[INFO] fetching crate tokio-cache 0.2.0-alpha.1...
[INFO] testing tokio-cache-0.2.0-alpha.1 against beta-2026-04-21 for beta-1.96-2
[INFO] extracting crate tokio-cache 0.2.0-alpha.1 into /workspace/builds/worker-4-tc2/source
[INFO] started tweaking crates.io crate tokio-cache 0.2.0-alpha.1
[INFO] finished tweaking crates.io crate tokio-cache 0.2.0-alpha.1
[INFO] tweaked toml for crates.io crate tokio-cache 0.2.0-alpha.1 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate tokio-cache 0.2.0-alpha.1 on toolchain beta-2026-04-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "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" "+beta-2026-04-21" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 79 packages to latest compatible versions
[INFO] [stderr]       Adding arc-swap v0.4.8 (available: v1.9.1)
[INFO] [stderr]       Adding criterion v0.3.6 (available: v0.8.2)
[INFO] [stderr]       Adding im v13.0.0 (available: v15.1.0)
[INFO] [stderr]       Adding tokio v0.2.25 (available: v1.52.1)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "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-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "+beta-2026-04-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9f38897630c6113d6cc187c870d26ed9ec9f4988d75a8ec6cbb3c91605cdee07
[INFO] running `Command { std: "docker" "start" "-a" "9f38897630c6113d6cc187c870d26ed9ec9f4988d75a8ec6cbb3c91605cdee07", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9f38897630c6113d6cc187c870d26ed9ec9f4988d75a8ec6cbb3c91605cdee07", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f38897630c6113d6cc187c870d26ed9ec9f4988d75a8ec6cbb3c91605cdee07", kill_on_drop: false }`
[INFO] [stdout] 9f38897630c6113d6cc187c870d26ed9ec9f4988d75a8ec6cbb3c91605cdee07
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 69260e4b49bb57483831cadcc972df6f13d2213ccaa6e1d7a2a2f0e1aa6a6d1b
[INFO] running `Command { std: "docker" "start" "-a" "69260e4b49bb57483831cadcc972df6f13d2213ccaa6e1d7a2a2f0e1aa6a6d1b", kill_on_drop: false }`
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling arc-swap v0.4.8
[INFO] [stderr]    Compiling sized-chunks v0.3.1
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling im v13.0.0
[INFO] [stderr]    Compiling tokio-sync v0.2.0-alpha.6
[INFO] [stderr]    Compiling tokio-cache v0.2.0-alpha.1 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.40s
[INFO] running `Command { std: "docker" "inspect" "69260e4b49bb57483831cadcc972df6f13d2213ccaa6e1d7a2a2f0e1aa6a6d1b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "69260e4b49bb57483831cadcc972df6f13d2213ccaa6e1d7a2a2f0e1aa6a6d1b", kill_on_drop: false }`
[INFO] [stdout] 69260e4b49bb57483831cadcc972df6f13d2213ccaa6e1d7a2a2f0e1aa6a6d1b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d701995f0cb7b55c7fca7c73f075a8906a4557b1b32a3735d0c9550dd1d37260
[INFO] running `Command { std: "docker" "start" "-a" "d701995f0cb7b55c7fca7c73f075a8906a4557b1b32a3735d0c9550dd1d37260", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde_core v1.0.228
[INFO] [stderr]    Compiling serde v1.0.228
[INFO] [stderr]    Compiling libc v0.2.186
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling csv-core v0.1.13
[INFO] [stderr]    Compiling syn v2.0.117
[INFO] [stderr]    Compiling criterion-plot v0.4.5
[INFO] [stderr]    Compiling pin-project-lite v0.1.12
[INFO] [stderr]    Compiling bytes v0.5.6
[INFO] [stderr]    Compiling clap v2.34.0
[INFO] [stderr]    Compiling tokio v0.2.25
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling serde_json v1.0.149
[INFO] [stderr]    Compiling csv v1.4.0
[INFO] [stderr]    Compiling serde_cbor v0.11.2
[INFO] [stderr]    Compiling tinytemplate v1.2.1
[INFO] [stderr]    Compiling serde_derive v1.0.228
[INFO] [stderr]    Compiling criterion v0.3.6
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/criterion-0.3.6/src/lib.rs:20:40
[INFO] [stdout]    |
[INFO] [stdout] 20 | #![cfg_attr(feature = "real_blackbox", 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 `criterion` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "d701995f0cb7b55c7fca7c73f075a8906a4557b1b32a3735d0c9550dd1d37260", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d701995f0cb7b55c7fca7c73f075a8906a4557b1b32a3735d0c9550dd1d37260", kill_on_drop: false }`
[INFO] [stdout] d701995f0cb7b55c7fca7c73f075a8906a4557b1b32a3735d0c9550dd1d37260
