[INFO] fetching crate lain 0.5.5...
[INFO] checking lain-0.5.5 against 1.55.0 for beta-1.56-3
[INFO] extracting crate lain 0.5.5 into /workspace/builds/worker-56/source
[INFO] validating manifest of crates.io crate lain 0.5.5 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 lain 0.5.5
[INFO] finished tweaking crates.io crate lain 0.5.5
[INFO] tweaked toml for crates.io crate lain 0.5.5 written to /workspace/builds/worker-56/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] 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-56/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-56/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] dc1642290efea0ae4034f9e433dedaae070da64407199cb22f1b54bca15b24cc
[INFO] running `Command { std: "docker" "start" "-a" "dc1642290efea0ae4034f9e433dedaae070da64407199cb22f1b54bca15b24cc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dc1642290efea0ae4034f9e433dedaae070da64407199cb22f1b54bca15b24cc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dc1642290efea0ae4034f9e433dedaae070da64407199cb22f1b54bca15b24cc", kill_on_drop: false }`
[INFO] [stdout] dc1642290efea0ae4034f9e433dedaae070da64407199cb22f1b54bca15b24cc
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-56/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-56/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] 31eefcaba6f645069b3c85bed354db0746e9a531b990a5c4db5c64828acf2e40
[INFO] running `Command { std: "docker" "start" "-a" "31eefcaba6f645069b3c85bed354db0746e9a531b990a5c4db5c64828acf2e40", kill_on_drop: false }`
[INFO] [stderr]    Compiling ucd-trie v0.1.3
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]    Compiling byteorder v1.4.3
[INFO] [stderr]    Compiling paste v1.0.5
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.2.6
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-rational v0.2.4
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking rand_pcg v0.2.1
[INFO] [stderr]    Compiling pest v2.1.3
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling semver-parser v0.10.2
[INFO] [stderr]    Compiling semver v0.11.0
[INFO] [stderr]    Compiling rustc_version v0.3.3
[INFO] [stderr]    Compiling field-offset v0.3.4
[INFO] [stderr]     Checking num v0.2.1
[INFO] [stderr]    Compiling lain_derive v0.5.5
[INFO] [stderr]     Checking lain v0.5.5 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> src/lib.rs:101:1
[INFO] [stdout]     |
[INFO] [stdout] 101 | #![feature(specialization)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> src/lib.rs:102:1
[INFO] [stdout]     |
[INFO] [stdout] 102 | #![feature(min_const_generics)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]     |
[INFO] [stdout]     = help: the feature `min_const_generics` has been stable since 1.51.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> src/lib.rs:101:1
[INFO] [stdout]     |
[INFO] [stdout] 101 | #![feature(specialization)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> src/lib.rs:102:1
[INFO] [stdout]     |
[INFO] [stdout] 102 | #![feature(min_const_generics)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]     |
[INFO] [stdout]     = help: the feature `min_const_generics` has been stable since 1.51.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]    --> src/lib.rs:101:12
[INFO] [stdout]     |
[INFO] [stdout] 101 | #![feature(specialization)]
[INFO] [stdout]     |            ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]     = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]     = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]    --> src/lib.rs:101:12
[INFO] [stdout]     |
[INFO] [stdout] 101 | #![feature(specialization)]
[INFO] [stdout]     |            ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]     = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]     = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lain` due to 3 previous errors; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "31eefcaba6f645069b3c85bed354db0746e9a531b990a5c4db5c64828acf2e40", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "31eefcaba6f645069b3c85bed354db0746e9a531b990a5c4db5c64828acf2e40", kill_on_drop: false }`
[INFO] [stdout] 31eefcaba6f645069b3c85bed354db0746e9a531b990a5c4db5c64828acf2e40
