[INFO] fetching crate racer 2.1.43...
[INFO] checking racer-2.1.43 against try#9c1dcf141bc0875407c4eb36972857bd3db713e2 for pr-81863
[INFO] extracting crate racer 2.1.43 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate racer 2.1.43 on toolchain 9c1dcf141bc0875407c4eb36972857bd3db713e2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate racer 2.1.43
[INFO] finished tweaking crates.io crate racer 2.1.43
[INFO] tweaked toml for crates.io crate racer 2.1.43 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate racer 2.1.43 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded racer v2.1.42
[INFO] [stderr]   Downloaded rustc-ap-rustc_ast_pretty v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_serialize v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_lexer v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_lint_defs v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_arena v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_macros v697.0.0
[INFO] [stderr]   Downloaded psm v0.1.8
[INFO] [stderr]   Downloaded rustc-ap-rustc_span v697.0.0
[INFO] [stderr]   Downloaded rls-span v0.5.2
[INFO] [stderr]   Downloaded rustc-ap-rustc_parse v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_errors v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_feature v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_fs_util v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_ast v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_target v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_session v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_graphviz v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_data_structures v697.0.0
[INFO] [stderr]   Downloaded rustc-ap-rustc_index v697.0.0
[INFO] [stderr]   Downloaded racer-testutils v0.1.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 92b5a121d0a92eca2a1618b17c90d00aeb0bed1f6d403edc10a2ec96d67cb348
[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" "92b5a121d0a92eca2a1618b17c90d00aeb0bed1f6d403edc10a2ec96d67cb348", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "92b5a121d0a92eca2a1618b17c90d00aeb0bed1f6d403edc10a2ec96d67cb348", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "92b5a121d0a92eca2a1618b17c90d00aeb0bed1f6d403edc10a2ec96d67cb348", kill_on_drop: false }`
[INFO] [stdout] 92b5a121d0a92eca2a1618b17c90d00aeb0bed1f6d403edc10a2ec96d67cb348
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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=forbid" "-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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f3d88305d1f196d8c0b48fcf8a3ffe0a6c0c44a7c3b1e22ae47ba99503284a46
[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" "f3d88305d1f196d8c0b48fcf8a3ffe0a6c0c44a7c3b1e22ae47ba99503284a46", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.77
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking smallvec v1.4.2
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling rustc-rayon-core v0.3.0
[INFO] [stderr]     Checking rustc-hash v1.1.0
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking scoped-tls v1.0.0
[INFO] [stderr]     Checking unicode-xid v0.2.0
[INFO] [stderr]     Checking rustc-ap-rustc_graphviz v702.0.0
[INFO] [stderr]     Checking rustc-ap-rustc_graphviz v697.0.0
[INFO] [stderr]     Checking annotate-snippets v0.8.0
[INFO] [stderr]    Compiling ryu v1.0.3
[INFO] [stderr]     Checking vec_map v0.8.1
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking rustc-ap-rustc_fs_util v697.0.0
[INFO] [stderr]     Checking humantime v2.0.0
[INFO] [stderr]     Checking rustc-ap-rustc_fs_util v702.0.0
[INFO] [stderr]    Compiling hashbrown v0.8.2
[INFO] [stderr]    Compiling indexmap v1.5.2
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling psm v0.1.8
[INFO] [stderr]     Checking instant v0.1.7
[INFO] [stderr]    Compiling stacker v0.1.12
[INFO] [stderr]     Checking getopts v0.2.21
[INFO] [stderr]     Checking lock_api v0.4.1
[INFO] [stderr]     Checking rustc-ap-rustc_lexer v702.0.0
[INFO] [stderr]     Checking rustc-ap-rustc_lexer v697.0.0
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]     Checking tracing-core v0.1.15
[INFO] [stderr]     Checking thread_local v1.0.1
[INFO] [stderr]    Compiling proc-macro2 v1.0.10
[INFO] [stderr]     Checking rustc-ap-rustc_arena v697.0.0
[INFO] [stderr]     Checking rustc-ap-rustc_arena v702.0.0
[INFO] [stderr]     Checking unicode-normalization v0.1.12
[INFO] [stderr]     Checking ena v0.14.0
[INFO] [stderr]     Checking aho-corasick v0.7.10
[INFO] [stderr]     Checking block-buffer v0.9.0
[INFO] [stdout] error[E0635]: unknown feature `array_value_iter_slice`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/rustc-ap-rustc_arena-697.0.0/src/lib.rs:14:12
[INFO] [stdout]    |
[INFO] [stdout] 14 | #![feature(array_value_iter_slice)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking digest v0.9.0
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rustc-ap-rustc_arena`
[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] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "f3d88305d1f196d8c0b48fcf8a3ffe0a6c0c44a7c3b1e22ae47ba99503284a46", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f3d88305d1f196d8c0b48fcf8a3ffe0a6c0c44a7c3b1e22ae47ba99503284a46", kill_on_drop: false }`
[INFO] [stdout] f3d88305d1f196d8c0b48fcf8a3ffe0a6c0c44a7c3b1e22ae47ba99503284a46