[INFO] fetching crate mech-server 0.0.4...
[INFO] testing mech-server-0.0.4 against 1.54.0 for beta-1.55-1
[INFO] extracting crate mech-server 0.0.4 into /workspace/builds/worker-103/source
[INFO] validating manifest of crates.io crate mech-server 0.0.4 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mech-server 0.0.4
[INFO] finished tweaking crates.io crate mech-server 0.0.4
[INFO] tweaked toml for crates.io crate mech-server 0.0.4 written to /workspace/builds/worker-103/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "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" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-103/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-103/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3d842985de0a5e364f9280da2a3c53125aa60669feb80a347798f556440f7468
[INFO] running `Command { std: "docker" "start" "-a" "3d842985de0a5e364f9280da2a3c53125aa60669feb80a347798f556440f7468", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3d842985de0a5e364f9280da2a3c53125aa60669feb80a347798f556440f7468", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3d842985de0a5e364f9280da2a3c53125aa60669feb80a347798f556440f7468", kill_on_drop: false }`
[INFO] [stdout] 3d842985de0a5e364f9280da2a3c53125aa60669feb80a347798f556440f7468
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-103/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-103/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a936e40a9e83cc8b072fd47dc9081b761efc7a88e22bc9c504fd9750befac9e2
[INFO] running `Command { std: "docker" "start" "-a" "a936e40a9e83cc8b072fd47dc9081b761efc7a88e22bc9c504fd9750befac9e2", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.98
[INFO] [stderr]    Compiling byteorder v1.4.3
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling proc-macro2 v1.0.28
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling futures v0.1.31
[INFO] [stderr]    Compiling cc v1.0.69
[INFO] [stderr]    Compiling tinyvec_macros v0.1.0
[INFO] [stderr]    Compiling matches v0.1.8
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling version_check v0.1.5
[INFO] [stderr]    Compiling serde_derive v1.0.127
[INFO] [stderr]    Compiling slab v0.4.4
[INFO] [stderr]    Compiling serde v1.0.127
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling httparse v1.4.1
[INFO] [stderr]    Compiling fnv v1.0.7
[INFO] [stderr]    Compiling memchr v2.4.0
[INFO] [stderr]    Compiling itoa v0.4.7
[INFO] [stderr]    Compiling siphasher v0.2.3
[INFO] [stderr]    Compiling pkg-config v0.3.19
[INFO] [stderr]    Compiling percent-encoding v1.0.1
[INFO] [stderr]    Compiling traitobject v0.1.0
[INFO] [stderr]    Compiling adler v1.0.2
[INFO] [stderr]    Compiling percent-encoding v2.1.0
[INFO] [stderr]    Compiling foreign-types-shared v0.1.1
[INFO] [stderr]    Compiling hashbrown v0.11.2
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling openssl v0.10.35
[INFO] [stderr]    Compiling gimli v0.25.0
[INFO] [stderr]    Compiling native-tls v0.2.7
[INFO] [stderr]    Compiling try-lock v0.2.3
[INFO] [stderr]    Compiling serde_json v1.0.66
[INFO] [stderr]    Compiling lexical-core v0.7.6
[INFO] [stderr]    Compiling rustc-demangle v0.1.20
[INFO] [stderr]    Compiling crc32fast v1.2.1
[INFO] [stderr]    Compiling ahash v0.3.8
[INFO] [stderr]    Compiling safemem v0.3.3
[INFO] [stderr]    Compiling typeable v0.1.2
[INFO] [stderr]    Compiling language-tags v0.2.2
[INFO] [stderr]    Compiling openssl-probe v0.1.4
[INFO] [stderr]    Compiling byte-tools v0.3.1
[INFO] [stderr]    Compiling encoding_rs v0.8.28
[INFO] [stderr]    Compiling arrayvec v0.5.2
[INFO] [stderr]    Compiling dtoa v0.4.8
[INFO] [stderr]    Compiling modifier v0.1.0
[INFO] [stderr]    Compiling mime v0.3.16
[INFO] [stderr]    Compiling lazycell v1.3.0
[INFO] [stderr]    Compiling sequence_trie v0.3.6
[INFO] [stderr]    Compiling fake-simd v0.1.2
[INFO] [stderr]    Compiling opaque-debug v0.2.3
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling term v0.4.6
[INFO] [stderr]    Compiling same-file v0.1.3
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling ansi_term v0.11.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.6
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]    Compiling indexmap v1.7.0
[INFO] [stderr]    Compiling unicase v2.6.0
[INFO] [stderr]    Compiling hashbrown v0.7.2
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling nom v5.1.2
[INFO] [stderr]    Compiling try_from v0.3.2
[INFO] [stderr]    Compiling log v0.3.9
[INFO] [stderr]    Compiling generic-array v0.12.4
[INFO] [stderr]    Compiling tinyvec v1.3.1
[INFO] [stderr]    Compiling unicode-bidi v0.3.5
[INFO] [stderr]    Compiling lock_api v0.3.4
[INFO] [stderr]    Compiling foreign-types v0.3.2
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand_jitter v0.1.4
[INFO] [stderr]    Compiling form_urlencoded v1.0.1
[INFO] [stderr]    Compiling unsafe-any v0.4.2
[INFO] [stderr]    Compiling base64 v0.9.3
[INFO] [stderr]    Compiling base64 v0.10.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling typemap v0.3.3
[INFO] [stderr]    Compiling block-padding v0.1.5
[INFO] [stderr]    Compiling mime v0.2.6
[INFO] [stderr]    Compiling digest v0.8.1
[INFO] [stderr]    Compiling walkdir v1.0.7
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling unicase v1.4.2
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling term-painter v0.2.4
[INFO] [stderr]    Compiling tokio-sync v0.1.8
[INFO] [stderr]    Compiling want v0.2.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling openssl-sys v0.9.65
[INFO] [stderr]    Compiling backtrace v0.3.61
[INFO] [stderr]    Compiling libloading v0.5.2
[INFO] [stderr]    Compiling block-buffer v0.7.3
[INFO] [stderr]    Compiling plugin v0.2.6
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling time v0.1.44
[INFO] [stderr]    Compiling net2 v0.2.37
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling smallvec v0.6.14
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling hyper v0.12.36
[INFO] [stderr]    Compiling addr2line v0.16.0
[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/hashbrown-0.7.2/src/lib.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 | /     feature(
[INFO] [stdout] 16 | |         alloc_layout_extra,
[INFO] [stdout] 17 | |         allocator_api,
[INFO] [stdout] 18 | |         ptr_offset_from,
[INFO] [stdout] ...  |
[INFO] [stdout] 22 | |         specialization,
[INFO] [stdout] 23 | |     )
[INFO] [stdout]    | |_____^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling object v0.26.0
[INFO] [stderr]    Compiling bytes v0.4.12
[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 mio v0.6.23
[INFO] [stderr]    Compiling futures-cpupool v0.1.8
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr] error: could not compile `hashbrown`
[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" "a936e40a9e83cc8b072fd47dc9081b761efc7a88e22bc9c504fd9750befac9e2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a936e40a9e83cc8b072fd47dc9081b761efc7a88e22bc9c504fd9750befac9e2", kill_on_drop: false }`
[INFO] [stdout] a936e40a9e83cc8b072fd47dc9081b761efc7a88e22bc9c504fd9750befac9e2
