[INFO] fetching crate zerogc-context 0.2.0-alpha.7...
[INFO] testing zerogc-context-0.2.0-alpha.7 against 1.75.0 for beta-1.76-1
[INFO] extracting crate zerogc-context 0.2.0-alpha.7 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate zerogc-context 0.2.0-alpha.7 on toolchain 1.75.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate zerogc-context 0.2.0-alpha.7
[INFO] finished tweaking crates.io crate zerogc-context 0.2.0-alpha.7
[INFO] tweaked toml for crates.io crate zerogc-context 0.2.0-alpha.7 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded proc-macro-kwargs v0.1.5
[INFO] [stderr]   Downloaded zerogc v0.2.0-alpha.7
[INFO] [stderr]   Downloaded zerogc-derive v0.2.0-alpha.6
[INFO] [stderr]   Downloaded proc-macro-kwargs-derive v0.1.5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 62e8e05e9270dc84324d9ce9e3da44a3a32763345b98c82548dfcf24302a3845
[INFO] running `Command { std: "docker" "start" "-a" "62e8e05e9270dc84324d9ce9e3da44a3a32763345b98c82548dfcf24302a3845", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "62e8e05e9270dc84324d9ce9e3da44a3a32763345b98c82548dfcf24302a3845", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "62e8e05e9270dc84324d9ce9e3da44a3a32763345b98c82548dfcf24302a3845", kill_on_drop: false }`
[INFO] [stdout] 62e8e05e9270dc84324d9ce9e3da44a3a32763345b98c82548dfcf24302a3845
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 94379039d196f372821b2bc04ebe94bd1ffb409395eb02a008a07ba8e36a0927
[INFO] running `Command { std: "docker" "start" "-a" "94379039d196f372821b2bc04ebe94bd1ffb409395eb02a008a07ba8e36a0927", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.75
[INFO] [stderr]    Compiling unicode-ident v1.0.12
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling ident_case v1.0.1
[INFO] [stderr]    Compiling strsim v0.10.0
[INFO] [stderr]    Compiling fnv v1.0.7
[INFO] [stderr]    Compiling unicode-segmentation v1.10.1
[INFO] [stderr]    Compiling hashbrown v0.12.3
[INFO] [stderr]    Compiling libc v0.2.151
[INFO] [stderr]    Compiling scopeguard v1.2.0
[INFO] [stderr]    Compiling parking_lot_core v0.8.6
[INFO] [stderr]    Compiling either v1.9.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.18
[INFO] [stderr]    Compiling slog v2.7.0
[INFO] [stderr]    Compiling instant v0.1.12
[INFO] [stderr]    Compiling smallvec v1.11.2
[INFO] [stderr]    Compiling bumpalo v3.14.0
[INFO] [stderr]    Compiling itertools v0.10.5
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]    Compiling indexmap v1.9.3
[INFO] [stderr]    Compiling lock_api v0.4.11
[INFO] [stderr]    Compiling quote v1.0.35
[INFO] [stderr]    Compiling syn v2.0.48
[INFO] [stderr]    Compiling parking_lot v0.11.2
[INFO] [stderr]    Compiling inherent v1.0.11
[INFO] [stderr]    Compiling darling_core v0.13.4
[INFO] [stderr]    Compiling proc-macro-kwargs-derive v0.1.5
[INFO] [stderr]    Compiling proc-macro-kwargs v0.1.5
[INFO] [stderr]    Compiling darling_macro v0.13.4
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/proc-macro-kwargs-0.1.5/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(trait_alias)]
[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 `proc-macro-kwargs` (lib) due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "94379039d196f372821b2bc04ebe94bd1ffb409395eb02a008a07ba8e36a0927", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "94379039d196f372821b2bc04ebe94bd1ffb409395eb02a008a07ba8e36a0927", kill_on_drop: false }`
[INFO] [stdout] 94379039d196f372821b2bc04ebe94bd1ffb409395eb02a008a07ba8e36a0927
