[INFO] crate percy-webapis 0.0.2 is already in cache
[INFO] testing percy-webapis-0.0.2 against beta-2019-09-28 for beta-1.39-1
[INFO] extracting crate percy-webapis 0.0.2 into work/builds/worker-4/source
[INFO] validating manifest of crates.io crate percy-webapis 0.0.2 on toolchain beta-2019-09-28
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate percy-webapis 0.0.2
[INFO] finished tweaking crates.io crate percy-webapis 0.0.2
[INFO] tweaked toml for crates.io crate percy-webapis 0.0.2 written to work/builds/worker-4/source/Cargo.toml
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2019-09-28" "build" "--frozen"`
[INFO] [stdout] 9b9fc2c590a112e423739e67e511c28e7d7d2a7178772e5a88a095d9ee9a8b9b
[INFO] running `"docker" "start" "-a" "9b9fc2c590a112e423739e67e511c28e7d7d2a7178772e5a88a095d9ee9a8b9b"`
[INFO] [stderr]    Compiling percy-webapis v0.0.2 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(use_extern_macros)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/lib.rs:57:73
[INFO] [stderr]    |
[INFO] [stderr] 57 |     pub fn add_event_listener(this: &Element, event: &str, cb: &Closure<Fn()>);
[INFO] [stderr]    |                                                                         ^^^^ help: use `dyn`: `dyn Fn()`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/lib.rs:57:73
[INFO] [stderr]    |
[INFO] [stderr] 57 |     pub fn add_event_listener(this: &Element, event: &str, cb: &Closure<Fn()>);
[INFO] [stderr]    |                                                                         ^^^^ help: use `dyn`: `dyn Fn()`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `percy-webapis`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "9b9fc2c590a112e423739e67e511c28e7d7d2a7178772e5a88a095d9ee9a8b9b"`
[INFO] running `"docker" "rm" "-f" "9b9fc2c590a112e423739e67e511c28e7d7d2a7178772e5a88a095d9ee9a8b9b"`
[INFO] [stdout] 9b9fc2c590a112e423739e67e511c28e7d7d2a7178772e5a88a095d9ee9a8b9b