[INFO] cloning repository https://github.com/macron-lang/macron-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/macron-lang/macron-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmacron-lang%2Fmacron-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmacron-lang%2Fmacron-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a918f7cd75b95eb71f313a4ed4bb8b3ec16ead97
[INFO] testing macron-lang/macron-rs against 1.60.0 for beta-1.61-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmacron-lang%2Fmacron-rs" "/workspace/builds/worker-16/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-16/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/macron-lang/macron-rs 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 git repo https://github.com/macron-lang/macron-rs
[INFO] finished tweaking git repo https://github.com/macron-lang/macron-rs
[INFO] tweaked toml for git repo https://github.com/macron-lang/macron-rs written to /workspace/builds/worker-16/source/Cargo.toml
[INFO] crate git repo https://github.com/macron-lang/macron-rs already has a lockfile, it will not be regenerated
[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]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/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] 0f70763d0b90c006d4323165cdf75df6ef2898a17e6c0287a705d331f9ffe275
[INFO] running `Command { std: "docker" "start" "-a" "0f70763d0b90c006d4323165cdf75df6ef2898a17e6c0287a705d331f9ffe275", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0f70763d0b90c006d4323165cdf75df6ef2898a17e6c0287a705d331f9ffe275", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0f70763d0b90c006d4323165cdf75df6ef2898a17e6c0287a705d331f9ffe275", kill_on_drop: false }`
[INFO] [stdout] 0f70763d0b90c006d4323165cdf75df6ef2898a17e6c0287a705d331f9ffe275
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/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] 02daf9331a5f25c3f5cd2f176c95334a83494bed8c2a5b20c5316c796aaf8b1a
[INFO] running `Command { std: "docker" "start" "-a" "02daf9331a5f25c3f5cd2f176c95334a83494bed8c2a5b20c5316c796aaf8b1a", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.29
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling libc v0.2.101
[INFO] [stderr]    Compiling unicode-width v0.1.8
[INFO] [stderr]    Compiling ansi_term v0.11.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling structopt-derive v0.4.16
[INFO] [stderr]    Compiling structopt v0.3.23
[INFO] [stderr]    Compiling macron-rs 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:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(stdio_locked, new_uninit)]
[INFO] [stdout]   |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:26
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(stdio_locked, new_uninit)]
[INFO] [stdout]   |                          ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `macron-rs` due to 3 previous errors
[INFO] running `Command { std: "docker" "inspect" "02daf9331a5f25c3f5cd2f176c95334a83494bed8c2a5b20c5316c796aaf8b1a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "02daf9331a5f25c3f5cd2f176c95334a83494bed8c2a5b20c5316c796aaf8b1a", kill_on_drop: false }`
[INFO] [stdout] 02daf9331a5f25c3f5cd2f176c95334a83494bed8c2a5b20c5316c796aaf8b1a