[INFO] fetching crate unmp-link 0.7.0...
[INFO] testing unmp-link-0.7.0 against beta-2025-09-21 for beta-1.91-3
[INFO] extracting crate unmp-link 0.7.0 into /workspace/builds/worker-5-tc2/source
[INFO] started tweaking crates.io crate unmp-link 0.7.0
[INFO] finished tweaking crates.io crate unmp-link 0.7.0
[INFO] tweaked toml for crates.io crate unmp-link 0.7.0 written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate unmp-link 0.7.0 on toolchain beta-2025-09-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-09-21" "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-2025-09-21" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 8 packages to latest compatible versions
[INFO] [stderr]       Adding fixed-queue v0.3.11 (available: v0.5.1)
[INFO] [stderr]       Adding futures-intrusive v0.4.2 (available: v0.5.0)
[INFO] [stderr]       Adding spin v0.9.8 (available: v0.10.0)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-09-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 52ea2bc43882fa80a1611453ed93de183759ef9c043f30bf6d29c1cda0101191
[INFO] running `Command { std: "docker" "start" "-a" "52ea2bc43882fa80a1611453ed93de183759ef9c043f30bf6d29c1cda0101191", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "52ea2bc43882fa80a1611453ed93de183759ef9c043f30bf6d29c1cda0101191", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "52ea2bc43882fa80a1611453ed93de183759ef9c043f30bf6d29c1cda0101191", kill_on_drop: false }`
[INFO] [stdout] 52ea2bc43882fa80a1611453ed93de183759ef9c043f30bf6d29c1cda0101191
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d5b337fb7172c7da3e950c877ade980b507bbb13e18f2234586d5160f28e804b
[INFO] running `Command { std: "docker" "start" "-a" "d5b337fb7172c7da3e950c877ade980b507bbb13e18f2234586d5160f28e804b", kill_on_drop: false }`
[INFO] [stderr]    Compiling futures-core v0.3.31
[INFO] [stderr]    Compiling fixed-queue v0.3.11
[INFO] [stderr]    Compiling spin v0.9.8
[INFO] [stderr]    Compiling futures-intrusive v0.4.2
[INFO] [stderr]    Compiling unmp-link v0.7.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(const_btree_new)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `const_btree_new` has been partially stabilized since 1.66.0 and is succeeded by the feature `const_btree_len`
[INFO] [stdout]  --> src/lib.rs:6:12
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(const_btree_new)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] help: if you are using features which are still unstable, change to using `const_btree_len`
[INFO] [stdout]   |
[INFO] [stdout] 6 - #![feature(const_btree_new)]
[INFO] [stdout] 6 + #![feature(const_btree_len)]
[INFO] [stdout]   |
[INFO] [stdout] help: if you are using features which are now stable, remove this line
[INFO] [stdout]   |
[INFO] [stdout] 6 - #![feature(const_btree_new)]
[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 `unmp-link` (lib) due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "d5b337fb7172c7da3e950c877ade980b507bbb13e18f2234586d5160f28e804b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d5b337fb7172c7da3e950c877ade980b507bbb13e18f2234586d5160f28e804b", kill_on_drop: false }`
[INFO] [stdout] d5b337fb7172c7da3e950c877ade980b507bbb13e18f2234586d5160f28e804b