[INFO] crate ezing 0.2.1 is already in cache
[INFO] extracting crate ezing 0.2.1 into work/ex/beta-1.38-1/sources/1.37.0/reg/ezing/0.2.1
[INFO] extracting crate ezing 0.2.1 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/ezing/0.2.1
[INFO] validating manifest of ezing-0.2.1 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 ezing-0.2.1 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 ezing-0.2.1
[INFO] finished frobbing ezing-0.2.1
[INFO] frobbed toml for ezing-0.2.1 written to work/ex/beta-1.38-1/sources/1.37.0/reg/ezing/0.2.1/Cargo.toml
[INFO] started frobbing ezing-0.2.1
[INFO] finished frobbing ezing-0.2.1
[INFO] frobbed toml for ezing-0.2.1 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/ezing/0.2.1/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 ezing-0.2.1 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-2/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/ezing/0.2.1:/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] 142c87febd805440a67095ab7455c543d1510d58714116d79bf26a48c9d2481c
[INFO] running `"docker" "start" "-a" "142c87febd805440a67095ab7455c543d1510d58714116d79bf26a48c9d2481c"`
[INFO] [stderr]    Compiling ezing v0.2.1 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.27s
[INFO] running `"docker" "inspect" "142c87febd805440a67095ab7455c543d1510d58714116d79bf26a48c9d2481c"`
[INFO] running `"docker" "rm" "-f" "142c87febd805440a67095ab7455c543d1510d58714116d79bf26a48c9d2481c"`
[INFO] [stdout] 142c87febd805440a67095ab7455c543d1510d58714116d79bf26a48c9d2481c
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-2/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/ezing/0.2.1:/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" "test" "--frozen" "--no-run"`
[INFO] [stdout] 058c8babc7c2a32179df10cede2bb748b62d14eaeb9f2d1e1aee01184c86446e
[INFO] running `"docker" "start" "-a" "058c8babc7c2a32179df10cede2bb748b62d14eaeb9f2d1e1aee01184c86446e"`
[INFO] [stderr]    Compiling khronos_api v2.2.0
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling token_store v0.1.2
[INFO] [stderr]    Compiling x11-dl v2.18.4
[INFO] [stderr]    Compiling freetype-sys v0.6.0
[INFO] [stderr]    Compiling xml-rs v0.7.0
[INFO] [stderr]    Compiling memmap v0.6.2
[INFO] [stderr]    Compiling dlib v0.4.1
[INFO] [stderr]    Compiling osmesa-sys v0.1.2
[INFO] [stderr]    Compiling wayland-sys v0.12.5
[INFO] [stderr]    Compiling wayland-scanner v0.12.5
[INFO] [stderr]    Compiling gl_generator v0.9.0
[INFO] [stderr]    Compiling wayland-client v0.12.5
[INFO] [stderr]    Compiling wayland-protocols v0.12.5
[INFO] [stderr]    Compiling glutin v0.14.0
[INFO] [stderr]    Compiling glium v0.21.0
[INFO] [stderr]    Compiling wayland-kbd v0.13.1
[INFO] [stderr]    Compiling wayland-window v0.13.3
[INFO] [stderr]    Compiling winit v0.12.0
[INFO] [stderr]    Compiling glium_text v0.12.0
[INFO] [stderr]    Compiling ezing v0.2.1 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/lib.rs:5:19
[INFO] [stderr]   |
[INFO] [stderr] 5 | #![cfg_attr(test, feature(concat_idents))]
[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 `ezing`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "058c8babc7c2a32179df10cede2bb748b62d14eaeb9f2d1e1aee01184c86446e"`
[INFO] running `"docker" "rm" "-f" "058c8babc7c2a32179df10cede2bb748b62d14eaeb9f2d1e1aee01184c86446e"`
[INFO] [stdout] 058c8babc7c2a32179df10cede2bb748b62d14eaeb9f2d1e1aee01184c86446e