[INFO] fetching crate expert 0.0.1...
[INFO] testing expert-0.0.1 against 1.49.0 for beta-1.50-1
[INFO] extracting crate expert 0.0.1 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate expert 0.0.1 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 crates.io crate expert 0.0.1
[INFO] finished tweaking crates.io crate expert 0.0.1
[INFO] tweaked toml for crates.io crate expert 0.0.1 written to /workspace/builds/worker-6/source/Cargo.toml
[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]  Downloading crates ...
[INFO] [stderr]   Downloaded string-interner v0.6.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1cc0196a396faf41ba9a5f77dd1b13f9d191a13a02237d18c1478bd0294e6b43
[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" "1cc0196a396faf41ba9a5f77dd1b13f9d191a13a02237d18c1478bd0294e6b43", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1cc0196a396faf41ba9a5f77dd1b13f9d191a13a02237d18c1478bd0294e6b43", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1cc0196a396faf41ba9a5f77dd1b13f9d191a13a02237d18c1478bd0294e6b43", kill_on_drop: false }`
[INFO] [stdout] 1cc0196a396faf41ba9a5f77dd1b13f9d191a13a02237d18c1478bd0294e6b43
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a49fbfce065f8257fa7c6cbf0af522e5d47183675b2b6ead881589161740c864
[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" "a49fbfce065f8257fa7c6cbf0af522e5d47183675b2b6ead881589161740c864", kill_on_drop: false }`
[INFO] [stderr]    Compiling interpolate_idents v0.1.8
[INFO] [stderr]    Compiling unreachable v1.0.0
[INFO] [stderr]    Compiling owning_ref v0.3.3
[INFO] [stderr]    Compiling string-interner v0.6.4
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-complex v0.1.43
[INFO] [stderr]    Compiling parking_lot_core v0.2.14
[INFO] [stdout] error[E0462]: found staticlib `rustc` instead of rlib or dylib
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/interpolate_idents-0.1.8/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | extern crate rustc;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: please recompile that crate using --crate-type lib
[INFO] [stdout]   = note: the following crate versions were found:
[INFO] [stdout]           crate `rustc`: /opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc-stable_rt.tsan.a
[INFO] [stdout]           crate `rustc`: /opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc-stable_rt.msan.a
[INFO] [stdout]           crate `rustc`: /opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc-stable_rt.asan.a
[INFO] [stdout]           crate `rustc`: /opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc-stable_rt.lsan.a
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `interpolate_idents`
[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] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/parking_lot_core-0.2.14/src/lib.rs:41:60
[INFO] [stdout]    |
[INFO] [stdout] 41 | #![cfg_attr(all(feature = "nightly", target_os = "linux"), feature(integer_atomics))]
[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: build failed
[INFO] running `Command { std: "docker" "inspect" "a49fbfce065f8257fa7c6cbf0af522e5d47183675b2b6ead881589161740c864", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a49fbfce065f8257fa7c6cbf0af522e5d47183675b2b6ead881589161740c864", kill_on_drop: false }`
[INFO] [stdout] a49fbfce065f8257fa7c6cbf0af522e5d47183675b2b6ead881589161740c864