[INFO] fetching crate mantle 0.2.1...
[INFO] checking mantle-0.2.1 against 1.55.0 for beta-1.56-3
[INFO] extracting crate mantle 0.2.1 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate mantle 0.2.1 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 mantle 0.2.1
[INFO] finished tweaking crates.io crate mantle 0.2.1
[INFO] tweaked toml for crates.io crate mantle 0.2.1 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] 7c4f8fb3cc34e2e223e75ee33b7be55c8cf7c249568e7403e8cea5a467ecbffe
[INFO] running `Command { std: "docker" "start" "-a" "7c4f8fb3cc34e2e223e75ee33b7be55c8cf7c249568e7403e8cea5a467ecbffe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7c4f8fb3cc34e2e223e75ee33b7be55c8cf7c249568e7403e8cea5a467ecbffe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7c4f8fb3cc34e2e223e75ee33b7be55c8cf7c249568e7403e8cea5a467ecbffe", kill_on_drop: false }`
[INFO] [stdout] 7c4f8fb3cc34e2e223e75ee33b7be55c8cf7c249568e7403e8cea5a467ecbffe
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] bd6c64e0da4460c24a7a00dc70160646d1b1b4e5f4c698ef62806737e21a53e6
[INFO] running `Command { std: "docker" "start" "-a" "bd6c64e0da4460c24a7a00dc70160646d1b1b4e5f4c698ef62806737e21a53e6", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.80
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling crunchy v0.2.2
[INFO] [stderr]     Checking hex v0.4.3
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]     Checking gimli v0.25.0
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]     Checking rustc-demangle v0.1.21
[INFO] [stderr]     Checking half v1.8.0
[INFO] [stderr]     Checking hex v0.3.2
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]    Compiling backtrace v0.3.61
[INFO] [stderr]     Checking anyhow v1.0.44
[INFO] [stderr]     Checking object v0.26.2
[INFO] [stderr]    Compiling tiny-keccak v1.5.0
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling proc-quote-impl v0.2.2
[INFO] [stderr]     Checking addr2line v0.16.0
[INFO] [stderr]    Compiling synstructure v0.12.6
[INFO] [stderr]    Compiling thiserror-impl v1.0.30
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]    Compiling proc-quote v0.2.2
[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]     Checking thiserror v1.0.30
[INFO] [stderr]    Compiling derive_more v0.15.0
[INFO] [stderr]    Compiling mantle-macros v0.2.1
[INFO] [stderr]    Compiling default-env v0.1.1
[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/mantle-macros-0.2.1/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(proc_macro_diagnostic, type_ascription)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `mantle-macros` due to 2 previous errors
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[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" "bd6c64e0da4460c24a7a00dc70160646d1b1b4e5f4c698ef62806737e21a53e6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bd6c64e0da4460c24a7a00dc70160646d1b1b4e5f4c698ef62806737e21a53e6", kill_on_drop: false }`
[INFO] [stdout] bd6c64e0da4460c24a7a00dc70160646d1b1b4e5f4c698ef62806737e21a53e6
