[INFO] fetching crate kll-core 0.1.8...
[INFO] testing kll-core-0.1.8 against master#562dee4820c458d823175268e41601d4c060588a for pr-154210-1
[INFO] extracting crate kll-core 0.1.8 into /workspace/builds/worker-0-tc1/source
[INFO] started tweaking crates.io crate kll-core 0.1.8
[INFO] finished tweaking crates.io crate kll-core 0.1.8
[INFO] tweaked toml for crates.io crate kll-core 0.1.8 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate kll-core 0.1.8 on toolchain 562dee4820c458d823175268e41601d4c060588a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+562dee4820c458d823175268e41601d4c060588a" "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" "+562dee4820c458d823175268e41601d4c060588a" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 79 packages to latest compatible versions
[INFO] [stderr]       Adding defmt v0.3.100 (available: v1.0.1)
[INFO] [stderr]       Adding enum-primitive-derive v0.2.2 (available: v0.3.0)
[INFO] [stderr]       Adding flexi_logger v0.25.6 (available: v0.31.8)
[INFO] [stderr]       Adding heapless v0.7.17 (available: v0.9.2)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+562dee4820c458d823175268e41601d4c060588a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded enum-primitive-derive v0.2.2
[INFO] [stderr]   Downloaded defmt v0.3.100
[INFO] [stderr]   Downloaded nu-ansi-term v0.49.0
[INFO] [stderr]   Downloaded defmt-parser v1.0.0
[INFO] [stderr]   Downloaded defmt-macros v1.0.1
[INFO] [stderr]   Downloaded kll-hid v0.1.2
[INFO] [stderr]   Downloaded kll-macros v0.1.2
[INFO] [stderr]   Downloaded defmt v1.0.1
[INFO] [stderr]   Downloaded flexi_logger v0.25.6
[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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+562dee4820c458d823175268e41601d4c060588a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d104e0b4e78cc30548ec3d724209d592835362663d55a70bda64c20d10a7e462
[INFO] running `Command { std: "docker" "start" "-a" "d104e0b4e78cc30548ec3d724209d592835362663d55a70bda64c20d10a7e462", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d104e0b4e78cc30548ec3d724209d592835362663d55a70bda64c20d10a7e462", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d104e0b4e78cc30548ec3d724209d592835362663d55a70bda64c20d10a7e462", kill_on_drop: false }`
[INFO] [stdout] d104e0b4e78cc30548ec3d724209d592835362663d55a70bda64c20d10a7e462
[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=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-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" "+562dee4820c458d823175268e41601d4c060588a" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d03567d6360011651d358cbf7612e35b96bfc7898cd9580940906cb5a31c742d
[INFO] running `Command { std: "docker" "start" "-a" "d03567d6360011651d358cbf7612e35b96bfc7898cd9580940906cb5a31c742d", kill_on_drop: false }`
[INFO] [stderr]    Compiling semver v1.0.28
[INFO] [stderr]    Compiling byteorder v1.5.0
[INFO] [stderr]    Compiling spin v0.9.8
[INFO] [stderr]    Compiling static_assertions v1.1.0
[INFO] [stderr]    Compiling kll-hid v0.1.2
[INFO] [stderr]    Compiling kll-macros v0.1.2
[INFO] [stderr]    Compiling enum-primitive-derive v0.2.2
[INFO] [stderr]    Compiling hash32 v0.2.1
[INFO] [stderr]    Compiling rustc_version v0.4.1
[INFO] [stderr]    Compiling heapless v0.7.17
[INFO] [stderr]    Compiling kll-core v0.1.8 (/opt/rustwide/workdir)
[INFO] [stdout] error: let chains are only allowed in Rust 2024 or later
[INFO] [stdout]    --> src/layout/mod.rs:322:79
[INFO] [stdout]     |
[INFO] [stdout] 322 |         let layer_guides = if capability_state != CapabilityEvent::Initial && let Some((layer, _layer_state)) = cache_hit {
[INFO] [stdout]     |                                                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `let_chains` has been stable since 1.88.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(let_chains)]
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `kll-core` (lib) due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "d03567d6360011651d358cbf7612e35b96bfc7898cd9580940906cb5a31c742d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d03567d6360011651d358cbf7612e35b96bfc7898cd9580940906cb5a31c742d", kill_on_drop: false }`
[INFO] [stdout] d03567d6360011651d358cbf7612e35b96bfc7898cd9580940906cb5a31c742d