[INFO] fetching crate taylor 0.0.1...
[INFO] testing taylor-0.0.1 against 1.60.0 for beta-1.61-1
[INFO] extracting crate taylor 0.0.1 into /workspace/builds/worker-101/source
[INFO] validating manifest of crates.io crate taylor 0.0.1 on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate taylor 0.0.1
[INFO] finished tweaking crates.io crate taylor 0.0.1
[INFO] tweaked toml for crates.io crate taylor 0.0.1 written to /workspace/builds/worker-101/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "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 factorial v0.2.1
[INFO] [stderr]   Downloaded math-ast v0.2.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-101/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-101/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0fab21f5afa705c43186471dc55989dd3c9f7f677994cdef1410106020261982
[INFO] running `Command { std: "docker" "start" "-a" "0fab21f5afa705c43186471dc55989dd3c9f7f677994cdef1410106020261982", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0fab21f5afa705c43186471dc55989dd3c9f7f677994cdef1410106020261982", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0fab21f5afa705c43186471dc55989dd3c9f7f677994cdef1410106020261982", kill_on_drop: false }`
[INFO] [stdout] 0fab21f5afa705c43186471dc55989dd3c9f7f677994cdef1410106020261982
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-101/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-101/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2a4a8b82ec8ec635f9195dde4428d99ede47042422940d3346daf9c3656da91e
[INFO] running `Command { std: "docker" "start" "-a" "2a4a8b82ec8ec635f9195dde4428d99ede47042422940d3346daf9c3656da91e", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.3.3
[INFO] [stderr]    Compiling num-rational v0.3.2
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-complex v0.3.1
[INFO] [stderr]    Compiling factorial v0.2.1
[INFO] [stderr]    Compiling num v0.3.1
[INFO] [stderr]    Compiling math-ast v0.2.0
[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/math-ast-0.2.0/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(box_syntax)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `math-ast` due to 2 previous errors
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "2a4a8b82ec8ec635f9195dde4428d99ede47042422940d3346daf9c3656da91e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2a4a8b82ec8ec635f9195dde4428d99ede47042422940d3346daf9c3656da91e", kill_on_drop: false }`
[INFO] [stdout] 2a4a8b82ec8ec635f9195dde4428d99ede47042422940d3346daf9c3656da91e