[INFO] crate ak 0.1.1 is already in cache
[INFO] checking ak-0.1.1 against try#5e633973aa9255a88b65a39484627bb54e6044b3 for pr-66063
[INFO] extracting crate ak 0.1.1 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate ak 0.1.1 on toolchain 5e633973aa9255a88b65a39484627bb54e6044b3
[INFO] running `"/workspace/cargo-home/bin/cargo" "+5e633973aa9255a88b65a39484627bb54e6044b3" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate ak 0.1.1
[INFO] finished tweaking crates.io crate ak 0.1.1
[INFO] tweaked toml for crates.io crate ak 0.1.1 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate ak 0.1.1 already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+5e633973aa9255a88b65a39484627bb54e6044b3" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=allow" "-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" "+5e633973aa9255a88b65a39484627bb54e6044b3" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] d12b67326a1f60a819279429c279a2fcd11cb81062cf5451665744642778e6c4
[INFO] running `"docker" "start" "-a" "d12b67326a1f60a819279429c279a2fcd11cb81062cf5451665744642778e6c4"`
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling proc-macro-nested v0.1.3
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking ak-rt v0.1.0
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking num_cpus v1.10.1
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling proc-macro-hack v0.5.10
[INFO] [stderr]    Compiling ak-codegen v0.1.0
[INFO] [stderr]    Compiling async-trait v0.1.13
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/ak-codegen-0.1.0/src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(box_syntax)]
[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: could not compile `ak-codegen`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "d12b67326a1f60a819279429c279a2fcd11cb81062cf5451665744642778e6c4"`
[INFO] running `"docker" "rm" "-f" "d12b67326a1f60a819279429c279a2fcd11cb81062cf5451665744642778e6c4"`
[INFO] [stdout] d12b67326a1f60a819279429c279a2fcd11cb81062cf5451665744642778e6c4