[INFO] updating cached repository https://github.com/swfsql/structopt-external-doc
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 9953bdc159513170d9230f8e0d6f691804e95f3b
[INFO] testing swfsql/structopt-external-doc against 1.45.2 for beta-1.46-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fswfsql%2Fstructopt-external-doc" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/swfsql/structopt-external-doc on toolchain 1.45.2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/swfsql/structopt-external-doc
[INFO] finished tweaking git repo https://github.com/swfsql/structopt-external-doc
[INFO] tweaked toml for git repo https://github.com/swfsql/structopt-external-doc written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/swfsql/structopt-external-doc already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "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-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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0a86523db7da226c923bbd8b6be7f10f23e6fc6598f9423a8c236b00448fe970
[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" "0a86523db7da226c923bbd8b6be7f10f23e6fc6598f9423a8c236b00448fe970", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0a86523db7da226c923bbd8b6be7f10f23e6fc6598f9423a8c236b00448fe970", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0a86523db7da226c923bbd8b6be7f10f23e6fc6598f9423a8c236b00448fe970", kill_on_drop: false }`
[INFO] [stdout] 0a86523db7da226c923bbd8b6be7f10f23e6fc6598f9423a8c236b00448fe970
[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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6e7558258254bc5ff0770ddecb7d1150f92b5b519e49d5442d486931b2a2c5c6
[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" "6e7558258254bc5ff0770ddecb7d1150f92b5b519e49d5442d486931b2a2c5c6", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.72
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.3
[INFO] [stderr]    Compiling proc-macro-error v1.0.3
[INFO] [stderr]    Compiling syn v1.0.33
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling clap v2.33.1
[INFO] [stderr]    Compiling syn-mid v0.5.0
[INFO] [stderr]    Compiling structopt-derive v0.4.8 (https://github.com/swfsql/structopt?rev=6e400fa#6e400fac)
[INFO] [stderr]    Compiling structopt v0.3.15 (https://github.com/swfsql/structopt?rev=6e400fa#6e400fac)
[INFO] [stderr]    Compiling structopt-external-doc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(external_doc)]
[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 `structopt-external-doc`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "6e7558258254bc5ff0770ddecb7d1150f92b5b519e49d5442d486931b2a2c5c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6e7558258254bc5ff0770ddecb7d1150f92b5b519e49d5442d486931b2a2c5c6", kill_on_drop: false }`
[INFO] [stdout] 6e7558258254bc5ff0770ddecb7d1150f92b5b519e49d5442d486931b2a2c5c6