[INFO] fetching crate unmp-protocol-raw 0.7.1...
[INFO] testing unmp-protocol-raw-0.7.1 against 1.90.0 for beta-1.91-3
[INFO] extracting crate unmp-protocol-raw 0.7.1 into /workspace/builds/worker-3-tc1/source
[INFO] started tweaking crates.io crate unmp-protocol-raw 0.7.1
[INFO] finished tweaking crates.io crate unmp-protocol-raw 0.7.1
[INFO] tweaked toml for crates.io crate unmp-protocol-raw 0.7.1 written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate unmp-protocol-raw 0.7.1 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]      Locking 53 packages to latest compatible versions
[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" "+1.90.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded unmp v0.7.3
[INFO] [stderr]   Downloaded ach-util v0.1.16
[INFO] [stderr]   Downloaded fixed-queue v0.3.11
[INFO] [stderr]   Downloaded spin_loop v0.1.1
[INFO] [stderr]   Downloaded ach-mpmc v0.2.0
[INFO] [stderr]   Downloaded unmp-link v0.7.0
[INFO] [stderr]   Downloaded crc16 v0.4.0
[INFO] [stderr]   Downloaded unmp-id v2.0.0
[INFO] [stderr]   Downloaded riscv v0.15.0
[INFO] [stderr]   Downloaded futures-intrusive v0.4.2
[INFO] [stderr]   Downloaded msp430 v0.4.1
[INFO] [stderr]   Downloaded riscv-macros v0.3.0
[INFO] [stderr]   Downloaded riscv-pac v0.2.0
[INFO] [stderr]   Downloaded xtensa-lx v0.12.0
[INFO] [stderr]   Downloaded interrupt v0.1.3
[INFO] [stderr]   Downloaded ach-ring v0.1.9
[INFO] [stderr]   Downloaded task-stream v0.3.7
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5dcad48100eba415e2795fdc5889d4b3b9974c241275ee88113c61c714703ca0
[INFO] running `Command { std: "docker" "start" "-a" "5dcad48100eba415e2795fdc5889d4b3b9974c241275ee88113c61c714703ca0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5dcad48100eba415e2795fdc5889d4b3b9974c241275ee88113c61c714703ca0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5dcad48100eba415e2795fdc5889d4b3b9974c241275ee88113c61c714703ca0", kill_on_drop: false }`
[INFO] [stdout] 5dcad48100eba415e2795fdc5889d4b3b9974c241275ee88113c61c714703ca0
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 121c8aed12597fcd789a4ec0f375e46bfc0d6715bc03842f4fa34c851cd52629
[INFO] running `Command { std: "docker" "start" "-a" "121c8aed12597fcd789a4ec0f375e46bfc0d6715bc03842f4fa34c851cd52629", kill_on_drop: false }`
[INFO] [stderr]    Compiling atomic v0.5.3
[INFO] [stderr]    Compiling spin_loop v0.1.1
[INFO] [stderr]    Compiling futures-core v0.3.31
[INFO] [stderr]    Compiling futures-task v0.3.31
[INFO] [stderr]    Compiling crc16 v0.4.0
[INFO] [stderr]    Compiling async-task v4.7.1
[INFO] [stderr]    Compiling fixed-queue v0.3.11
[INFO] [stderr]    Compiling unmp-id v2.0.0
[INFO] [stderr]    Compiling spin v0.9.8
[INFO] [stderr]    Compiling getrandom v0.2.16
[INFO] [stderr]    Compiling futures-util v0.3.31
[INFO] [stderr]    Compiling futures-intrusive v0.4.2
[INFO] [stderr]    Compiling ach-util v0.1.16
[INFO] [stderr]    Compiling ach-ring v0.1.9
[INFO] [stderr]    Compiling ach-mpmc v0.2.0
[INFO] [stderr]    Compiling unmp-link v0.7.0
[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" "121c8aed12597fcd789a4ec0f375e46bfc0d6715bc03842f4fa34c851cd52629", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "121c8aed12597fcd789a4ec0f375e46bfc0d6715bc03842f4fa34c851cd52629", kill_on_drop: false }`
[INFO] [stdout] 121c8aed12597fcd789a4ec0f375e46bfc0d6715bc03842f4fa34c851cd52629