[INFO] fetching crate tube 0.0.2...
[INFO] testing tube-0.0.2 against beta-2026-04-21 for beta-1.96-2
[INFO] extracting crate tube 0.0.2 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate tube 0.0.2
[INFO] finished tweaking crates.io crate tube 0.0.2
[INFO] tweaked toml for crates.io crate tube 0.0.2 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate tube 0.0.2 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] crate crates.io crate tube 0.0.2 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" "+beta-2026-04-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 7c40f4f51a16518e766b79d489c1c3ec876eb5a5533a76fa475121c8fe1ec159
[INFO] running `Command { std: "docker" "start" "-a" "7c40f4f51a16518e766b79d489c1c3ec876eb5a5533a76fa475121c8fe1ec159", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7c40f4f51a16518e766b79d489c1c3ec876eb5a5533a76fa475121c8fe1ec159", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7c40f4f51a16518e766b79d489c1c3ec876eb5a5533a76fa475121c8fe1ec159", kill_on_drop: false }`
[INFO] [stdout] 7c40f4f51a16518e766b79d489c1c3ec876eb5a5533a76fa475121c8fe1ec159
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] c571603e40c467462baacdd7a5a0a87b8fdc77ca9fbf28f86c1dd3e6a4f0ac1c
[INFO] running `Command { std: "docker" "start" "-a" "c571603e40c467462baacdd7a5a0a87b8fdc77ca9fbf28f86c1dd3e6a4f0ac1c", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling proc-macro2 v1.0.40
[INFO] [stderr]    Compiling unicode-ident v1.0.1
[INFO] [stderr]    Compiling quote v1.0.20
[INFO] [stderr]    Compiling syn v1.0.98
[INFO] [stderr]    Compiling pin-project-lite v0.2.9
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling futures-core v0.3.21
[INFO] [stderr]    Compiling itoa v1.0.2
[INFO] [stderr]    Compiling futures-sink v0.3.21
[INFO] [stderr]    Compiling futures-channel v0.3.21
[INFO] [stderr]    Compiling futures-task v0.3.21
[INFO] [stderr]    Compiling once_cell v1.12.0
[INFO] [stderr]    Compiling bytes v1.1.0
[INFO] [stderr]    Compiling futures-util v0.3.21
[INFO] [stderr]    Compiling futures-io v0.3.21
[INFO] [stderr]    Compiling slab v0.4.6
[INFO] [stderr]    Compiling pin-utils v0.1.0
[INFO] [stderr]    Compiling indexmap v1.9.1
[INFO] [stderr]    Compiling tracing-core v0.1.28
[INFO] [stderr]    Compiling fnv v1.0.7
[INFO] [stderr]    Compiling hashbrown v0.12.1
[INFO] [stderr]    Compiling httparse v1.7.1
[INFO] [stderr]    Compiling serde v1.0.137
[INFO] [stderr]    Compiling num_threads v0.1.6
[INFO] [stderr]    Compiling try-lock v0.2.3
[INFO] [stderr]    Compiling http v0.2.8
[INFO] [stderr]    Compiling serde_json v1.0.81
[INFO] [stderr]    Compiling time-macros v0.2.4
[INFO] [stderr]    Compiling want v0.3.0
[INFO] [stderr]    Compiling ryu v1.0.10
[INFO] [stderr]    Compiling httpdate v1.0.2
[INFO] [stderr]    Compiling tower-service v0.3.2
[INFO] [stderr]    Compiling tracing v0.1.35
[INFO] [stderr]    Compiling num_cpus v1.13.1
[INFO] [stderr]    Compiling mio v0.8.4
[INFO] [stderr]    Compiling socket2 v0.4.4
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling colored v2.0.0
[INFO] [stderr]    Compiling http-body v0.4.5
[INFO] [stderr]    Compiling time v0.3.11
[INFO] [stderr]    Compiling simple_logger v2.2.0
[INFO] [stderr]    Compiling futures-macro v0.3.21
[INFO] [stderr]    Compiling tokio-macros v1.8.0
[INFO] [stderr]    Compiling tokio v1.19.2
[INFO] [stderr]    Compiling futures-executor v0.3.21
[INFO] [stderr]    Compiling futures v0.3.21
[INFO] [stderr]    Compiling tokio-util v0.7.3
[INFO] [stderr]    Compiling h2 v0.3.13
[INFO] [stderr]    Compiling hyper v0.14.19
[INFO] [stderr]    Compiling tube v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(assert_matches)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `assert_matches` has been stable since 1.95.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(assert_matches)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `tube` (lib) due to 1 previous error; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "c571603e40c467462baacdd7a5a0a87b8fdc77ca9fbf28f86c1dd3e6a4f0ac1c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c571603e40c467462baacdd7a5a0a87b8fdc77ca9fbf28f86c1dd3e6a4f0ac1c", kill_on_drop: false }`
[INFO] [stdout] c571603e40c467462baacdd7a5a0a87b8fdc77ca9fbf28f86c1dd3e6a4f0ac1c
