[INFO] cloning repository https://github.com/manifest/mqtt-service-example-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/manifest/mqtt-service-example-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmanifest%2Fmqtt-service-example-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmanifest%2Fmqtt-service-example-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8eecea2efe7e6a94cd7f3fbfd861ad63d9a6599e
[INFO] testing manifest/mqtt-service-example-rs against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmanifest%2Fmqtt-service-example-rs" "/workspace/builds/worker-14/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-14/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/manifest/mqtt-service-example-rs 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 git repo https://github.com/manifest/mqtt-service-example-rs
[INFO] finished tweaking git repo https://github.com/manifest/mqtt-service-example-rs
[INFO] tweaked toml for git repo https://github.com/manifest/mqtt-service-example-rs written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate git repo https://github.com/manifest/mqtt-service-example-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "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-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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] [stdout] 3a8479f1e6bde1acf756fede99d651ee04b644315046a515133adf2d721d98d2
[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" "3a8479f1e6bde1acf756fede99d651ee04b644315046a515133adf2d721d98d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3a8479f1e6bde1acf756fede99d651ee04b644315046a515133adf2d721d98d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3a8479f1e6bde1acf756fede99d651ee04b644315046a515133adf2d721d98d2", kill_on_drop: false }`
[INFO] [stdout] 3a8479f1e6bde1acf756fede99d651ee04b644315046a515133adf2d721d98d2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] e9e6636ec1a668837d930263f4fe8dea7d8bb63166b4bf849dbe4d3fcc1dc853
[INFO] running `Command { std: "docker" "start" "-a" "e9e6636ec1a668837d930263f4fe8dea7d8bb63166b4bf849dbe4d3fcc1dc853", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v0.15.33
[INFO] [stderr]    Compiling either v1.5.2
[INFO] [stderr]    Compiling rust-ini v0.13.0
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling ring v0.13.5
[INFO] [stderr]    Compiling serde_test v0.8.23
[INFO] [stderr]    Compiling iovec v0.1.2
[INFO] [stderr]    Compiling num_cpus v1.10.0
[INFO] [stderr]    Compiling net2 v0.2.33
[INFO] [stderr]    Compiling atty v0.2.11
[INFO] [stderr]    Compiling time v0.1.42
[INFO] [stderr]    Compiling num-integer v0.1.39
[INFO] [stderr]    Compiling toml v0.4.10
[INFO] [stderr]    Compiling backtrace-sys v0.1.28
[INFO] [stderr]    Compiling serde_json v1.0.39
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling env_logger v0.5.13
[INFO] [stderr]    Compiling env_logger v0.6.1
[INFO] [stderr]    Compiling backtrace v0.3.15
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.14
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling mio v0.6.16
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/futures-core-preview-0.3.0-alpha.14/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(futures_api)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `futures-core-preview`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "e9e6636ec1a668837d930263f4fe8dea7d8bb63166b4bf849dbe4d3fcc1dc853", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e9e6636ec1a668837d930263f4fe8dea7d8bb63166b4bf849dbe4d3fcc1dc853", kill_on_drop: false }`
[INFO] [stdout] e9e6636ec1a668837d930263f4fe8dea7d8bb63166b4bf849dbe4d3fcc1dc853