[INFO] fetching crate mula 0.1.1...
[INFO] testing mula-0.1.1 against 1.91.0 for beta-1.92-2
[INFO] extracting crate mula 0.1.1 into /workspace/builds/worker-5-tc1/source
[INFO] started tweaking crates.io crate mula 0.1.1
[INFO] finished tweaking crates.io crate mula 0.1.1
[INFO] tweaked toml for crates.io crate mula 0.1.1 written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate mula 0.1.1 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] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 31 packages to latest compatible versions
[INFO] [stderr]       Adding parking_lot v0.11.2 (available: v0.12.5)
[INFO] [stderr]       Adding rand v0.7.3 (available: v0.9.2)
[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]  Downloading crates ...
[INFO] [stderr]   Downloaded instant v0.1.13
[INFO] [stderr]   Downloaded spmc v0.3.0
[INFO] [stderr]   Downloaded mula_proc_macro v0.1.0
[INFO] [stderr]   Downloaded parking_lot_core v0.8.6
[INFO] [stderr]   Downloaded redox_syscall v0.2.16
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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] 444331b0ff5aa7fe26ec84ac747f32d41cd9e0d74b140ba35608a7e3322ec9e1
[INFO] running `Command { std: "docker" "start" "-a" "444331b0ff5aa7fe26ec84ac747f32d41cd9e0d74b140ba35608a7e3322ec9e1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "444331b0ff5aa7fe26ec84ac747f32d41cd9e0d74b140ba35608a7e3322ec9e1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "444331b0ff5aa7fe26ec84ac747f32d41cd9e0d74b140ba35608a7e3322ec9e1", kill_on_drop: false }`
[INFO] [stdout] 444331b0ff5aa7fe26ec84ac747f32d41cd9e0d74b140ba35608a7e3322ec9e1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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] 7b39773d69edb685c94468b7eddb3934362ba0e143299a114034ea7473490d3f
[INFO] running `Command { std: "docker" "start" "-a" "7b39773d69edb685c94468b7eddb3934362ba0e143299a114034ea7473490d3f", kill_on_drop: false }`
[INFO] [stderr]    Compiling parking_lot_core v0.8.6
[INFO] [stderr]    Compiling cfg-if v1.0.4
[INFO] [stderr]    Compiling spmc v0.3.0
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling lock_api v0.4.14
[INFO] [stderr]    Compiling instant v0.1.13
[INFO] [stderr]    Compiling parking_lot v0.11.2
[INFO] [stderr]    Compiling mula_proc_macro v0.1.0
[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/mula_proc_macro-0.1.0/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(proc_macro_diagnostic)]
[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 `mula_proc_macro` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "7b39773d69edb685c94468b7eddb3934362ba0e143299a114034ea7473490d3f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7b39773d69edb685c94468b7eddb3934362ba0e143299a114034ea7473490d3f", kill_on_drop: false }`
[INFO] [stdout] 7b39773d69edb685c94468b7eddb3934362ba0e143299a114034ea7473490d3f
