[INFO] updating cached repository https://github.com/ibaryshnikov/runtime-tcp-chat
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] f5ee8116139ee489647b4c524201dc49d8309ccd
[INFO] testing ibaryshnikov/runtime-tcp-chat against 1.38.0 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fibaryshnikov%2Fruntime-tcp-chat" "work/builds/worker-5/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ibaryshnikov/runtime-tcp-chat on toolchain 1.38.0
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/ibaryshnikov/runtime-tcp-chat
[INFO] finished tweaking git repo https://github.com/ibaryshnikov/runtime-tcp-chat
[INFO] tweaked toml for git repo https://github.com/ibaryshnikov/runtime-tcp-chat written to work/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/ibaryshnikov/runtime-tcp-chat already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-5/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "build" "--frozen"`
[INFO] [stdout] 2bc0c3e1323ce6fb6c17a0a97c4e87fc6b3c2a348bfab0ffd02b2065e6115459
[INFO] running `"docker" "start" "-a" "2bc0c3e1323ce6fb6c17a0a97c4e87fc6b3c2a348bfab0ffd02b2065e6115459"`
[INFO] [stderr]    Compiling syn v0.15.34
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.16
[INFO] [stderr]    Compiling proc-macro-nested v0.1.3
[INFO] [stderr]    Compiling async-ready v2.1.0
[INFO] [stderr]    Compiling async-datagram v2.2.0
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling quote v0.6.12
[INFO] [stderr]    Compiling net2 v0.2.33
[INFO] [stderr]    Compiling iovec v0.1.2
[INFO] [stderr]    Compiling num_cpus v1.10.0
[INFO] [stderr]    Compiling crossbeam-deque v0.6.3
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/async-ready-2.1.0/src/lib.rs:42:1
[INFO] [stderr]    |
[INFO] [stderr] 42 | #![feature(futures_api)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/async-datagram-2.2.0/src/lib.rs:43:1
[INFO] [stderr]    |
[INFO] [stderr] 43 | #![feature(futures_api)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: Could not compile `async-ready`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `async-datagram`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "2bc0c3e1323ce6fb6c17a0a97c4e87fc6b3c2a348bfab0ffd02b2065e6115459"`
[INFO] running `"docker" "rm" "-f" "2bc0c3e1323ce6fb6c17a0a97c4e87fc6b3c2a348bfab0ffd02b2065e6115459"`
[INFO] [stdout] 2bc0c3e1323ce6fb6c17a0a97c4e87fc6b3c2a348bfab0ffd02b2065e6115459