[INFO] fetching crate racer 2.1.36...
[INFO] testing racer-2.1.36 against beta-2020-07-24 for beta-1.46-1
[INFO] extracting crate racer 2.1.36 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate racer 2.1.36 on toolchain beta-2020-07-24
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate racer 2.1.36
[INFO] finished tweaking crates.io crate racer 2.1.36
[INFO] tweaked toml for crates.io crate racer 2.1.36 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate crates.io crate racer 2.1.36 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "+beta-2020-07-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1203e3e645272a523ced7f1b228f550325873f1ab468aef56e113315bd4fd356
[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" "1203e3e645272a523ced7f1b228f550325873f1ab468aef56e113315bd4fd356", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1203e3e645272a523ced7f1b228f550325873f1ab468aef56e113315bd4fd356", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1203e3e645272a523ced7f1b228f550325873f1ab468aef56e113315bd4fd356", kill_on_drop: false }`
[INFO] [stdout] 1203e3e645272a523ced7f1b228f550325873f1ab468aef56e113315bd4fd356
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "+beta-2020-07-24" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 31f08934acc90d7c5fbf6565407b16d8ce9aba3e3e7b851ae5649844382dc2a5
[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" "31f08934acc90d7c5fbf6565407b16d8ce9aba3e3e7b851ae5649844382dc2a5", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.68
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling smallvec v1.2.0
[INFO] [stderr]    Compiling rustc-rayon-core v0.3.0
[INFO] [stderr]    Compiling rustc-ap-rustc_graphviz v669.0.0
[INFO] [stderr]    Compiling stable_deref_trait v1.1.1
[INFO] [stderr]    Compiling serde v1.0.105
[INFO] [stderr]    Compiling rustc-ap-rustc_ast v669.0.0
[INFO] [stderr]    Compiling rustc-ap-rustc_target v669.0.0
[INFO] [stderr]    Compiling ryu v1.0.3
[INFO] [stderr]    Compiling annotate-snippets v0.8.0
[INFO] [stderr]    Compiling rustc-ap-rustc_fs_util v669.0.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling lock_api v0.3.4
[INFO] [stderr]    Compiling psm v0.1.8
[INFO] [stderr]    Compiling stacker v0.1.9
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/smallvec-1.2.0/lib.rs:29:32
[INFO] [stdout]    |
[INFO] [stdout] 29 | #![cfg_attr(feature = "union", feature(untagged_unions))]
[INFO] [stdout]    |                                ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/smallvec-1.2.0/lib.rs:31:37
[INFO] [stdout]    |
[INFO] [stdout] 31 | #![cfg_attr(feature = "may_dangle", feature(dropck_eyepatch))]
[INFO] [stdout]    |                                     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/rustc-ap-rustc_graphviz-669.0.0/lib.rs:278:1
[INFO] [stdout]     |
[INFO] [stdout] 278 | #![feature(rustc_private, nll)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rustc-ap-rustc_lexer v669.0.0
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lock_api-0.3.4/src/lib.rs:91:34
[INFO] [stdout]    |
[INFO] [stdout] 91 | #![cfg_attr(feature = "nightly", feature(const_fn))]
[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]    Compiling getopts v0.2.21
[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] [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" "31f08934acc90d7c5fbf6565407b16d8ce9aba3e3e7b851ae5649844382dc2a5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "31f08934acc90d7c5fbf6565407b16d8ce9aba3e3e7b851ae5649844382dc2a5", kill_on_drop: false }`
[INFO] [stdout] 31f08934acc90d7c5fbf6565407b16d8ce9aba3e3e7b851ae5649844382dc2a5