[INFO] fetching crate lager 0.2.0...
[INFO] testing lager-0.2.0 against 1.90.0 for beta-1.91-3
[INFO] extracting crate lager 0.2.0 into /workspace/builds/worker-6-tc1/source
[INFO] started tweaking crates.io crate lager 0.2.0
[INFO] finished tweaking crates.io crate lager 0.2.0
[INFO] tweaked toml for crates.io crate lager 0.2.0 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate lager 0.2.0 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate lager 0.2.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded memoffset v0.6.4
[INFO] [stderr]   Downloaded plotters-svg v0.3.1
[INFO] [stderr]   Downloaded criterion-plot v0.4.4
[INFO] [stderr]   Downloaded walkdir v2.3.2
[INFO] [stderr]   Downloaded semver v1.0.4
[INFO] [stderr]   Downloaded proc-macro2 v1.0.32
[INFO] [stderr]   Downloaded criterion v0.3.5
[INFO] [stderr]   Downloaded serde_derive v1.0.130
[INFO] [stderr]   Downloaded serde v1.0.130
[INFO] [stderr]   Downloaded serde_json v1.0.68
[INFO] [stderr]   Downloaded plotters-backend v0.3.2
[INFO] [stderr]   Downloaded quote v1.0.10
[INFO] [stderr]   Downloaded syn v1.0.81
[INFO] [stderr]   Downloaded libc v0.2.106
[INFO] [stderr]   Downloaded plotters v0.3.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6cd1476613465e991eb645e56d0db206b988aa3f702980bd500e438ace93155a
[INFO] running `Command { std: "docker" "start" "-a" "6cd1476613465e991eb645e56d0db206b988aa3f702980bd500e438ace93155a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6cd1476613465e991eb645e56d0db206b988aa3f702980bd500e438ace93155a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6cd1476613465e991eb645e56d0db206b988aa3f702980bd500e438ace93155a", kill_on_drop: false }`
[INFO] [stdout] 6cd1476613465e991eb645e56d0db206b988aa3f702980bd500e438ace93155a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b5cc1451e032c7b68b60499bae51085274c3f545e09621c49ce0c4e460f93900
[INFO] running `Command { std: "docker" "start" "-a" "b5cc1451e032c7b68b60499bae51085274c3f545e09621c49ce0c4e460f93900", kill_on_drop: false }`
[INFO] [stderr]    Compiling lager v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(generic_const_exprs)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lager` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "b5cc1451e032c7b68b60499bae51085274c3f545e09621c49ce0c4e460f93900", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b5cc1451e032c7b68b60499bae51085274c3f545e09621c49ce0c4e460f93900", kill_on_drop: false }`
[INFO] [stdout] b5cc1451e032c7b68b60499bae51085274c3f545e09621c49ce0c4e460f93900