[INFO] crate takkerus 0.3.0 is already in cache
[INFO] testing takkerus-0.3.0 against beta-2019-09-28 for beta-1.39-1
[INFO] extracting crate takkerus 0.3.0 into work/builds/worker-9/source
[INFO] validating manifest of crates.io crate takkerus 0.3.0 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 takkerus 0.3.0
[INFO] finished tweaking crates.io crate takkerus 0.3.0
[INFO] tweaked toml for crates.io crate takkerus 0.3.0 written to work/builds/worker-9/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-9/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-9/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] 49338b8b01511a88d8290a67dc777e63ad69ca47f9f1cdc247fcdda7959eb167
[INFO] running `"docker" "start" "-a" "49338b8b01511a88d8290a67dc777e63ad69ca47f9f1cdc247fcdda7959eb167"`
[INFO] [stderr]    Compiling zero_sum v1.2.0
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/zero_sum-1.2.0/src/lib.rs:74:1
[INFO] [stderr]    |
[INFO] [stderr] 74 | #![feature(test)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^
[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 `zero_sum`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "49338b8b01511a88d8290a67dc777e63ad69ca47f9f1cdc247fcdda7959eb167"`
[INFO] running `"docker" "rm" "-f" "49338b8b01511a88d8290a67dc777e63ad69ca47f9f1cdc247fcdda7959eb167"`
[INFO] [stdout] 49338b8b01511a88d8290a67dc777e63ad69ca47f9f1cdc247fcdda7959eb167