[INFO] updating cached repository https://github.com/UnicodeSnowman/writing_an_interpreter_in_rust
[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] 0952a8d5bbdba06124f3cc94e5528daa4a81c828
[INFO] testing UnicodeSnowman/writing_an_interpreter_in_rust against beta-2020-07-24 for beta-1.46-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FUnicodeSnowman%2Fwriting_an_interpreter_in_rust" "/workspace/builds/worker-9/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/UnicodeSnowman/writing_an_interpreter_in_rust on toolchain beta-2020-07-24
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/UnicodeSnowman/writing_an_interpreter_in_rust
[INFO] finished tweaking git repo https://github.com/UnicodeSnowman/writing_an_interpreter_in_rust
[INFO] tweaked toml for git repo https://github.com/UnicodeSnowman/writing_an_interpreter_in_rust written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/UnicodeSnowman/writing_an_interpreter_in_rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 821ccf41022149d16a3c5492dd1727d456850ff36c7d96b618034b240bc2db31
[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" "821ccf41022149d16a3c5492dd1727d456850ff36c7d96b618034b240bc2db31", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "821ccf41022149d16a3c5492dd1727d456850ff36c7d96b618034b240bc2db31", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "821ccf41022149d16a3c5492dd1727d456850ff36c7d96b618034b240bc2db31", kill_on_drop: false }`
[INFO] [stdout] 821ccf41022149d16a3c5492dd1727d456850ff36c7d96b618034b240bc2db31
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d82e184879aa6e5fcb8f3c8e1c33dd30d0bd01801148649e07079b4a1cacaef9
[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" "d82e184879aa6e5fcb8f3c8e1c33dd30d0bd01801148649e07079b4a1cacaef9", kill_on_drop: false }`
[INFO] [stderr]    Compiling writing_an_interpreter_in_rust 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(slice_patterns)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/ast.rs:16:29
[INFO] [stdout]    |
[INFO] [stdout] 16 |     pub statements: Vec<Box<Statement>>
[INFO] [stdout]    |                             ^^^^^^^^^ help: use `dyn`: `dyn Statement`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/ast.rs:32:16
[INFO] [stdout]    |
[INFO] [stdout] 32 |     value: Box<Expression>
[INFO] [stdout]    |                ^^^^^^^^^^ help: use `dyn`: `dyn Expression`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 warnings 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 `writing_an_interpreter_in_rust`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "d82e184879aa6e5fcb8f3c8e1c33dd30d0bd01801148649e07079b4a1cacaef9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d82e184879aa6e5fcb8f3c8e1c33dd30d0bd01801148649e07079b4a1cacaef9", kill_on_drop: false }`
[INFO] [stdout] d82e184879aa6e5fcb8f3c8e1c33dd30d0bd01801148649e07079b4a1cacaef9