[INFO] cloning repository https://github.com/djmcgill/de-list-server
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/djmcgill/de-list-server" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjmcgill%2Fde-list-server", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjmcgill%2Fde-list-server'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e2d32b09c0b015f5751e8363c875170be4a6885a
[INFO] documenting djmcgill/de-list-server against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjmcgill%2Fde-list-server" "/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/djmcgill/de-list-server 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 git repo https://github.com/djmcgill/de-list-server
[INFO] finished tweaking git repo https://github.com/djmcgill/de-list-server
[INFO] tweaked toml for git repo https://github.com/djmcgill/de-list-server written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/djmcgill/de-list-server already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", 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] 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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ce325a8f05b0de83d0a1f453e3286fcb64fb280ae3cfd26dd86ec05d161f5315
[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" "ce325a8f05b0de83d0a1f453e3286fcb64fb280ae3cfd26dd86ec05d161f5315", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ce325a8f05b0de83d0a1f453e3286fcb64fb280ae3cfd26dd86ec05d161f5315", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ce325a8f05b0de83d0a1f453e3286fcb64fb280ae3cfd26dd86ec05d161f5315", kill_on_drop: false }`
[INFO] [stdout] ce325a8f05b0de83d0a1f453e3286fcb64fb280ae3cfd26dd86ec05d161f5315
[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" "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] [stdout] ccb65f06f27184dce66bf4716c828a9e5c513829ff5530a783d1b81f536fadf6
[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" "ccb65f06f27184dce66bf4716c828a9e5c513829ff5530a783d1b81f536fadf6", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.51
[INFO] [stderr]    Compiling autocfg v0.1.2
[INFO] [stderr]     Checking cfg-if v0.1.7
[INFO] [stderr]     Checking futures v0.1.26
[INFO] [stderr]    Compiling cc v1.0.34
[INFO] [stderr]    Compiling syn v0.15.30
[INFO] [stderr]    Compiling arrayvec v0.4.10
[INFO] [stderr]    Compiling rand_core v0.4.0
[INFO] [stderr]     Checking either v1.5.2
[INFO] [stderr]    Compiling num-traits v0.2.6
[INFO] [stderr]    Compiling num-integer v0.1.39
[INFO] [stderr]     Checking rustc-demangle v0.1.13
[INFO] [stderr]    Compiling serde v1.0.90
[INFO] [stderr]     Checking string v0.1.3
[INFO] [stderr]    Compiling ucd-trie v0.1.1
[INFO] [stderr]    Compiling slog v2.4.1
[INFO] [stderr]    Compiling openssl v0.10.20
[INFO] [stderr]    Compiling regex v1.1.5
[INFO] [stderr]    Compiling maplit v1.0.1
[INFO] [stderr]     Checking constant_time_eq v0.1.3
[INFO] [stderr]     Checking byte-tools v0.2.0
[INFO] [stderr]     Checking data-encoding v2.1.2
[INFO] [stderr]     Checking opaque-debug v0.2.2
[INFO] [stderr]     Checking fallible-iterator v0.2.0
[INFO] [stderr]     Checking route-recognizer v0.1.12
[INFO] [stderr]     Checking fallible-streaming-iterator v0.1.9
[INFO] [stderr]     Checking tokio-trace-core v0.1.0
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand_jitter v0.1.3
[INFO] [stderr]     Checking owning_ref v0.4.0
[INFO] [stderr]    Compiling unicase v2.3.0
[INFO] [stderr]     Checking log v0.4.6
[INFO] [stderr]     Checking crossbeam-utils v0.6.5
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.14
[INFO] [stderr]    Compiling pest v2.1.0
[INFO] [stderr]     Checking block-padding v0.1.3
[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/futures-core-preview-0.3.0-alpha.14/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(futures_api)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking lru-cache v0.1.2
[INFO] [stderr]     Checking block-buffer v0.3.3
[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 `futures-core-preview`.
[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" "ccb65f06f27184dce66bf4716c828a9e5c513829ff5530a783d1b81f536fadf6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ccb65f06f27184dce66bf4716c828a9e5c513829ff5530a783d1b81f536fadf6", kill_on_drop: false }`
[INFO] [stdout] ccb65f06f27184dce66bf4716c828a9e5c513829ff5530a783d1b81f536fadf6