[INFO] fetching crate racer 2.1.48...
[INFO] testing racer-2.1.48 against 1.55.0 for beta-1.56-1
[INFO] extracting crate racer 2.1.48 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate racer 2.1.48 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-11/source/rust-toolchain.toml
[INFO] started tweaking crates.io crate racer 2.1.48
[INFO] finished tweaking crates.io crate racer 2.1.48
[INFO] tweaked toml for crates.io crate racer 2.1.48 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate crates.io crate racer 2.1.48 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tracing-core v0.1.15
[INFO] [stderr]   Downloaded cloudabi v0.1.0
[INFO] [stderr]   Downloaded serde_json v1.0.50
[INFO] [stderr]   Downloaded hermit-abi v0.1.10
[INFO] [stderr]   Downloaded proc-macro2 v1.0.10
[INFO] [stderr]   Downloaded regex v1.3.6
[INFO] [stderr]   Downloaded rustc-ap-rustc_fs_util v718.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_lexer v718.0.0
[INFO] [stderr]   Downloaded parking_lot_core v0.8.0
[INFO] [stderr]   Downloaded arrayvec v0.7.0
[INFO] [stderr]   Downloaded tracing-attributes v0.1.11
[INFO] [stderr]   Downloaded racer-testutils v0.1.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_ast_pretty v718.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_target v718.0.0
[INFO] [stderr]   Downloaded derive_more v0.99.5
[INFO] [stderr]   Downloaded rustc-ap-rustc_ast v718.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_errors v718.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_graphviz v718.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_macros v718.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_session v718.0.0
[INFO] [stderr]   Downloaded memmap2 v0.2.2
[INFO] [stderr]   Downloaded measureme v9.1.0
[INFO] [stderr]   Downloaded parking_lot v0.11.0
[INFO] [stderr]   Downloaded tracing v0.1.19
[INFO] [stderr]   Downloaded sha2 v0.9.2
[INFO] [stderr]   Downloaded rustc-ap-rustc_parse v718.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_data_structures v718.0.0
[INFO] [stderr]   Downloaded racer v2.1.47
[INFO] [stderr]   Downloaded rustc-ap-rustc_feature v718.0.0
[INFO] [stderr]   Downloaded rls-span v0.5.2
[INFO] [stderr]   Downloaded rustc-ap-rustc_serialize v718.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_span v718.0.0
[INFO] [stderr]   Downloaded winapi-util v0.1.4
[INFO] [stderr]   Downloaded psm v0.1.8
[INFO] [stderr]   Downloaded rustc-ap-rustc_arena v718.0.0
[INFO] [stderr]   Downloaded indexmap v1.5.2
[INFO] [stderr]   Downloaded rustc-ap-rustc_index v718.0.0
[INFO] [stderr]   Downloaded stacker v0.1.12
[INFO] [stderr]   Downloaded instant v0.1.7
[INFO] [stderr]   Downloaded sha-1 v0.9.2
[INFO] [stderr]   Downloaded cc v1.0.53
[INFO] [stderr]   Downloaded rustc-ap-rustc_lint_defs v718.0.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5d9ac11cc7b34d3329863d5eef385d6c2f0b759afac6f52694ba18b2c9262e37
[INFO] running `Command { std: "docker" "start" "-a" "5d9ac11cc7b34d3329863d5eef385d6c2f0b759afac6f52694ba18b2c9262e37", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5d9ac11cc7b34d3329863d5eef385d6c2f0b759afac6f52694ba18b2c9262e37", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5d9ac11cc7b34d3329863d5eef385d6c2f0b759afac6f52694ba18b2c9262e37", kill_on_drop: false }`
[INFO] [stdout] 5d9ac11cc7b34d3329863d5eef385d6c2f0b759afac6f52694ba18b2c9262e37
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fd46b6205ef3af783fad487a2acc7daad11cfdfbab9b930804d2a5dd6e7d352b
[INFO] running `Command { std: "docker" "start" "-a" "fd46b6205ef3af783fad487a2acc7daad11cfdfbab9b930804d2a5dd6e7d352b", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.77
[INFO] [stderr]    Compiling proc-macro2 v1.0.10
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling cc v1.0.53
[INFO] [stderr]    Compiling smallvec v1.6.1
[INFO] [stderr]    Compiling rustc-rayon-core v0.3.1
[INFO] [stderr]    Compiling arrayvec v0.7.0
[INFO] [stderr]    Compiling remove_dir_all v0.5.2
[INFO] [stderr]    Compiling rustc-ap-rustc_graphviz v722.0.0
[INFO] [stderr]    Compiling stable_deref_trait v1.1.1
[INFO] [stderr]    Compiling cpuid-bool v0.1.2
[INFO] [stderr]    Compiling serde v1.0.105
[INFO] [stderr]    Compiling annotate-snippets v0.8.0
[INFO] [stderr]    Compiling rustc-ap-rustc_fs_util v722.0.0
[INFO] [stderr]    Compiling humantime v2.0.0
[INFO] [stderr]    Compiling hashbrown v0.8.2
[INFO] [stderr]    Compiling indexmap v1.5.2
[INFO] [stderr]    Compiling crossbeam-utils v0.8.4
[INFO] [stderr]    Compiling generic-array v0.14.4
[INFO] [stderr]    Compiling tracing-core v0.1.15
[INFO] [stderr]    Compiling rustc-ap-rustc_lexer v722.0.0
[INFO] [stderr]    Compiling getopts v0.2.21
[INFO] [stderr]    Compiling ena v0.14.0
[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-722.0.0/src/lib.rs:278:1
[INFO] [stdout]     |
[INFO] [stdout] 278 | #![feature(nll)]
[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-1.6.1/src/lib.rs:76:37
[INFO] [stdout]    |
[INFO] [stdout] 76 | #![cfg_attr(feature = "may_dangle", feature(dropck_eyepatch))]
[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 `rustc-ap-rustc_graphviz` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[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" "fd46b6205ef3af783fad487a2acc7daad11cfdfbab9b930804d2a5dd6e7d352b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fd46b6205ef3af783fad487a2acc7daad11cfdfbab9b930804d2a5dd6e7d352b", kill_on_drop: false }`
[INFO] [stdout] fd46b6205ef3af783fad487a2acc7daad11cfdfbab9b930804d2a5dd6e7d352b