[INFO] fetching crate relp-num 0.1.8...
[INFO] checking relp-num-0.1.8 against 1.55.0 for beta-1.56-3
[INFO] extracting crate relp-num 0.1.8 into /workspace/builds/worker-107/source
[INFO] validating manifest of crates.io crate relp-num 0.1.8 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] started tweaking crates.io crate relp-num 0.1.8
[INFO] finished tweaking crates.io crate relp-num 0.1.8
[INFO] tweaked toml for crates.io crate relp-num 0.1.8 written to /workspace/builds/worker-107/source/Cargo.toml
[INFO] crate crates.io crate relp-num 0.1.8 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]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded crossbeam-utils v0.8.4
[INFO] [stderr]   Downloaded plotters-svg v0.3.0
[INFO] [stderr]   Downloaded half v1.7.1
[INFO] [stderr]   Downloaded crossbeam-deque v0.8.0
[INFO] [stderr]   Downloaded criterion v0.3.4
[INFO] [stderr]   Downloaded libc v0.2.95
[INFO] [stderr]   Downloaded criterion-plot v0.4.3
[INFO] [stderr]   Downloaded cast v0.2.6
[INFO] [stderr]   Downloaded cc v1.0.68
[INFO] [stderr]   Downloaded itertools v0.9.0
[INFO] [stderr]   Downloaded bstr v0.2.16
[INFO] [stderr]   Downloaded itertools v0.10.0
[INFO] [stderr]   Downloaded serde_cbor v0.11.1
[INFO] [stderr]   Downloaded crossbeam-epoch v0.9.4
[INFO] [stderr]   Downloaded index-utils v1.0.0
[INFO] [stderr]   Downloaded gcd v2.0.1
[INFO] [stderr]   Downloaded syn v1.0.72
[INFO] [stderr]   Downloaded proc-macro2 v1.0.27
[INFO] [stderr]   Downloaded iai v0.1.1
[INFO] [stderr]   Downloaded plotters-backend v0.3.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-107/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-107/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] dc6d1fe01af2821958a0a09f6bcd7bd36cd2332b95c200152dd1a8af18b12544
[INFO] running `Command { std: "docker" "start" "-a" "dc6d1fe01af2821958a0a09f6bcd7bd36cd2332b95c200152dd1a8af18b12544", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dc6d1fe01af2821958a0a09f6bcd7bd36cd2332b95c200152dd1a8af18b12544", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dc6d1fe01af2821958a0a09f6bcd7bd36cd2332b95c200152dd1a8af18b12544", kill_on_drop: false }`
[INFO] [stdout] dc6d1fe01af2821958a0a09f6bcd7bd36cd2332b95c200152dd1a8af18b12544
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-107/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-107/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" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1ef4b12e8ec146e65c6150ae2f5b93495ab094e62a20db9c7c546c4eff349ca7
[INFO] running `Command { std: "docker" "start" "-a" "1ef4b12e8ec146e65c6150ae2f5b93495ab094e62a20db9c7c546c4eff349ca7", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling ucd-trie v0.1.3
[INFO] [stderr]    Compiling serde v1.0.126
[INFO] [stderr]    Compiling libc v0.2.95
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling memchr v2.4.0
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]    Compiling cc v1.0.68
[INFO] [stderr]     Checking plotters-backend v0.3.0
[INFO] [stderr]     Checking regex-syntax v0.6.25
[INFO] [stderr]     Checking half v1.7.1
[INFO] [stderr]     Checking oorandom v11.1.3
[INFO] [stderr]     Checking index-utils v1.0.0
[INFO] [stderr]     Checking smallvec v1.6.1
[INFO] [stderr]     Checking gcd v2.0.1
[INFO] [stderr]     Checking iai v0.1.1
[INFO] [stderr]    Compiling crossbeam-utils v0.8.4
[INFO] [stderr]    Compiling memoffset v0.6.4
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]     Checking regex-automata v0.1.9
[INFO] [stderr]     Checking walkdir v2.3.2
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]    Compiling rayon v1.5.1
[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:75:41
[INFO] [stdout]    |
[INFO] [stdout] 75 | #![cfg_attr(feature = "specialization", feature(specialization))]
[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 `smallvec` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[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/index-utils-1.0.0/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(drain_filter)]
[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/index-utils-1.0.0/src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(is_sorted)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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" "1ef4b12e8ec146e65c6150ae2f5b93495ab094e62a20db9c7c546c4eff349ca7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1ef4b12e8ec146e65c6150ae2f5b93495ab094e62a20db9c7c546c4eff349ca7", kill_on_drop: false }`
[INFO] [stdout] 1ef4b12e8ec146e65c6150ae2f5b93495ab094e62a20db9c7c546c4eff349ca7
