[INFO] cloning repository https://github.com/lobisquit/paperwok
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/lobisquit/paperwok" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flobisquit%2Fpaperwok", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flobisquit%2Fpaperwok'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b2abb5171be214ae69ae329c414c7d1931278c0f
[INFO] testing lobisquit/paperwok against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flobisquit%2Fpaperwok" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/lobisquit/paperwok 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/lobisquit/paperwok
[INFO] finished tweaking git repo https://github.com/lobisquit/paperwok
[INFO] tweaked toml for git repo https://github.com/lobisquit/paperwok written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/lobisquit/paperwok 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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] 4968ca29d02513487719cb5a104c1c5f2eaffbf0f3866e759941922569f2ba19
[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" "4968ca29d02513487719cb5a104c1c5f2eaffbf0f3866e759941922569f2ba19", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4968ca29d02513487719cb5a104c1c5f2eaffbf0f3866e759941922569f2ba19", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4968ca29d02513487719cb5a104c1c5f2eaffbf0f3866e759941922569f2ba19", kill_on_drop: false }`
[INFO] [stdout] 4968ca29d02513487719cb5a104c1c5f2eaffbf0f3866e759941922569f2ba19
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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] 52909aa554a910f0e465978919430b2dedf949ad4f77993cdaa2f44aa9cf278d
[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" "52909aa554a910f0e465978919430b2dedf949ad4f77993cdaa2f44aa9cf278d", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.36
[INFO] [stderr]    Compiling cfg-if v0.1.2
[INFO] [stderr]    Compiling version_check v0.1.3
[INFO] [stderr]    Compiling lazy_static v1.0.0
[INFO] [stderr]    Compiling gcc v0.3.54
[INFO] [stderr]    Compiling yansi v0.3.4
[INFO] [stderr]    Compiling rayon-core v1.4.0
[INFO] [stderr]    Compiling num-traits v0.2.0
[INFO] [stderr]    Compiling byteorder v1.2.1
[INFO] [stderr]    Compiling serde v1.0.27
[INFO] [stderr]    Compiling unicode-normalization v0.1.5
[INFO] [stderr]    Compiling cc v1.0.4
[INFO] [stderr]    Compiling untrusted v0.5.1
[INFO] [stderr]    Compiling httparse v1.2.4
[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/yansi-0.3.4/src/lib.rs:1:32
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(feature="nightly", feature(const_atomic_bool_new))]
[INFO] [stdout]   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling typeable v0.1.2
[INFO] [stderr]    Compiling traitobject v0.1.0
[INFO] [stderr]    Compiling regex-syntax v0.4.2
[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 `yansi`
[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" "52909aa554a910f0e465978919430b2dedf949ad4f77993cdaa2f44aa9cf278d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "52909aa554a910f0e465978919430b2dedf949ad4f77993cdaa2f44aa9cf278d", kill_on_drop: false }`
[INFO] [stdout] 52909aa554a910f0e465978919430b2dedf949ad4f77993cdaa2f44aa9cf278d