[INFO] fetching crate rafka 0.1.0...
[INFO] testing rafka-0.1.0 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate rafka 0.1.0 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate rafka 0.1.0 on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate rafka 0.1.0
[INFO] finished tweaking crates.io crate rafka 0.1.0
[INFO] tweaked toml for crates.io crate rafka 0.1.0 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tower-util v0.3.1
[INFO] [stderr]   Downloaded tower-discover v0.3.0
[INFO] [stderr]   Downloaded tower-buffer v0.3.0
[INFO] [stderr]   Downloaded tower-retry v0.3.0
[INFO] [stderr]   Downloaded tokio-tower v0.4.0
[INFO] [stderr]   Downloaded tower-load v0.3.0
[INFO] [stderr]   Downloaded tower-layer v0.3.0
[INFO] [stderr]   Downloaded tower-timeout v0.3.0
[INFO] [stderr]   Downloaded tower v0.3.1
[INFO] [stderr]   Downloaded tower-limit v0.3.1
[INFO] [stderr]   Downloaded tower-load-shed v0.3.0
[INFO] [stderr]   Downloaded rafka_codegen v0.0.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5cac5f25cdba63506ce2db8b5e9c1820d1661da30c18eac8d29d472714e35f05
[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" "5cac5f25cdba63506ce2db8b5e9c1820d1661da30c18eac8d29d472714e35f05", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5cac5f25cdba63506ce2db8b5e9c1820d1661da30c18eac8d29d472714e35f05", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5cac5f25cdba63506ce2db8b5e9c1820d1661da30c18eac8d29d472714e35f05", kill_on_drop: false }`
[INFO] [stdout] 5cac5f25cdba63506ce2db8b5e9c1820d1661da30c18eac8d29d472714e35f05
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "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] c1f4ef561d897cf3df4d5cd6fa8ed2bc1c3843fbe7acf8268c051184438e9ebc
[INFO] running `Command { std: "docker" "start" "-a" "c1f4ef561d897cf3df4d5cd6fa8ed2bc1c3843fbe7acf8268c051184438e9ebc", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.57
[INFO] [stderr]    Compiling libc v0.2.81
[INFO] [stderr]    Compiling memchr v2.3.4
[INFO] [stderr]    Compiling pin-project-internal v0.4.27
[INFO] [stderr]    Compiling once_cell v1.5.2
[INFO] [stderr]    Compiling pin-project-lite v0.1.11
[INFO] [stderr]    Compiling bytes v0.5.6
[INFO] [stderr]    Compiling tower-service v0.3.0
[INFO] [stderr]    Compiling futures-sink v0.3.8
[INFO] [stderr]    Compiling proc-macro-nested v0.1.6
[INFO] [stderr]    Compiling tower-layer v0.3.0
[INFO] [stderr]    Compiling futures-io v0.3.8
[INFO] [stderr]    Compiling untrusted v0.7.1
[INFO] [stderr]    Compiling base64 v0.12.3
[INFO] [stderr]    Compiling tracing-core v0.1.17
[INFO] [stderr]    Compiling ring v0.16.19
[INFO] [stderr]    Compiling futures-channel v0.3.8
[INFO] [stderr]    Compiling crossbeam-queue v0.2.3
[INFO] [stderr]    Compiling futures-task v0.3.8
[INFO] [stderr]    Compiling crossbeam v0.7.3
[INFO] [stderr]    Compiling net2 v0.2.37
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling signal-hook-registry v1.3.0
[INFO] [stderr]    Compiling mio v0.6.23
[INFO] [stderr]    Compiling mio-uds v0.6.8
[INFO] [stderr]    Compiling webpki v0.21.4
[INFO] [stderr]    Compiling sct v0.6.0
[INFO] [stderr]    Compiling rustls v0.18.1
[INFO] [stderr]    Compiling tokio-macros v0.2.6
[INFO] [stderr]    Compiling pin-project-internal v1.0.2
[INFO] [stderr]    Compiling futures-macro v0.3.8
[INFO] [stderr]    Compiling tracing-attributes v0.1.11
[INFO] [stderr]    Compiling rafka_codegen v0.0.0
[INFO] [stderr]    Compiling tokio v0.2.24
[INFO] [stderr]    Compiling tracing v0.1.22
[INFO] [stderr]    Compiling pin-project v1.0.2
[INFO] [stderr]    Compiling futures-util v0.3.8
[INFO] [stderr]    Compiling pin-project v0.4.27
[INFO] [stderr]    Compiling tower-discover v0.3.0
[INFO] [stderr]    Compiling tower-load-shed v0.3.0
[INFO] [stderr]    Compiling tower-load v0.3.0
[INFO] [stderr]    Compiling tower-buffer v0.3.0
[INFO] [stderr]    Compiling tower-timeout v0.3.0
[INFO] [stderr]    Compiling tower-retry v0.3.0
[INFO] [stderr]    Compiling tokio-util v0.3.1
[INFO] [stderr]    Compiling tokio-rustls v0.14.1
[INFO] [stderr]    Compiling tower-limit v0.3.1
[INFO] [stderr]    Compiling tower-util v0.3.1
[INFO] [stderr]    Compiling futures-executor v0.3.8
[INFO] [stderr]    Compiling tokio-tower v0.4.0
[INFO] [stderr]    Compiling futures v0.3.8
[INFO] [stderr]    Compiling tower v0.3.1
[INFO] [stderr]    Compiling rafka v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(min_const_generics)]
[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 `rafka`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "c1f4ef561d897cf3df4d5cd6fa8ed2bc1c3843fbe7acf8268c051184438e9ebc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c1f4ef561d897cf3df4d5cd6fa8ed2bc1c3843fbe7acf8268c051184438e9ebc", kill_on_drop: false }`
[INFO] [stdout] c1f4ef561d897cf3df4d5cd6fa8ed2bc1c3843fbe7acf8268c051184438e9ebc