[INFO] fetching crate unwrap_helpers 0.3.0...
[INFO] checking unwrap_helpers-0.3.0 against 1.95.0 for pr-155915
[INFO] extracting crate unwrap_helpers 0.3.0 into /workspace/builds/worker-4-tc1/source
[INFO] started tweaking crates.io crate unwrap_helpers 0.3.0
[INFO] finished tweaking crates.io crate unwrap_helpers 0.3.0
[INFO] tweaked toml for crates.io crate unwrap_helpers 0.3.0 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate unwrap_helpers 0.3.0 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] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 6 packages to latest compatible versions
[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]  Downloading crates ...
[INFO] [stderr]   Downloaded loop_unwrap v0.2.0
[INFO] [stderr]   Downloaded unwrap_helpers_proc_macros v0.1.1
[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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9f859adde0791810b027a14287ba7264684dea5fa92d8c62e8fbf13974d41aee
[INFO] running `Command { std: "docker" "start" "-a" "9f859adde0791810b027a14287ba7264684dea5fa92d8c62e8fbf13974d41aee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9f859adde0791810b027a14287ba7264684dea5fa92d8c62e8fbf13974d41aee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f859adde0791810b027a14287ba7264684dea5fa92d8c62e8fbf13974d41aee", kill_on_drop: false }`
[INFO] [stdout] 9f859adde0791810b027a14287ba7264684dea5fa92d8c62e8fbf13974d41aee
[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=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] 213eacb3910ffc29c0ad5309529bdbb7823eb806108f508c98e003c152a20cdb
[INFO] running `Command { std: "docker" "start" "-a" "213eacb3910ffc29c0ad5309529bdbb7823eb806108f508c98e003c152a20cdb", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.106
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]     Checking loop_unwrap v0.2.0
[INFO] [stderr]    Compiling quote v1.0.45
[INFO] [stderr]    Compiling unwrap_helpers_proc_macros v0.1.1
[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/unwrap_helpers_proc_macros-0.1.1/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(box_patterns)]
[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 `unwrap_helpers_proc_macros` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "213eacb3910ffc29c0ad5309529bdbb7823eb806108f508c98e003c152a20cdb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "213eacb3910ffc29c0ad5309529bdbb7823eb806108f508c98e003c152a20cdb", kill_on_drop: false }`
[INFO] [stdout] 213eacb3910ffc29c0ad5309529bdbb7823eb806108f508c98e003c152a20cdb
