[INFO] fetching crate remain 0.2.2...
[INFO] testing remain-0.2.2 against 1.60.0 for beta-1.61-1
[INFO] extracting crate remain 0.2.2 into /workspace/builds/worker-88/source
[INFO] validating manifest of crates.io crate remain 0.2.2 on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate remain 0.2.2
[INFO] finished tweaking crates.io crate remain 0.2.2
[INFO] tweaked toml for crates.io crate remain 0.2.2 written to /workspace/builds/worker-88/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d815f14c1a70808138ea3b47451ce0a3a5b3352470b388e1fc97a0712f98d0b2
[INFO] running `Command { std: "docker" "start" "-a" "d815f14c1a70808138ea3b47451ce0a3a5b3352470b388e1fc97a0712f98d0b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d815f14c1a70808138ea3b47451ce0a3a5b3352470b388e1fc97a0712f98d0b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d815f14c1a70808138ea3b47451ce0a3a5b3352470b388e1fc97a0712f98d0b2", kill_on_drop: false }`
[INFO] [stdout] d815f14c1a70808138ea3b47451ce0a3a5b3352470b388e1fc97a0712f98d0b2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 518d8db08bfdecea2161e16abad55a3b4469f00ac3c3f731ec90eea381d07b6c
[INFO] running `Command { std: "docker" "start" "-a" "518d8db08bfdecea2161e16abad55a3b4469f00ac3c3f731ec90eea381d07b6c", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.91
[INFO] [stderr]    Compiling remain v0.2.2 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 8.44s
[INFO] running `Command { std: "docker" "inspect" "518d8db08bfdecea2161e16abad55a3b4469f00ac3c3f731ec90eea381d07b6c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "518d8db08bfdecea2161e16abad55a3b4469f00ac3c3f731ec90eea381d07b6c", kill_on_drop: false }`
[INFO] [stdout] 518d8db08bfdecea2161e16abad55a3b4469f00ac3c3f731ec90eea381d07b6c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6188dc3405f4081cd5f39ba1f1760bec92a17c0599f7040eca09e70ddc67ea4e
[INFO] running `Command { std: "docker" "start" "-a" "6188dc3405f4081cd5f39ba1f1760bec92a17c0599f7040eca09e70ddc67ea4e", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v1.0.136
[INFO] [stderr]    Compiling serde_json v1.0.79
[INFO] [stderr]    Compiling rustversion v1.0.6
[INFO] [stderr]    Compiling trybuild v1.0.59
[INFO] [stderr]    Compiling dissimilar v1.0.3
[INFO] [stderr]    Compiling serde_derive v1.0.136
[INFO] [stderr]    Compiling toml v0.5.8
[INFO] [stderr]    Compiling remain v0.2.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> tests/unstable.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(proc_macro_hygiene, stmt_expr_attributes)]
[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 `remain` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "6188dc3405f4081cd5f39ba1f1760bec92a17c0599f7040eca09e70ddc67ea4e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6188dc3405f4081cd5f39ba1f1760bec92a17c0599f7040eca09e70ddc67ea4e", kill_on_drop: false }`
[INFO] [stdout] 6188dc3405f4081cd5f39ba1f1760bec92a17c0599f7040eca09e70ddc67ea4e