[INFO] cloning repository https://github.com/racer-rust/racer
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/racer-rust/racer" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fracer-rust%2Fracer", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fracer-rust%2Fracer'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a4bcf46c7a908eb53eeb69ec421c5ee44e879902
[INFO] testing racer-rust/racer against 1.45.2 for beta-1.46-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fracer-rust%2Fracer" "/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/racer-rust/racer 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/racer-rust/racer
[INFO] removed workspace from git repo https://github.com/racer-rust/racer
[INFO] removed path dependency racer-cargo-metadata from git repo https://github.com/racer-rust/racer
[INFO] removed path dependency racer-testutils from git repo https://github.com/racer-rust/racer
[INFO] finished tweaking git repo https://github.com/racer-rust/racer
[INFO] tweaked toml for git repo https://github.com/racer-rust/racer written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/racer-rust/racer 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] [stderr]     Updating crates.io index
[INFO] [stderr] error: the lock file /workspace/builds/worker-4/source/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] [stderr] If you want to try to generate the lock file without accessing the network, use the --offline flag.
[INFO] the lockfile is outdated, regenerating it
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "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" "+1.45.2" "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] eb54e1987b1b70a63009ae8fd969505ebfd349de24e995749368013b2b491331
[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" "eb54e1987b1b70a63009ae8fd969505ebfd349de24e995749368013b2b491331", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "eb54e1987b1b70a63009ae8fd969505ebfd349de24e995749368013b2b491331", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eb54e1987b1b70a63009ae8fd969505ebfd349de24e995749368013b2b491331", kill_on_drop: false }`
[INFO] [stdout] eb54e1987b1b70a63009ae8fd969505ebfd349de24e995749368013b2b491331
[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] eb6cee8058090cd782dab080dbfce16c9214ae26b396bb0fad2ce688c0a8465f
[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" "eb6cee8058090cd782dab080dbfce16c9214ae26b396bb0fad2ce688c0a8465f", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.38
[INFO] [stderr]    Compiling smallvec v1.4.1
[INFO] [stderr]    Compiling typenum v1.12.0
[INFO] [stderr]    Compiling rustc-rayon-core v0.3.0
[INFO] [stderr]    Compiling byte-tools v0.3.1
[INFO] [stderr]    Compiling rustc-hash v1.1.0
[INFO] [stderr]    Compiling arrayvec v0.5.1
[INFO] [stderr]    Compiling either v1.5.3
[INFO] [stderr]    Compiling rustc-ap-rustc_graphviz v671.0.0
[INFO] [stderr]    Compiling opaque-debug v0.2.3
[INFO] [stderr]    Compiling stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling fake-simd v0.1.2
[INFO] [stderr]    Compiling scoped-tls v1.0.0
[INFO] [stderr]    Compiling termcolor v1.1.0
[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/rustc-ap-rustc_graphviz-671.0.0/lib.rs:278:1
[INFO] [stdout]     |
[INFO] [stdout] 278 | #![feature(rustc_private, nll)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling annotate-snippets v0.8.0
[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/smallvec-1.4.1/lib.rs:74:32
[INFO] [stdout]    |
[INFO] [stdout] 74 | #![cfg_attr(feature = "union", feature(untagged_unions))]
[INFO] [stdout]    |                                ^^^^^^^^^^^^^^^^^^^^^^^^
[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/smallvec-1.4.1/lib.rs:76:37
[INFO] [stdout]    |
[INFO] [stdout] 76 | #![cfg_attr(feature = "may_dangle", feature(dropck_eyepatch))]
[INFO] [stdout]    |                                     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rustc-ap-rustc_fs_util v671.0.0
[INFO] [stderr]    Compiling lazycell v1.2.1
[INFO] [stderr]    Compiling humantime v2.0.1
[INFO] [stderr]    Compiling memoffset v0.5.5
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[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]    Compiling hashbrown v0.8.2
[INFO] [stderr] error: could not compile `rustc-ap-rustc_graphviz`.
[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: aborting due to 2 previous errors
[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" "eb6cee8058090cd782dab080dbfce16c9214ae26b396bb0fad2ce688c0a8465f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eb6cee8058090cd782dab080dbfce16c9214ae26b396bb0fad2ce688c0a8465f", kill_on_drop: false }`
[INFO] [stdout] eb6cee8058090cd782dab080dbfce16c9214ae26b396bb0fad2ce688c0a8465f