[INFO] updating cached repository Pratyush/snark-tutorial
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/Pratyush/snark-tutorial
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/Pratyush/snark-tutorial" "work/ex/beta-1.38-1/sources/1.37.0/gh/Pratyush/snark-tutorial"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/Pratyush/snark-tutorial'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/Pratyush/snark-tutorial" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Pratyush/snark-tutorial"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Pratyush/snark-tutorial'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 72d0f74366e9d11576f8f6a546b40040ca0d55a3
[INFO] sha for GitHub repo Pratyush/snark-tutorial: 72d0f74366e9d11576f8f6a546b40040ca0d55a3
[INFO] validating manifest of Pratyush/snark-tutorial 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 Pratyush/snark-tutorial 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 Pratyush/snark-tutorial
[INFO] finished frobbing Pratyush/snark-tutorial
[INFO] frobbed toml for Pratyush/snark-tutorial written to work/ex/beta-1.38-1/sources/1.37.0/gh/Pratyush/snark-tutorial/Cargo.toml
[INFO] started frobbing Pratyush/snark-tutorial
[INFO] finished frobbing Pratyush/snark-tutorial
[INFO] frobbed toml for Pratyush/snark-tutorial written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Pratyush/snark-tutorial/Cargo.toml
[INFO] crate Pratyush/snark-tutorial already has a lockfile, it will not be regenerated
[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 Pratyush/snark-tutorial 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/gh/Pratyush/snark-tutorial:/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] 471227f18e3fec0705870d0f713b7c0f230c65be3ce3ffa2bf3fcd6ee970ef1a
[INFO] running `"docker" "start" "-a" "471227f18e3fec0705870d0f713b7c0f230c65be3ce3ffa2bf3fcd6ee970ef1a"`
[INFO] [stderr]    Compiling bench-utils v0.1.0 (https://github.com/scipr-lab/zexe#0685bd1b)
[INFO] [stderr]    Compiling rand_derive v0.3.1
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling rayon-core v1.5.0
[INFO] [stderr]    Compiling rayon v1.1.0
[INFO] [stderr]    Compiling algebra v0.1.0 (https://github.com/scipr-lab/zexe#0685bd1b)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]   --> /opt/crater/cargo-home/git/checkouts/zexe-f74c42809fa6cfe1/0685bd1/algebra/src/lib.rs:35:1
[INFO] [stderr]    |
[INFO] [stderr] 35 | #![feature(const_fn)]
[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 `algebra`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "471227f18e3fec0705870d0f713b7c0f230c65be3ce3ffa2bf3fcd6ee970ef1a"`
[INFO] running `"docker" "rm" "-f" "471227f18e3fec0705870d0f713b7c0f230c65be3ce3ffa2bf3fcd6ee970ef1a"`
[INFO] [stdout] 471227f18e3fec0705870d0f713b7c0f230c65be3ce3ffa2bf3fcd6ee970ef1a