[INFO] cloning repository https://github.com/mingyli/mrust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mingyli/mrust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmingyli%2Fmrust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmingyli%2Fmrust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c87e65902a4c4e88240728bd825d667ac7ac96cc
[INFO] testing mingyli/mrust against 1.59.0 for beta-1.60-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmingyli%2Fmrust" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mingyli/mrust on toolchain 1.59.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mingyli/mrust
[INFO] finished tweaking git repo https://github.com/mingyli/mrust
[INFO] tweaked toml for git repo https://github.com/mingyli/mrust written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/mingyli/mrust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7d6b3c6d6504992ae719cda5a34fdaed6ada82098c21b7de581ba5087b7b8e68
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "7d6b3c6d6504992ae719cda5a34fdaed6ada82098c21b7de581ba5087b7b8e68", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7d6b3c6d6504992ae719cda5a34fdaed6ada82098c21b7de581ba5087b7b8e68", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d6b3c6d6504992ae719cda5a34fdaed6ada82098c21b7de581ba5087b7b8e68", kill_on_drop: false }`
[INFO] [stdout] 7d6b3c6d6504992ae719cda5a34fdaed6ada82098c21b7de581ba5087b7b8e68
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 49ca946738a899c6207682f8c3b13e96c9b678751777d13a6c671f5203c36a97
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "49ca946738a899c6207682f8c3b13e96c9b678751777d13a6c671f5203c36a97", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.57
[INFO] [stderr]    Compiling smallvec v1.6.0
[INFO] [stderr]    Compiling beef v0.4.4
[INFO] [stderr]    Compiling inkwell v0.1.0 (https://github.com/TheDan64/inkwell?branch=master#3eab4db4)
[INFO] [stderr]    Compiling itertools v0.10.0
[INFO] [stderr]    Compiling llvm-sys v100.2.0
[INFO] [stderr]    Compiling parking_lot_core v0.8.2
[INFO] [stderr]    Compiling parking_lot v0.11.1
[INFO] [stderr]    Compiling inkwell_internals v0.2.0 (https://github.com/TheDan64/inkwell?branch=master#3eab4db4)
[INFO] [stderr]    Compiling logos-derive v0.11.5
[INFO] [stderr]    Compiling logos v0.11.4
[INFO] [stderr]    Compiling mrust 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(peekable_next_if)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `peekable_next_if` has been stable since 1.51.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(peekable_next_if)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `mrust` due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "49ca946738a899c6207682f8c3b13e96c9b678751777d13a6c671f5203c36a97", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "49ca946738a899c6207682f8c3b13e96c9b678751777d13a6c671f5203c36a97", kill_on_drop: false }`
[INFO] [stdout] 49ca946738a899c6207682f8c3b13e96c9b678751777d13a6c671f5203c36a97