[INFO] crate futures-await-test-preview 0.3.0-alpha.16 is already in cache
[INFO] extracting crate futures-await-test-preview 0.3.0-alpha.16 into work/ex/beta-1.38-1/sources/1.37.0/reg/futures-await-test-preview/0.3.0-alpha.16
[INFO] extracting crate futures-await-test-preview 0.3.0-alpha.16 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/futures-await-test-preview/0.3.0-alpha.16
[INFO] validating manifest of futures-await-test-preview-0.3.0-alpha.16 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 futures-await-test-preview-0.3.0-alpha.16 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 futures-await-test-preview-0.3.0-alpha.16
[INFO] finished frobbing futures-await-test-preview-0.3.0-alpha.16
[INFO] frobbed toml for futures-await-test-preview-0.3.0-alpha.16 written to work/ex/beta-1.38-1/sources/1.37.0/reg/futures-await-test-preview/0.3.0-alpha.16/Cargo.toml
[INFO] started frobbing futures-await-test-preview-0.3.0-alpha.16
[INFO] finished frobbing futures-await-test-preview-0.3.0-alpha.16
[INFO] frobbed toml for futures-await-test-preview-0.3.0-alpha.16 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/futures-await-test-preview/0.3.0-alpha.16/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 futures-await-test-preview-0.3.0-alpha.16 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/futures-await-test-preview/0.3.0-alpha.16:/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] a086b937dd6432ab6a19e0d63db5046cd89fa9708f644a99bef4d6e31e09665e
[INFO] running `"docker" "start" "-a" "a086b937dd6432ab6a19e0d63db5046cd89fa9708f644a99bef4d6e31e09665e"`
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-executor-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-await-test-macro-preview v0.3.0-alpha.16
[INFO] [stderr]    Compiling futures-await-test-preview v0.3.0-alpha.16 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 11.88s
[INFO] running `"docker" "inspect" "a086b937dd6432ab6a19e0d63db5046cd89fa9708f644a99bef4d6e31e09665e"`
[INFO] running `"docker" "rm" "-f" "a086b937dd6432ab6a19e0d63db5046cd89fa9708f644a99bef4d6e31e09665e"`
[INFO] [stdout] a086b937dd6432ab6a19e0d63db5046cd89fa9708f644a99bef4d6e31e09665e
[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/futures-await-test-preview/0.3.0-alpha.16:/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] 7dbfaf09f32cfe36f38eadfda5f1cc207f5332afe837050e4d9c87b833879695
[INFO] running `"docker" "start" "-a" "7dbfaf09f32cfe36f38eadfda5f1cc207f5332afe837050e4d9c87b833879695"`
[INFO] [stderr]    Compiling futures-await-test-preview v0.3.0-alpha.16 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> tests/test.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(async_await)]
[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 `futures-await-test-preview`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "7dbfaf09f32cfe36f38eadfda5f1cc207f5332afe837050e4d9c87b833879695"`
[INFO] running `"docker" "rm" "-f" "7dbfaf09f32cfe36f38eadfda5f1cc207f5332afe837050e4d9c87b833879695"`
[INFO] [stdout] 7dbfaf09f32cfe36f38eadfda5f1cc207f5332afe837050e4d9c87b833879695