[INFO] fetching crate microamp 0.1.0-alpha.6...
[INFO] testing microamp-0.1.0-alpha.6 against 1.54.0 for beta-1.55-1
[INFO] extracting crate microamp 0.1.0-alpha.6 into /workspace/builds/worker-40/source
[INFO] validating manifest of crates.io crate microamp 0.1.0-alpha.6 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate microamp 0.1.0-alpha.6
[INFO] finished tweaking crates.io crate microamp 0.1.0-alpha.6
[INFO] tweaked toml for crates.io crate microamp 0.1.0-alpha.6 written to /workspace/builds/worker-40/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-40/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-40/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b9f46e0a2d35e6a0c7ae6eab6aeafdc8a78a459d34cdb5ebb7204f607346c824
[INFO] running `Command { std: "docker" "start" "-a" "b9f46e0a2d35e6a0c7ae6eab6aeafdc8a78a459d34cdb5ebb7204f607346c824", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b9f46e0a2d35e6a0c7ae6eab6aeafdc8a78a459d34cdb5ebb7204f607346c824", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b9f46e0a2d35e6a0c7ae6eab6aeafdc8a78a459d34cdb5ebb7204f607346c824", kill_on_drop: false }`
[INFO] [stdout] b9f46e0a2d35e6a0c7ae6eab6aeafdc8a78a459d34cdb5ebb7204f607346c824
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-40/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-40/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] aac37d211fba14e25aa4c1d78c09a6bb06d29f9b53d0d0858543406edc16c283
[INFO] running `Command { std: "docker" "start" "-a" "aac37d211fba14e25aa4c1d78c09a6bb06d29f9b53d0d0858543406edc16c283", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.28
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling microamp-macros v0.1.0-alpha.5
[INFO] [stderr]    Compiling microamp v0.1.0-alpha.6 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(external_doc)]
[INFO] [stdout]   |            ^^^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: use #[doc = include_str!("filename")] instead, which handles macro invocations
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(external_doc)]
[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:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(auto_traits)]
[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:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(negative_impls)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unknown `doc` attribute `include`
[INFO] [stdout]  --> src/lib.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![doc(include = "../README.md")]
[INFO] [stdout]   | -------^^^^^^^^^^^^^^^^^^^^^^^^-- help: use `doc = include_str!` instead: `#![doc = include_str!("../README.md")]`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(invalid_doc_attributes)]` on by default
[INFO] [stdout]   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]   = note: for more information, see issue #82730 <https://github.com/rust-lang/rust/issues/82730>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `microamp`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "aac37d211fba14e25aa4c1d78c09a6bb06d29f9b53d0d0858543406edc16c283", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aac37d211fba14e25aa4c1d78c09a6bb06d29f9b53d0d0858543406edc16c283", kill_on_drop: false }`
[INFO] [stdout] aac37d211fba14e25aa4c1d78c09a6bb06d29f9b53d0d0858543406edc16c283
