[INFO] updating cached repository https://github.com/silversupreme/reckon
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1f31eb6ef6455b21d35fac53fbb4470315d5100f
[INFO] testing silversupreme/reckon/1f31eb6ef6455b21d35fac53fbb4470315d5100f against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsilversupreme%2Freckon" "/workspace/builds/worker-50/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-50/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/silversupreme/reckon on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/silversupreme/reckon
[INFO] finished tweaking git repo https://github.com/silversupreme/reckon
[INFO] tweaked toml for git repo https://github.com/silversupreme/reckon written to /workspace/builds/worker-50/source/Cargo.toml
[INFO] crate git repo https://github.com/silversupreme/reckon already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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-50/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-50/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2363862f93a506afcafc142faa83787edd30b957b8d1b3fe9043f9674e45e0fe
[INFO] running `Command { std: "docker" "start" "-a" "2363862f93a506afcafc142faa83787edd30b957b8d1b3fe9043f9674e45e0fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2363862f93a506afcafc142faa83787edd30b957b8d1b3fe9043f9674e45e0fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2363862f93a506afcafc142faa83787edd30b957b8d1b3fe9043f9674e45e0fe", kill_on_drop: false }`
[INFO] [stdout] 2363862f93a506afcafc142faa83787edd30b957b8d1b3fe9043f9674e45e0fe
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-50/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-50/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 43236c6961be198ce2df6a5ce611d59af38f5560e32908c1b23bab863577286c
[INFO] running `Command { std: "docker" "start" "-a" "43236c6961be198ce2df6a5ce611d59af38f5560e32908c1b23bab863577286c", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling winapi-build v0.1.1
[INFO] [stderr]    Compiling libc v0.2.17
[INFO] [stderr]    Compiling winapi v0.2.8
[INFO] [stderr]    Compiling regex-syntax v0.3.9
[INFO] [stderr]    Compiling utf8-ranges v0.1.3
[INFO] [stderr]    Compiling kernel32-sys v0.2.2
[INFO] [stderr]    Compiling memchr v0.1.11
[INFO] [stderr]    Compiling thread-id v2.0.0
[INFO] [stderr]    Compiling thread_local v0.2.7
[INFO] [stderr]    Compiling aho-corasick v0.5.3
[INFO] [stderr]    Compiling regex v0.1.80
[INFO] [stderr]    Compiling reckon v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(io)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `chars` found for mutable reference `&mut ChildStdout` in the current scope
[INFO] [stdout]    --> src/base.rs:154:28
[INFO] [stdout]     |
[INFO] [stdout] 154 |         let mut c = stdout.chars();
[INFO] [stdout]     |                            ^^^^^ method not found in `&mut ChildStdout`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0599.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `reckon` due to 3 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "43236c6961be198ce2df6a5ce611d59af38f5560e32908c1b23bab863577286c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "43236c6961be198ce2df6a5ce611d59af38f5560e32908c1b23bab863577286c", kill_on_drop: false }`
[INFO] [stdout] 43236c6961be198ce2df6a5ce611d59af38f5560e32908c1b23bab863577286c