[INFO] fetching crate unmp-link-websocket 0.7.1...
[INFO] testing unmp-link-websocket-0.7.1 against 1.95.0 for beta-1.96-2
[INFO] extracting crate unmp-link-websocket 0.7.1 into /workspace/builds/worker-3-tc1/source
[INFO] started tweaking crates.io crate unmp-link-websocket 0.7.1
[INFO] finished tweaking crates.io crate unmp-link-websocket 0.7.1
[INFO] tweaked toml for crates.io crate unmp-link-websocket 0.7.1 written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate unmp-link-websocket 0.7.1 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 157 packages to latest compatible versions
[INFO] [stderr]       Adding async-tungstenite v0.13.1 (available: v0.34.0)
[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 fixed-queue v0.3.11
[INFO] [stderr]   Downloaded unmp-link v0.7.0
[INFO] [stderr]   Downloaded task-stream v0.3.7
[INFO] [stderr]   Downloaded unmp v0.7.3
[INFO] [stderr]   Downloaded crc16 v0.4.0
[INFO] [stderr]   Downloaded unmp-id v2.0.0
[INFO] [stderr]   Downloaded tungstenite v0.13.0
[INFO] [stderr]   Downloaded input_buffer v0.4.0
[INFO] [stderr]   Downloaded async-tungstenite v0.13.1
[INFO] [stderr]   Downloaded riscv-types v0.1.0
[INFO] [stderr]   Downloaded interrupt v0.1.4
[INFO] [stderr]   Downloaded bare-metal v1.0.0
[INFO] [stderr]   Downloaded futures-intrusive v0.4.2
[INFO] [stderr]   Downloaded sha-1 v0.9.8
[INFO] [stderr]   Downloaded msp430 v0.4.1
[INFO] [stderr]   Downloaded riscv v0.16.0
[INFO] [stderr]   Downloaded xtensa-lx v0.13.0
[INFO] [stderr]   Downloaded riscv-macros v0.4.0
[INFO] [stderr]   Downloaded ach-ring v0.1.10
[INFO] [stderr]   Downloaded spin_loop v0.1.1
[INFO] [stderr]   Downloaded ach-util v0.1.17
[INFO] [stderr]   Downloaded ach-mpmc v0.2.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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] 39aedae168e01b42f0218e2f6132077c761270321739473a620154a1742d7410
[INFO] running `Command { std: "docker" "start" "-a" "39aedae168e01b42f0218e2f6132077c761270321739473a620154a1742d7410", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "39aedae168e01b42f0218e2f6132077c761270321739473a620154a1742d7410", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "39aedae168e01b42f0218e2f6132077c761270321739473a620154a1742d7410", kill_on_drop: false }`
[INFO] [stdout] 39aedae168e01b42f0218e2f6132077c761270321739473a620154a1742d7410
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 835968ee00c0da844947b9e0f8c5b31e4dd8eead263f1842f8dece7d996cc17d
[INFO] running `Command { std: "docker" "start" "-a" "835968ee00c0da844947b9e0f8c5b31e4dd8eead263f1842f8dece7d996cc17d", kill_on_drop: false }`
[INFO] [stderr]    Compiling rustix v1.1.4
[INFO] [stderr]    Compiling futures-lite v2.6.1
[INFO] [stderr]    Compiling async-task v4.7.1
[INFO] [stderr]    Compiling async-io v2.6.0
[INFO] [stderr]    Compiling generic-array v0.14.9
[INFO] [stderr]    Compiling smallvec v1.15.1
[INFO] [stderr]    Compiling log v0.4.29
[INFO] [stderr]    Compiling atomic v0.5.3
[INFO] [stderr]    Compiling getrandom v0.2.17
[INFO] [stderr]    Compiling spin_loop v0.1.1
[INFO] [stderr]    Compiling event-listener v5.4.1
[INFO] [stderr]    Compiling piper v0.2.5
[INFO] [stderr]    Compiling futures-sink v0.3.32
[INFO] [stderr]    Compiling percent-encoding v2.3.2
[INFO] [stderr]    Compiling thiserror-impl v1.0.69
[INFO] [stderr]    Compiling crc16 v0.4.0
[INFO] [stderr]    Compiling async-channel v1.9.0
[INFO] [stderr]    Compiling futures-util v0.3.32
[INFO] [stderr]    Compiling form_urlencoded v1.2.2
[INFO] [stderr]    Compiling icu_normalizer v2.2.0
[INFO] [stderr]    Compiling input_buffer v0.4.0
[INFO] [stderr]    Compiling ach-util v0.1.17
[INFO] [stderr]    Compiling rand_core v0.6.4
[INFO] [stderr]    Compiling kv-log-macro v1.0.7
[INFO] [stderr]    Compiling spin v0.9.8
[INFO] [stderr]    Compiling futures-intrusive v0.4.2
[INFO] [stderr]    Compiling fixed-queue v0.3.11
[INFO] [stderr]    Compiling event-listener-strategy v0.5.4
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling ach-ring v0.1.10
[INFO] [stderr]    Compiling unmp-id v2.0.0
[INFO] [stderr]    Compiling async-channel v2.5.0
[INFO] [stderr]    Compiling async-lock v3.4.2
[INFO] [stderr]    Compiling ach-mpmc v0.2.1
[INFO] [stderr]    Compiling idna_adapter v1.2.1
[INFO] [stderr]    Compiling rand v0.8.6
[INFO] [stderr]    Compiling idna v1.1.0
[INFO] [stderr]    Compiling blocking v1.6.2
[INFO] [stderr]    Compiling async-executor v1.14.0
[INFO] [stderr]    Compiling unmp-link v0.7.0
[INFO] [stderr]    Compiling digest v0.9.0
[INFO] [stderr]    Compiling block-buffer v0.9.0
[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/unmp-link-0.7.0/src/lib.rs:6:1
[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
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "835968ee00c0da844947b9e0f8c5b31e4dd8eead263f1842f8dece7d996cc17d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "835968ee00c0da844947b9e0f8c5b31e4dd8eead263f1842f8dece7d996cc17d", kill_on_drop: false }`
[INFO] [stdout] 835968ee00c0da844947b9e0f8c5b31e4dd8eead263f1842f8dece7d996cc17d
