[INFO] fetching crate descent_ipopt 0.5.0...
[INFO] checking descent_ipopt-0.5.0 against 1.95.0 for pr-155915
[INFO] extracting crate descent_ipopt 0.5.0 into /workspace/builds/worker-7-tc1/source
[INFO] started tweaking crates.io crate descent_ipopt 0.5.0
[INFO] removed 0 missing examples
[INFO] finished tweaking crates.io crate descent_ipopt 0.5.0
[INFO] tweaked toml for crates.io crate descent_ipopt 0.5.0 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate descent_ipopt 0.5.0 on toolchain 1.95.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate descent_ipopt 0.5.0 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" "+1.95.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded descent v0.5.0
[INFO] [stderr]   Downloaded descent_macro v0.5.0
[INFO] [stderr]   Downloaded libc v0.2.84
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b3da881138508fb93684b8cb11570bc0b6f552d2f95f3938ce1c5c88c23cb7da
[INFO] running `Command { std: "docker" "start" "-a" "b3da881138508fb93684b8cb11570bc0b6f552d2f95f3938ce1c5c88c23cb7da", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b3da881138508fb93684b8cb11570bc0b6f552d2f95f3938ce1c5c88c23cb7da", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b3da881138508fb93684b8cb11570bc0b6f552d2f95f3938ce1c5c88c23cb7da", kill_on_drop: false }`
[INFO] [stdout] b3da881138508fb93684b8cb11570bc0b6f552d2f95f3938ce1c5c88c23cb7da
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1466f6c56c1d4b5af784aad5432bd040ab8fb20518e7a162b131a9ed024b61a4
[INFO] running `Command { std: "docker" "start" "-a" "1466f6c56c1d4b5af784aad5432bd040ab8fb20518e7a162b131a9ed024b61a4", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]    Compiling libc v0.2.84
[INFO] [stderr]    Compiling descent_macro v0.5.0
[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-1949cf8c6b5b557f/descent_macro-0.5.0/src/lib.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(proc_macro_hygiene)]
[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 `descent_macro` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "1466f6c56c1d4b5af784aad5432bd040ab8fb20518e7a162b131a9ed024b61a4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1466f6c56c1d4b5af784aad5432bd040ab8fb20518e7a162b131a9ed024b61a4", kill_on_drop: false }`
[INFO] [stdout] 1466f6c56c1d4b5af784aad5432bd040ab8fb20518e7a162b131a9ed024b61a4