[INFO] crate fluence-sdk-main 0.1.5 is already in cache
[INFO] extracting crate fluence-sdk-main 0.1.5 into work/ex/beta-1.38-1/sources/1.37.0/reg/fluence-sdk-main/0.1.5
[INFO] extracting crate fluence-sdk-main 0.1.5 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/fluence-sdk-main/0.1.5
[INFO] validating manifest of fluence-sdk-main-0.1.5 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 fluence-sdk-main-0.1.5 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 fluence-sdk-main-0.1.5
[INFO] finished frobbing fluence-sdk-main-0.1.5
[INFO] frobbed toml for fluence-sdk-main-0.1.5 written to work/ex/beta-1.38-1/sources/1.37.0/reg/fluence-sdk-main/0.1.5/Cargo.toml
[INFO] started frobbing fluence-sdk-main-0.1.5
[INFO] finished frobbing fluence-sdk-main-0.1.5
[INFO] frobbed toml for fluence-sdk-main-0.1.5 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/fluence-sdk-main/0.1.5/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 fluence-sdk-main-0.1.5 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-0/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/fluence-sdk-main/0.1.5:/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] ece288e3dc9d7e61de309381a551b008762192234b84ec35bf0fbbc76f073902
[INFO] running `"docker" "start" "-a" "ece288e3dc9d7e61de309381a551b008762192234b84ec35bf0fbbc76f073902"`
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling fluence-sdk-main v0.1.5 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]   --> src/lib.rs:22:1
[INFO] [stderr]    |
[INFO] [stderr] 22 | #![feature(allocator_api)]
[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 `fluence-sdk-main`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "ece288e3dc9d7e61de309381a551b008762192234b84ec35bf0fbbc76f073902"`
[INFO] running `"docker" "rm" "-f" "ece288e3dc9d7e61de309381a551b008762192234b84ec35bf0fbbc76f073902"`
[INFO] [stdout] ece288e3dc9d7e61de309381a551b008762192234b84ec35bf0fbbc76f073902