[INFO] fetching crate wu-diff 0.1.2...
[INFO] checking wu-diff-0.1.2 against beta for pr-78714
[INFO] extracting crate wu-diff 0.1.2 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate wu-diff 0.1.2 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate wu-diff 0.1.2
[INFO] finished tweaking crates.io crate wu-diff 0.1.2
[INFO] tweaked toml for crates.io crate wu-diff 0.1.2 written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate crates.io crate wu-diff 0.1.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8eb9766417e1f4df2e5d336d649235aad3490d1ec4b10ecfb56b00f6b858107f
[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" "8eb9766417e1f4df2e5d336d649235aad3490d1ec4b10ecfb56b00f6b858107f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8eb9766417e1f4df2e5d336d649235aad3490d1ec4b10ecfb56b00f6b858107f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8eb9766417e1f4df2e5d336d649235aad3490d1ec4b10ecfb56b00f6b858107f", kill_on_drop: false }`
[INFO] [stdout] 8eb9766417e1f4df2e5d336d649235aad3490d1ec4b10ecfb56b00f6b858107f
[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=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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--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] 25f5f3cb8cd995cea95da9d4a81afb0d0615ff9499f86ec5d8f0ed3ae1798246
[INFO] running `Command { std: "docker" "start" "-a" "25f5f3cb8cd995cea95da9d4a81afb0d0615ff9499f86ec5d8f0ed3ae1798246", kill_on_drop: false }`
[INFO] [stderr]     Checking libc v0.2.40
[INFO] [stderr]     Checking cfg-if v0.1.2
[INFO] [stderr]     Checking num-traits v0.2.2
[INFO] [stderr]     Checking lazy_static v1.0.0
[INFO] [stderr]     Checking byteorder v1.2.2
[INFO] [stderr]     Checking either v1.5.0
[INFO] [stderr]    Compiling cc v1.0.10
[INFO] [stderr]    Compiling rayon-core v1.4.0
[INFO] [stderr]    Compiling regex v0.2.10
[INFO] [stderr]     Checking bitflags v1.0.1
[INFO] [stderr]     Checking utf8-ranges v1.0.0
[INFO] [stderr]     Checking serde v1.0.42
[INFO] [stderr]     Checking dtoa v0.4.2
[INFO] [stderr]     Checking unicode-width v0.1.4
[INFO] [stderr]     Checking itoa v0.4.1
[INFO] [stderr]     Checking rustc-demangle v0.1.7
[INFO] [stderr]     Checking strsim v0.7.0
[INFO] [stderr]     Checking quick-error v1.2.1
[INFO] [stderr]     Checking thread-scoped v1.0.2
[INFO] [stderr]     Checking vec_map v0.8.0
[INFO] [stderr]     Checking wu-diff v0.1.2 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling proc-macro2 v0.3.6
[INFO] [stderr]     Checking inflate v0.3.4
[INFO] [stderr]     Checking regex-syntax v0.5.5
[INFO] [stderr]     Checking crossbeam-utils v0.2.2
[INFO] [stderr]     Checking log v0.4.1
[INFO] [stderr]     Checking textwrap v0.9.0
[INFO] [stderr]     Checking gif v0.9.2
[INFO] [stderr]     Checking itertools v0.7.8
[INFO] [stderr]     Checking thread_local v0.3.5
[INFO] [stderr]     Checking deflate v0.7.18
[INFO] [stderr]     Checking term v0.5.1
[INFO] [stderr]     Checking base64 v0.9.2
[INFO] [stderr]    Compiling synstructure v0.6.1
[INFO] [stderr]    Compiling pest_derive v1.0.7
[INFO] [stderr]     Checking crossbeam-epoch v0.3.1
[INFO] [stderr]     Checking num_cpus v1.8.0
[INFO] [stderr]     Checking rand v0.4.2
[INFO] [stderr]     Checking memchr v2.0.1
[INFO] [stderr]     Checking time v0.1.39
[INFO] [stderr]     Checking atty v0.2.9
[INFO] [stderr]     Checking crossbeam-deque v0.2.0
[INFO] [stderr]    Compiling quote v0.5.2
[INFO] [stderr]    Compiling backtrace-sys v0.1.16
[INFO] [stderr]     Checking aho-corasick v0.6.4
[INFO] [stderr]     Checking clap v2.31.2
[INFO] [stderr]     Checking num-integer v0.1.36
[INFO] [stderr]     Checking num-traits v0.1.43
[INFO] [stderr]    Compiling syn v0.13.1
[INFO] [stderr]     Checking itertools-num v0.1.1
[INFO] [stderr]     Checking enum_primitive v0.1.1
[INFO] [stderr]     Checking criterion-plot v0.2.3
[INFO] [stderr]     Checking num-iter v0.1.35
[INFO] [stderr]     Checking chrono v0.4.2
[INFO] [stderr]     Checking num-rational v0.1.42
[INFO] [stderr]    Compiling failure_derive v0.1.1
[INFO] [stderr]     Checking png v0.11.0
[INFO] [stderr]     Checking criterion-stats v0.2.3
[INFO] [stderr]     Checking rayon v1.0.1
[INFO] [stderr]     Checking simplelog v0.5.1
[INFO] [stderr]    Compiling serde_derive_internals v0.23.1
[INFO] [stderr]     Checking jpeg-decoder v0.1.15
[INFO] [stderr]     Checking serde_json v1.0.16
[INFO] [stderr]     Checking image v0.18.0
[INFO] [stderr]    Compiling serde_derive v1.0.42
[INFO] [stderr]     Checking handlebars v0.31.0
[INFO] [stderr]     Checking backtrace v0.3.6
[INFO] [stderr]     Checking failure v0.1.1
[INFO] [stderr]     Checking criterion v0.2.3
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> tests/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(extern_prelude)]
[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 `wu-diff`
[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" "25f5f3cb8cd995cea95da9d4a81afb0d0615ff9499f86ec5d8f0ed3ae1798246", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "25f5f3cb8cd995cea95da9d4a81afb0d0615ff9499f86ec5d8f0ed3ae1798246", kill_on_drop: false }`
[INFO] [stdout] 25f5f3cb8cd995cea95da9d4a81afb0d0615ff9499f86ec5d8f0ed3ae1798246