[INFO] cloning repository https://github.com/PhotonQuantum/l-lang-parser-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/PhotonQuantum/l-lang-parser-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPhotonQuantum%2Fl-lang-parser-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPhotonQuantum%2Fl-lang-parser-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 828b04f0164a163345e876106e3a5c636bcf24a5
[INFO] testing PhotonQuantum/l-lang-parser-rs against beta-2021-01-01 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPhotonQuantum%2Fl-lang-parser-rs" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/PhotonQuantum/l-lang-parser-rs on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/PhotonQuantum/l-lang-parser-rs
[INFO] finished tweaking git repo https://github.com/PhotonQuantum/l-lang-parser-rs
[INFO] tweaked toml for git repo https://github.com/PhotonQuantum/l-lang-parser-rs written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/PhotonQuantum/l-lang-parser-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded syn v1.0.50
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2b5bed090322c492442a6888f23a3dcefeff9eeae1351549b5ed1c6e077c638a
[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" "2b5bed090322c492442a6888f23a3dcefeff9eeae1351549b5ed1c6e077c638a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2b5bed090322c492442a6888f23a3dcefeff9eeae1351549b5ed1c6e077c638a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2b5bed090322c492442a6888f23a3dcefeff9eeae1351549b5ed1c6e077c638a", kill_on_drop: false }`
[INFO] [stdout] 2b5bed090322c492442a6888f23a3dcefeff9eeae1351549b5ed1c6e077c638a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4b833368e4d4de086f2db01074cfd34faadd2704dc84227d9e09337b4a4aef79
[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" "4b833368e4d4de086f2db01074cfd34faadd2704dc84227d9e09337b4a4aef79", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.50
[INFO] [stderr]    Compiling libc v0.2.80
[INFO] [stderr]    Compiling ucd-trie v0.1.3
[INFO] [stderr]    Compiling maplit v1.0.2
[INFO] [stderr]    Compiling remove_dir_all v0.5.3
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling pest v2.1.3
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling pest_meta v2.1.3
[INFO] [stderr]    Compiling tempdir v0.3.7
[INFO] [stderr]    Compiling pest_generator v2.1.3
[INFO] [stderr]    Compiling thiserror-impl v1.0.22
[INFO] [stderr]    Compiling pest_derive v2.1.0
[INFO] [stderr]    Compiling thiserror v1.0.22
[INFO] [stderr]    Compiling which v4.0.2
[INFO] [stderr]    Compiling toy_lang_parser_rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iterator_fold_self, box_syntax, box_patterns)]
[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 `toy_lang_parser_rs`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "4b833368e4d4de086f2db01074cfd34faadd2704dc84227d9e09337b4a4aef79", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b833368e4d4de086f2db01074cfd34faadd2704dc84227d9e09337b4a4aef79", kill_on_drop: false }`
[INFO] [stdout] 4b833368e4d4de086f2db01074cfd34faadd2704dc84227d9e09337b4a4aef79