[INFO] cloning repository https://github.com/TheJakeSchmidt/wikipedia-minus-wikipedians
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/TheJakeSchmidt/wikipedia-minus-wikipedians" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTheJakeSchmidt%2Fwikipedia-minus-wikipedians", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTheJakeSchmidt%2Fwikipedia-minus-wikipedians'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 60410fa53241a78411821b7d76fb9ba9488043bf
[INFO] testing TheJakeSchmidt/wikipedia-minus-wikipedians against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTheJakeSchmidt%2Fwikipedia-minus-wikipedians" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/TheJakeSchmidt/wikipedia-minus-wikipedians on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/TheJakeSchmidt/wikipedia-minus-wikipedians
[INFO] finished tweaking git repo https://github.com/TheJakeSchmidt/wikipedia-minus-wikipedians
[INFO] tweaked toml for git repo https://github.com/TheJakeSchmidt/wikipedia-minus-wikipedians written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/TheJakeSchmidt/wikipedia-minus-wikipedians already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr] error: the lock file /workspace/builds/worker-2/source/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] [stderr] If you want to try to generate the lock file without accessing the network, use the --offline flag.
[INFO] the lockfile is outdated, regenerating it
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 47f1bc447a5dc76464bff3de4f19a5cdfa41ef5b0630e32a2981b73529dd219f
[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" "47f1bc447a5dc76464bff3de4f19a5cdfa41ef5b0630e32a2981b73529dd219f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "47f1bc447a5dc76464bff3de4f19a5cdfa41ef5b0630e32a2981b73529dd219f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "47f1bc447a5dc76464bff3de4f19a5cdfa41ef5b0630e32a2981b73529dd219f", kill_on_drop: false }`
[INFO] [stdout] 47f1bc447a5dc76464bff3de4f19a5cdfa41ef5b0630e32a2981b73529dd219f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4d3bd8a83ed7429009706da1fc2ad34caf472d4eaf0f9f520a440402fff9e73d
[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" "4d3bd8a83ed7429009706da1fc2ad34caf472d4eaf0f9f520a440402fff9e73d", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.58
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]    Compiling siphasher v0.3.3
[INFO] [stderr]    Compiling encoding_index_tests v0.1.4
[INFO] [stderr]    Compiling new_debug_unreachable v1.0.4
[INFO] [stderr]    Compiling mac v0.1.1
[INFO] [stderr]    Compiling bytes v1.0.0
[INFO] [stderr]    Compiling precomputed-hash v0.1.1
[INFO] [stderr]    Compiling utf-8 v0.7.5
[INFO] [stderr]    Compiling anyhow v1.0.37
[INFO] [stderr]    Compiling futures-core v0.3.8
[INFO] [stderr]    Compiling serde v0.8.23
[INFO] [stderr]    Compiling ucd-util v0.1.8
[INFO] [stderr]    Compiling regex v0.2.11
[INFO] [stderr]    Compiling utf8-ranges v1.0.4
[INFO] [stderr]    Compiling futures-task v0.3.8
[INFO] [stderr]    Compiling rc v0.1.1
[INFO] [stderr]    Compiling arc-swap v0.4.8
[INFO] [stderr]    Compiling log-mdc v0.1.0
[INFO] [stderr]    Compiling sha1 v0.6.0
[INFO] [stderr]    Compiling regex-syntax v0.4.2
[INFO] [stderr]    Compiling uuid v0.8.1
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.3.1
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-rational v0.3.2
[INFO] [stderr]    Compiling tokio v1.0.1
[INFO] [stderr]    Compiling thread_local v0.3.6
[INFO] [stderr]    Compiling proc-macro-hack v0.5.19
[INFO] [stderr]    Compiling unreachable v0.1.1
[INFO] [stderr]    Compiling yaml-rust v0.4.5
[INFO] [stderr]    Compiling futf v0.1.4
[INFO] [stderr]    Compiling encoding-index-korean v1.20141219.5
[INFO] [stderr]    Compiling encoding-index-tradchinese v1.20141219.5
[INFO] [stderr]    Compiling encoding-index-simpchinese v1.20141219.5
[INFO] [stderr]    Compiling encoding-index-singlebyte v1.20141219.5
[INFO] [stderr]    Compiling encoding-index-japanese v1.20141219.5
[INFO] [stderr]    Compiling regex-syntax v0.5.6
[INFO] [stderr]    Compiling phf_shared v0.8.0
[INFO] [stderr]    Compiling futures-channel v0.3.8
[INFO] [stderr]    Compiling standback v0.2.14
[INFO] [stderr]    Compiling time v0.2.23
[INFO] [stderr]    Compiling tracing v0.1.22
[INFO] [stderr]    Compiling http-body v0.4.0
[INFO] [stderr]    Compiling debug_unreachable v0.1.1
[INFO] [stderr]    Compiling parking_lot_core v0.8.2
[INFO] [stderr]    Compiling thread-id v3.3.0
[INFO] [stderr]    Compiling unicase v1.4.2
[INFO] [stderr]    Compiling tendril v0.4.1
[INFO] [stderr]    Compiling phf v0.8.0
[INFO] [stderr]    Compiling aho-corasick v0.6.10
[INFO] [stderr]    Compiling aho-corasick v0.7.15
[INFO] [stderr]    Compiling combine v4.5.1
[INFO] [stderr]    Compiling idna v0.1.5
[INFO] [stderr]    Compiling base64 v0.9.3
[INFO] [stderr]    Compiling plugin v0.2.6
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling encoding v0.2.33
[INFO] [stderr]    Compiling phf_shared v0.7.24
[INFO] [stderr]    Compiling parking_lot v0.11.1
[INFO] [stderr]    Compiling tempfile v1.1.3
[INFO] [stderr]    Compiling rand_pcg v0.2.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling phf_generator v0.7.24
[INFO] [stderr]    Compiling phf v0.7.24
[INFO] [stderr]    Compiling url v1.7.2
[INFO] [stderr]    Compiling regex v1.4.2
[INFO] [stderr]    Compiling tendril v0.1.6
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling phf_codegen v0.7.24
[INFO] [stderr]    Compiling string_cache v0.2.29
[INFO] [stderr]    Compiling ordered-float v2.0.1
[INFO] [stderr]    Compiling num-complex v0.3.1
[INFO] [stderr]    Compiling html5ever v0.2.11
[INFO] [stderr]    Compiling mime_guess v1.8.8
[INFO] [stderr]    Compiling chrono v0.4.19
[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/regex-0.2.11/src/lib.rs:522:34
[INFO] [stdout]     |
[INFO] [stdout] 522 | #![cfg_attr(feature = "pattern", feature(pattern))]
[INFO] [stdout]     |                                  ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling phf_generator v0.8.0
[INFO] [stderr]    Compiling phf_codegen v0.8.0
[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 `regex`
[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" "4d3bd8a83ed7429009706da1fc2ad34caf472d4eaf0f9f520a440402fff9e73d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d3bd8a83ed7429009706da1fc2ad34caf472d4eaf0f9f520a440402fff9e73d", kill_on_drop: false }`
[INFO] [stdout] 4d3bd8a83ed7429009706da1fc2ad34caf472d4eaf0f9f520a440402fff9e73d