[INFO] fetching crate bve 0.0.1...
[INFO] documenting bve-0.0.1 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate bve 0.0.1 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate bve 0.0.1 on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate bve 0.0.1
[INFO] finished tweaking crates.io crate bve 0.0.1
[INFO] tweaked toml for crates.io crate bve 0.0.1 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6bed3c2d610846fc56401402f4e64a44265ab14c6cd01856dac27f16aaa8c6ce
[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" "6bed3c2d610846fc56401402f4e64a44265ab14c6cd01856dac27f16aaa8c6ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6bed3c2d610846fc56401402f4e64a44265ab14c6cd01856dac27f16aaa8c6ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6bed3c2d610846fc56401402f4e64a44265ab14c6cd01856dac27f16aaa8c6ce", kill_on_drop: false }`
[INFO] [stdout] 6bed3c2d610846fc56401402f4e64a44265ab14c6cd01856dac27f16aaa8c6ce
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "RUSTDOCFLAGS=--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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--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] af05432f817781a1933fb730bc59ed1ebbdbb73752e4126fc6d93a56c1cf9aa5
[INFO] running `Command { std: "docker" "start" "-a" "af05432f817781a1933fb730bc59ed1ebbdbb73752e4126fc6d93a56c1cf9aa5", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.39
[INFO] [stderr]     Checking tinystr v0.3.4
[INFO] [stderr]    Compiling adler v0.2.3
[INFO] [stderr]    Compiling gimli v0.22.0
[INFO] [stderr]    Compiling rustc-demangle v0.1.16
[INFO] [stderr]    Compiling object v0.20.0
[INFO] [stderr]     Checking stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling lexical-core v0.7.4
[INFO] [stderr]    Compiling cgmath v0.17.0
[INFO] [stderr]     Checking arrayvec v0.5.1
[INFO] [stderr]     Checking fluent-syntax v0.9.3
[INFO] [stderr]    Compiling either v1.6.0
[INFO] [stderr]     Checking static_assertions v1.1.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]     Checking tracing-core v0.1.15
[INFO] [stderr]    Compiling nom v5.1.2
[INFO] [stderr]    Compiling miniz_oxide v0.4.1
[INFO] [stderr]     Checking itertools v0.8.2
[INFO] [stderr]    Compiling unic-langid-impl v0.8.0
[INFO] [stderr]     Checking csv-core v0.1.10
[INFO] [stderr]     Checking fxhash v0.2.1
[INFO] [stderr]     Checking regex-automata v0.1.9
[INFO] [stderr]     Checking chardetng v0.1.9
[INFO] [stderr]     Checking unic-locale-impl v0.8.0
[INFO] [stderr]     Checking locale_config v0.3.0
[INFO] [stderr]     Checking type-map v0.3.0
[INFO] [stderr]     Checking unic-locale v0.8.0
[INFO] [stderr]     Checking crossbeam-channel v0.4.3
[INFO] [stderr]     Checking crossbeam-queue v0.2.3
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]     Checking crossbeam v0.7.3
[INFO] [stderr]    Compiling addr2line v0.13.0
[INFO] [stderr]    Compiling backtrace v0.3.50
[INFO] [stderr]    Compiling synstructure v0.12.4
[INFO] [stderr]    Compiling darling_core v0.10.2
[INFO] [stderr]    Compiling serde_derive v1.0.115
[INFO] [stderr]    Compiling unic-langid-macros-impl v0.8.0
[INFO] [stderr]    Compiling rental-impl v0.5.5
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling tracing-attributes v0.1.11
[INFO] [stderr]    Compiling darling_macro v0.10.2
[INFO] [stderr]     Checking unic-langid-macros v0.8.0
[INFO] [stderr]     Checking unic-langid v0.8.0
[INFO] [stderr]     Checking intl_pluralrules v6.0.0
[INFO] [stderr]     Checking fluent-langneg v0.12.1
[INFO] [stderr]     Checking intl-memoizer v0.3.0
[INFO] [stderr]    Compiling failure v0.1.8
[INFO] [stderr]    Compiling include_dir_impl v0.5.0
[INFO] [stderr]     Checking tracing v0.1.19
[INFO] [stderr]    Compiling darling v0.10.2
[INFO] [stderr]    Compiling bve-derive v0.0.1
[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/bve-derive-0.0.1/src/lib.rs:50:1
[INFO] [stdout]    |
[INFO] [stdout] 50 | #![feature(core_panic)]
[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 `bve-derive`.
[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" "af05432f817781a1933fb730bc59ed1ebbdbb73752e4126fc6d93a56c1cf9aa5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "af05432f817781a1933fb730bc59ed1ebbdbb73752e4126fc6d93a56c1cf9aa5", kill_on_drop: false }`
[INFO] [stdout] af05432f817781a1933fb730bc59ed1ebbdbb73752e4126fc6d93a56c1cf9aa5