[INFO] fetching crate mula 0.1.1...
[INFO] testing mula-0.1.1 against 1.60.0 for beta-1.61-1
[INFO] extracting crate mula 0.1.1 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate mula 0.1.1 on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[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/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded spmc v0.3.0
[INFO] [stderr]   Downloaded mula_proc_macro v0.1.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7d3c447e1a552f264498569392e8c13af223bd66a8f444cbbb0c7525ed065171
[INFO] running `Command { std: "docker" "start" "-a" "7d3c447e1a552f264498569392e8c13af223bd66a8f444cbbb0c7525ed065171", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7d3c447e1a552f264498569392e8c13af223bd66a8f444cbbb0c7525ed065171", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d3c447e1a552f264498569392e8c13af223bd66a8f444cbbb0c7525ed065171", kill_on_drop: false }`
[INFO] [stdout] 7d3c447e1a552f264498569392e8c13af223bd66a8f444cbbb0c7525ed065171
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fff8a95b99e21dcda88437d54a822dc0cd8cdf2a9bc1d6843957628a6374e1f3
[INFO] running `Command { std: "docker" "start" "-a" "fff8a95b99e21dcda88437d54a822dc0cd8cdf2a9bc1d6843957628a6374e1f3", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.37
[INFO] [stderr]    Compiling libc v0.2.123
[INFO] [stderr]    Compiling parking_lot_core v0.8.5
[INFO] [stderr]    Compiling syn v1.0.91
[INFO] [stderr]    Compiling smallvec v1.8.0
[INFO] [stderr]    Compiling spmc v0.3.0
[INFO] [stderr]    Compiling lock_api v0.4.7
[INFO] [stderr]    Compiling instant v0.1.12
[INFO] [stderr]    Compiling quote v1.0.18
[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/github.com-1ecc6299db9ec823/mula_proc_macro-0.1.0/src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(proc_macro_diagnostic)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[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` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "fff8a95b99e21dcda88437d54a822dc0cd8cdf2a9bc1d6843957628a6374e1f3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fff8a95b99e21dcda88437d54a822dc0cd8cdf2a9bc1d6843957628a6374e1f3", kill_on_drop: false }`
[INFO] [stdout] fff8a95b99e21dcda88437d54a822dc0cd8cdf2a9bc1d6843957628a6374e1f3