[INFO] fetching crate lsp_rs 0.1.0...
[INFO] testing lsp_rs-0.1.0 against 1.49.0 for beta-1.50-1
[INFO] extracting crate lsp_rs 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate lsp_rs 0.1.0 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 lsp_rs 0.1.0
[INFO] finished tweaking crates.io crate lsp_rs 0.1.0
[INFO] tweaked toml for crates.io crate lsp_rs 0.1.0 written to /workspace/builds/worker-4/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] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "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-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" "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] e04086026bb99d534a5eafb2b2e31d8173632208c383a8323797915714ef6807
[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" "e04086026bb99d534a5eafb2b2e31d8173632208c383a8323797915714ef6807", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e04086026bb99d534a5eafb2b2e31d8173632208c383a8323797915714ef6807", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e04086026bb99d534a5eafb2b2e31d8173632208c383a8323797915714ef6807", kill_on_drop: false }`
[INFO] [stdout] e04086026bb99d534a5eafb2b2e31d8173632208c383a8323797915714ef6807
[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" "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] a3e5cdcabde18d453e369404731f7a2d824a9d18b7bfb587e4c370243590068a
[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" "a3e5cdcabde18d453e369404731f7a2d824a9d18b7bfb587e4c370243590068a", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v0.8.23
[INFO] [stderr]    Compiling itoa v0.1.1
[INFO] [stderr]    Compiling dtoa v0.2.2
[INFO] [stderr]    Compiling syn v0.10.8
[INFO] [stderr]    Compiling tokio-io v0.1.13
[INFO] [stderr]    Compiling tokio-threadpool v0.1.18
[INFO] [stderr]    Compiling mio-uds v0.6.8
[INFO] [stderr]    Compiling enum_primitive v0.1.1
[INFO] [stderr]    Compiling tokio-reactor v0.1.12
[INFO] [stderr]    Compiling tokio-codec v0.1.2
[INFO] [stderr]    Compiling tokio-fs v0.1.7
[INFO] [stderr]    Compiling tokio-uds v0.2.7
[INFO] [stderr]    Compiling tokio-tcp v0.1.4
[INFO] [stderr]    Compiling tokio-udp v0.1.6
[INFO] [stderr]    Compiling serde_codegen_internals v0.11.3
[INFO] [stderr]    Compiling tokio v0.1.22
[INFO] [stderr]    Compiling serde_codegen v0.8.23
[INFO] [stderr]    Compiling tokio-core v0.1.18
[INFO] [stderr]    Compiling url v1.7.2
[INFO] [stderr]    Compiling serde_json v0.8.6
[INFO] [stderr]    Compiling erased-serde v0.1.3
[INFO] [stderr]    Compiling serde_derive v0.8.23
[INFO] [stderr]    Compiling languageserver-types v0.6.1
[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/languageserver-types-0.6.1/src/lib.rs:22:1
[INFO] [stdout]    |
[INFO] [stdout] 22 | #![feature(proc_macro)]
[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 `languageserver-types`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "a3e5cdcabde18d453e369404731f7a2d824a9d18b7bfb587e4c370243590068a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a3e5cdcabde18d453e369404731f7a2d824a9d18b7bfb587e4c370243590068a", kill_on_drop: false }`
[INFO] [stdout] a3e5cdcabde18d453e369404731f7a2d824a9d18b7bfb587e4c370243590068a