[INFO] cloning repository https://github.com/ajh/future_playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ajh/future_playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fajh%2Ffuture_playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fajh%2Ffuture_playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6dd157375a41e586f071ff630bc6f566e422a76a
[INFO] checking ajh/future_playground against try#d990716b6a1fdde1300748828a9c9e79dfd0b898 for pr-74846
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fajh%2Ffuture_playground" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ajh/future_playground on toolchain d990716b6a1fdde1300748828a9c9e79dfd0b898
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/ajh/future_playground
[INFO] finished tweaking git repo https://github.com/ajh/future_playground
[INFO] tweaked toml for git repo https://github.com/ajh/future_playground written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/ajh/future_playground already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded futures-cpupool v0.1.2
[INFO] [stderr]   Downloaded nix v0.7.0
[INFO] [stderr]   Downloaded mio v0.6.1
[INFO] [stderr]   Downloaded futures v0.1.6
[INFO] [stderr]   Downloaded tokio-core v0.1.1
[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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 54063b0f460ae6d006f92a8949c9d71d4ad07798db73c3f87e1c7cdc909713f1
[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" "54063b0f460ae6d006f92a8949c9d71d4ad07798db73c3f87e1c7cdc909713f1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "54063b0f460ae6d006f92a8949c9d71d4ad07798db73c3f87e1c7cdc909713f1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "54063b0f460ae6d006f92a8949c9d71d4ad07798db73c3f87e1c7cdc909713f1", kill_on_drop: false }`
[INFO] [stdout] 54063b0f460ae6d006f92a8949c9d71d4ad07798db73c3f87e1c7cdc909713f1
[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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ae12f911fd988711abcd58aa8e54a4ca1298630b30cdf4fc5181cbdc6aecc3bb
[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" "ae12f911fd988711abcd58aa8e54a4ca1298630b30cdf4fc5181cbdc6aecc3bb", kill_on_drop: false }`
[INFO] [stderr]    Compiling semver v0.1.20
[INFO] [stderr]     Checking libc v0.2.18
[INFO] [stderr]     Checking log v0.3.6
[INFO] [stderr]     Checking cfg-if v0.1.0
[INFO] [stderr]     Checking bitflags v0.4.0
[INFO] [stderr]     Checking lazycell v0.4.0
[INFO] [stderr]     Checking slab v0.3.0
[INFO] [stderr]     Checking scoped-tls v0.1.0
[INFO] [stderr]     Checking crossbeam v0.2.10
[INFO] [stderr]     Checking futures v0.1.6
[INFO] [stderr]     Checking net2 v0.2.26
[INFO] [stderr]     Checking num_cpus v1.2.0
[INFO] [stderr]    Compiling rustc_version v0.1.7
[INFO] [stderr]    Compiling nix v0.7.0
[INFO] [stderr]     Checking futures-cpupool v0.1.2
[INFO] [stderr]     Checking mio v0.6.1
[INFO] [stderr]     Checking tokio-core v0.1.1
[INFO] [stderr]     Checking tokiproto v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 8.25s
[INFO] running `Command { std: "docker" "inspect" "ae12f911fd988711abcd58aa8e54a4ca1298630b30cdf4fc5181cbdc6aecc3bb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ae12f911fd988711abcd58aa8e54a4ca1298630b30cdf4fc5181cbdc6aecc3bb", kill_on_drop: false }`
[INFO] [stdout] ae12f911fd988711abcd58aa8e54a4ca1298630b30cdf4fc5181cbdc6aecc3bb