[INFO] fetching crate mcproto-rs 0.2.0...
[INFO] testing mcproto-rs-0.2.0 against 1.90.0 for beta-1.91-3
[INFO] extracting crate mcproto-rs 0.2.0 into /workspace/builds/worker-6-tc1/source
[INFO] started tweaking crates.io crate mcproto-rs 0.2.0
[INFO] finished tweaking crates.io crate mcproto-rs 0.2.0
[INFO] tweaked toml for crates.io crate mcproto-rs 0.2.0 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate mcproto-rs 0.2.0 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "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" "+1.90.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]      Locking 27 packages to latest compatible versions
[INFO] [stderr]       Adding base64 v0.12.3 (available: v0.22.1)
[INFO] [stderr]       Adding rand v0.7.3 (available: v0.9.2)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "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-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 52ba9182527983ff40fd631b256a50ba1a319eca9ad7453643565f0202715f52
[INFO] running `Command { std: "docker" "start" "-a" "52ba9182527983ff40fd631b256a50ba1a319eca9ad7453643565f0202715f52", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "52ba9182527983ff40fd631b256a50ba1a319eca9ad7453643565f0202715f52", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "52ba9182527983ff40fd631b256a50ba1a319eca9ad7453643565f0202715f52", kill_on_drop: false }`
[INFO] [stdout] 52ba9182527983ff40fd631b256a50ba1a319eca9ad7453643565f0202715f52
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4d104690d07ff4c4247f0d841321a9dd2d7dcea512b0af4e7aeadd40536a0d5f
[INFO] running `Command { std: "docker" "start" "-a" "4d104690d07ff4c4247f0d841321a9dd2d7dcea512b0af4e7aeadd40536a0d5f", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.176
[INFO] [stderr]    Compiling serde_core v1.0.228
[INFO] [stderr]    Compiling serde v1.0.228
[INFO] [stderr]    Compiling serde_json v1.0.145
[INFO] [stderr]    Compiling memchr v2.7.6
[INFO] [stderr]    Compiling base64 v0.12.3
[INFO] [stderr]    Compiling syn v2.0.106
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling serde_derive v1.0.228
[INFO] [stderr]    Compiling mcproto-rs v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:32
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(feature = "bench", feature(test))]
[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 `mcproto-rs` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "4d104690d07ff4c4247f0d841321a9dd2d7dcea512b0af4e7aeadd40536a0d5f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d104690d07ff4c4247f0d841321a9dd2d7dcea512b0af4e7aeadd40536a0d5f", kill_on_drop: false }`
[INFO] [stdout] 4d104690d07ff4c4247f0d841321a9dd2d7dcea512b0af4e7aeadd40536a0d5f