[INFO] crate accessors 0.0.3 is already in cache
[INFO] extracting crate accessors 0.0.3 into work/ex/beta-1.38-1/sources/1.37.0/reg/accessors/0.0.3
[INFO] extracting crate accessors 0.0.3 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/accessors/0.0.3
[INFO] validating manifest of accessors-0.0.3 on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of accessors-0.0.3 on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing accessors-0.0.3
[INFO] finished frobbing accessors-0.0.3
[INFO] frobbed toml for accessors-0.0.3 written to work/ex/beta-1.38-1/sources/1.37.0/reg/accessors/0.0.3/Cargo.toml
[INFO] started frobbing accessors-0.0.3
[INFO] finished frobbing accessors-0.0.3
[INFO] frobbed toml for accessors-0.0.3 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/accessors/0.0.3/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing accessors-0.0.3 against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-6/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/accessors/0.0.3:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] a7d891ffc110d38db19f9c0ca052f0c9be1041a9133c5798937fc8a60faf8632
[INFO] running `"docker" "start" "-a" "a7d891ffc110d38db19f9c0ca052f0c9be1041a9133c5798937fc8a60faf8632"`
[INFO] [stderr]    Compiling syn v0.9.2
[INFO] [stderr]    Compiling accessors v0.0.3 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/lib.rs:6:1
[INFO] [stderr]   |
[INFO] [stderr] 6 | #![feature(proc_macro, proc_macro_lib)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused `#[macro_use]` import
[INFO] [stderr]  --> src/lib.rs:8:1
[INFO] [stderr]   |
[INFO] [stderr] 8 | #[macro_use]
[INFO] [stderr]   | ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[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 `accessors`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "a7d891ffc110d38db19f9c0ca052f0c9be1041a9133c5798937fc8a60faf8632"`
[INFO] running `"docker" "rm" "-f" "a7d891ffc110d38db19f9c0ca052f0c9be1041a9133c5798937fc8a60faf8632"`
[INFO] [stdout] a7d891ffc110d38db19f9c0ca052f0c9be1041a9133c5798937fc8a60faf8632