[INFO] fetching crate mutagen-plugin 0.1.2...
[INFO] documenting mutagen-plugin-0.1.2 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate mutagen-plugin 0.1.2 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate mutagen-plugin 0.1.2 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 mutagen-plugin 0.1.2
[INFO] finished tweaking crates.io crate mutagen-plugin 0.1.2
[INFO] tweaked toml for crates.io crate mutagen-plugin 0.1.2 written to /workspace/builds/worker-9/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] [stderr]     Blocking waiting for file lock on package cache
[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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] d72469a24b1334d9b06f040d0bec8b11548f897a810d656d168daee9e221acc2
[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" "d72469a24b1334d9b06f040d0bec8b11548f897a810d656d168daee9e221acc2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d72469a24b1334d9b06f040d0bec8b11548f897a810d656d168daee9e221acc2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d72469a24b1334d9b06f040d0bec8b11548f897a810d656d168daee9e221acc2", kill_on_drop: false }`
[INFO] [stdout] d72469a24b1334d9b06f040d0bec8b11548f897a810d656d168daee9e221acc2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] afa5b40cb0c4616d50a396a76389539f0ff3076a1a8f36b24b1e3f3f79f15f0d
[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" "afa5b40cb0c4616d50a396a76389539f0ff3076a1a8f36b24b1e3f3f79f15f0d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling mutagen v0.1.2
[INFO] [stderr]    Compiling mutagen-plugin v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> build.rs:15:30
[INFO] [stdout]    |
[INFO] [stdout] 15 | fn write_binop_arm(out: &mut Write,
[INFO] [stdout]    |                              ^^^^^ help: use `dyn`: `dyn Write`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> build.rs:59:33
[INFO] [stdout]    |
[INFO] [stdout] 59 | fn write_opassign_arm(out: &mut Write,
[INFO] [stdout]    |                                 ^^^^^ help: use `dyn`: `dyn Write`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[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/mutagen-0.1.2/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization, atomic_min_max, try_from, assoc_unix_epoch)]
[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 `mutagen`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "afa5b40cb0c4616d50a396a76389539f0ff3076a1a8f36b24b1e3f3f79f15f0d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "afa5b40cb0c4616d50a396a76389539f0ff3076a1a8f36b24b1e3f3f79f15f0d", kill_on_drop: false }`
[INFO] [stdout] afa5b40cb0c4616d50a396a76389539f0ff3076a1a8f36b24b1e3f3f79f15f0d