[INFO] fetching crate myser 0.1.0...
[INFO] testing myser-0.1.0 against 1.91.0 for beta-1.92-2
[INFO] extracting crate myser 0.1.0 into /workspace/builds/worker-2-tc1/source
[INFO] started tweaking crates.io crate myser 0.1.0
[INFO] finished tweaking crates.io crate myser 0.1.0
[INFO] tweaked toml for crates.io crate myser 0.1.0 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate myser 0.1.0 on toolchain 1.91.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate myser 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded lock_api v0.4.7
[INFO] [stderr]   Downloaded critical-section v0.2.7
[INFO] [stderr]   Downloaded bare-metal v0.2.5
[INFO] [stderr]   Downloaded bitfield v0.13.2
[INFO] [stderr]   Downloaded nb v0.1.3
[INFO] [stderr]   Downloaded embedded-hal v0.2.7
[INFO] [stderr]   Downloaded nb v1.0.0
[INFO] [stderr]   Downloaded riscv-target v0.1.2
[INFO] [stderr]   Downloaded bare-metal v1.0.0
[INFO] [stderr]   Downloaded cortex-m v0.7.5
[INFO] [stderr]   Downloaded riscv v0.7.0
[INFO] [stderr]   Downloaded heapless v0.7.15
[INFO] [stderr]   Downloaded bit_field v0.10.1
[INFO] [stderr]   Downloaded atomic-polyfill v0.1.8
[INFO] [stderr]   Downloaded aho-corasick v0.7.18
[INFO] [stderr]   Downloaded semver v1.0.12
[INFO] [stderr]   Downloaded volatile-register v0.2.1
[INFO] [stderr]   Downloaded regex-syntax v0.6.27
[INFO] [stderr]   Downloaded regex v1.6.0
[INFO] [stderr]   Downloaded rustc_version v0.4.0
[INFO] [stderr]   Downloaded spin v0.9.4
[INFO] [stderr]   Downloaded nom v7.1.1
[INFO] [stderr]   Downloaded vcell v0.1.3
[INFO] [stderr]   Downloaded hash32 v0.2.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+1.91.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f972a73c420976f4e5e3404643d572692bf1ff28e6f8eb2e4697b8fb82eb5d86
[INFO] running `Command { std: "docker" "start" "-a" "f972a73c420976f4e5e3404643d572692bf1ff28e6f8eb2e4697b8fb82eb5d86", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f972a73c420976f4e5e3404643d572692bf1ff28e6f8eb2e4697b8fb82eb5d86", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f972a73c420976f4e5e3404643d572692bf1ff28e6f8eb2e4697b8fb82eb5d86", kill_on_drop: false }`
[INFO] [stdout] f972a73c420976f4e5e3404643d572692bf1ff28e6f8eb2e4697b8fb82eb5d86
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+1.91.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7cde77cb5b4a9a98216f699d4cd034fdb0ce7ff5141fd10eeb70568f42b75975
[INFO] running `Command { std: "docker" "start" "-a" "7cde77cb5b4a9a98216f699d4cd034fdb0ce7ff5141fd10eeb70568f42b75975", kill_on_drop: false }`
[INFO] [stderr]    Compiling semver v1.0.12
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling minimal-lexical v0.2.1
[INFO] [stderr]    Compiling hash32 v0.2.1
[INFO] [stderr]    Compiling nom v7.1.1
[INFO] [stderr]    Compiling lock_api v0.4.7
[INFO] [stderr]    Compiling rustc_version v0.4.0
[INFO] [stderr]    Compiling spin v0.9.4
[INFO] [stderr]    Compiling heapless v0.7.15
[INFO] [stderr]    Compiling myser v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(as_array_of_cells)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `as_array_of_cells` has been stable since 1.91.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(as_array_of_cells)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` 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 `myser` (bin "myser") due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "7cde77cb5b4a9a98216f699d4cd034fdb0ce7ff5141fd10eeb70568f42b75975", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7cde77cb5b4a9a98216f699d4cd034fdb0ce7ff5141fd10eeb70568f42b75975", kill_on_drop: false }`
[INFO] [stdout] 7cde77cb5b4a9a98216f699d4cd034fdb0ce7ff5141fd10eeb70568f42b75975