[INFO] fetching crate iso-macro 0.0.2...
[INFO] testing iso-macro-0.0.2 against beta-2021-09-08 for beta-1.56-1
[INFO] extracting crate iso-macro 0.0.2 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate iso-macro 0.0.2 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate iso-macro 0.0.2
[INFO] finished tweaking crates.io crate iso-macro 0.0.2
[INFO] tweaked toml for crates.io crate iso-macro 0.0.2 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 86d0b4c2941801b87b899bd1a4bc73b4bdebd9d776b67d8baf3971125110d1a8
[INFO] running `Command { std: "docker" "start" "-a" "86d0b4c2941801b87b899bd1a4bc73b4bdebd9d776b67d8baf3971125110d1a8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "86d0b4c2941801b87b899bd1a4bc73b4bdebd9d776b67d8baf3971125110d1a8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "86d0b4c2941801b87b899bd1a4bc73b4bdebd9d776b67d8baf3971125110d1a8", kill_on_drop: false }`
[INFO] [stdout] 86d0b4c2941801b87b899bd1a4bc73b4bdebd9d776b67d8baf3971125110d1a8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f817f2c019e3327650faf823c316b6102e09d5d7e1990c182ffa32c9f567764b
[INFO] running `Command { std: "docker" "start" "-a" "f817f2c019e3327650faf823c316b6102e09d5d7e1990c182ffa32c9f567764b", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling iso-macro v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:37:1
[INFO] [stdout]    |
[INFO] [stdout] 37 | #![feature(proc_macro_diagnostic)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `iso-macro` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "f817f2c019e3327650faf823c316b6102e09d5d7e1990c182ffa32c9f567764b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f817f2c019e3327650faf823c316b6102e09d5d7e1990c182ffa32c9f567764b", kill_on_drop: false }`
[INFO] [stdout] f817f2c019e3327650faf823c316b6102e09d5d7e1990c182ffa32c9f567764b