[INFO] fetching crate genref 0.8.0...
[INFO] testing genref-0.8.0 against 1.90.0 for beta-1.91-3
[INFO] extracting crate genref 0.8.0 into /workspace/builds/worker-0-tc1/source
[INFO] started tweaking crates.io crate genref 0.8.0
[INFO] finished tweaking crates.io crate genref 0.8.0
[INFO] tweaked toml for crates.io crate genref 0.8.0 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate genref 0.8.0 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 20 packages to latest compatible versions
[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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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] bf9c1f4a4cba8b3773b549f73fca6b79a24ee3728801cb38c6f148698ad273ab
[INFO] running `Command { std: "docker" "start" "-a" "bf9c1f4a4cba8b3773b549f73fca6b79a24ee3728801cb38c6f148698ad273ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bf9c1f4a4cba8b3773b549f73fca6b79a24ee3728801cb38c6f148698ad273ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bf9c1f4a4cba8b3773b549f73fca6b79a24ee3728801cb38c6f148698ad273ab", kill_on_drop: false }`
[INFO] [stdout] bf9c1f4a4cba8b3773b549f73fca6b79a24ee3728801cb38c6f148698ad273ab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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] 1fab1e6ad1a4c4ff3f4e25901932dff8d7481309a1f4a6860302bff5c9533af4
[INFO] running `Command { std: "docker" "start" "-a" "1fab1e6ad1a4c4ff3f4e25901932dff8d7481309a1f4a6860302bff5c9533af4", kill_on_drop: false }`
[INFO] [stderr]    Compiling parking_lot_core v0.9.11
[INFO] [stderr]    Compiling parking_lot v0.12.4
[INFO] [stderr]    Compiling genref v0.8.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable 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: variable `dq` is assigned to, but never used
[INFO] [stdout]    --> src/global.rs:123:13
[INFO] [stdout]     |
[INFO] [stdout] 123 |         let dq;
[INFO] [stdout]     |             ^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_dq` instead
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `dq` is never read
[INFO] [stdout]    --> src/global.rs:125:27
[INFO] [stdout]     |
[INFO] [stdout] 125 |             Ok(mut wl) => dq = DropQueue::clear(&mut wl),
[INFO] [stdout]     |                           ^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` 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 `genref` (lib) due to 1 previous error; 2 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "1fab1e6ad1a4c4ff3f4e25901932dff8d7481309a1f4a6860302bff5c9533af4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1fab1e6ad1a4c4ff3f4e25901932dff8d7481309a1f4a6860302bff5c9533af4", kill_on_drop: false }`
[INFO] [stdout] 1fab1e6ad1a4c4ff3f4e25901932dff8d7481309a1f4a6860302bff5c9533af4