project-lite v0.1.5
[INFO] [stderr]     Checking futures-core v0.3.5
[INFO] [stderr]    Compiling quote v1.0.6
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking net2 v0.2.34
[INFO] [stderr]     Checking signal-hook-registry v1.2.0
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking mio v0.6.22
[INFO] [stderr]     Checking mio-uds v0.6.8
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]     Checking tokio v0.2.21
[INFO] [stderr]     Checking tokio-playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/blocking.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |             t.await;
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/block_in_place.rs:28:13
[INFO] [stdout]    |
[INFO] [stdout] 28 |             t.await;
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/spawn_blocking.rs:29:13
[INFO] [stdout]    |
[INFO] [stdout] 29 |             t.await;
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 33.33s
[INFO] running `Command { std: "docker" "inspect" "994673f6a4a356a725432956985075dfd0119f8101b0699096fccaa4ede36466", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "994673f6a4a356a725432956985075dfd0119f8101b0699096fccaa4ede36466", kill_on_drop: false }`
[INFO] [stdout] 994673f6a4a356a725432956985075dfd0119f8101b0699096fccaa4ede36466