[INFO] updating cached repository hello-rust/subscribers
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/hello-rust/subscribers
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/hello-rust/subscribers" "work/ex/beta-1.38-1/sources/1.37.0/gh/hello-rust/subscribers"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/hello-rust/subscribers'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/hello-rust/subscribers" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hello-rust/subscribers"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hello-rust/subscribers'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 2764fc3372671b8c4b58b27d85bc6b45ca224ed6
[INFO] sha for GitHub repo hello-rust/subscribers: 2764fc3372671b8c4b58b27d85bc6b45ca224ed6
[INFO] validating manifest of hello-rust/subscribers 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 hello-rust/subscribers 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 hello-rust/subscribers
[INFO] finished frobbing hello-rust/subscribers
[INFO] frobbed toml for hello-rust/subscribers written to work/ex/beta-1.38-1/sources/1.37.0/gh/hello-rust/subscribers/Cargo.toml
[INFO] started frobbing hello-rust/subscribers
[INFO] finished frobbing hello-rust/subscribers
[INFO] frobbed toml for hello-rust/subscribers written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hello-rust/subscribers/Cargo.toml
[INFO] crate hello-rust/subscribers 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 hello-rust/subscribers 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-4/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/hello-rust/subscribers:/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] bf15eb124fc2114e7a0246063b87961d4192108ddc82e951cc1eead185595496
[INFO] running `"docker" "start" "-a" "bf15eb124fc2114e7a0246063b87961d4192108ddc82e951cc1eead185595496"`
[INFO] [stderr]    Compiling json v0.11.13
[INFO] [stderr]    Compiling encoding_rs v0.8.6
[INFO] [stderr]    Compiling openssl-sys v0.9.35
[INFO] [stderr]    Compiling relay v0.1.1
[INFO] [stderr]    Compiling tokio-service v0.1.0
[INFO] [stderr]    Compiling want v0.0.4
[INFO] [stderr]    Compiling proc-macro2 v0.4.17
[INFO] [stderr]    Compiling clap v2.32.0
[INFO] [stderr]    Compiling serde_json v1.0.26
[INFO] [stderr]    Compiling phf_shared v0.7.23
[INFO] [stderr]    Compiling serde_urlencoded v0.5.3
[INFO] [stderr]    Compiling libflate v0.1.16
[INFO] [stderr]    Compiling phf_generator v0.7.23
[INFO] [stderr]    Compiling phf v0.7.23
[INFO] [stderr]    Compiling quote v0.6.8
[INFO] [stderr]    Compiling phf_codegen v0.7.23
[INFO] [stderr]    Compiling openssl v0.9.24
[INFO] [stderr]    Compiling syn v0.14.9
[INFO] [stderr]    Compiling tokio-core v0.1.17
[INFO] [stderr]    Compiling mime_guess v2.0.0-alpha.6
[INFO] [stderr]    Compiling hyper v0.11.27
[INFO] [stderr]    Compiling native-tls v0.1.5
[INFO] [stderr]    Compiling tokio-tls v0.1.4
[INFO] [stderr]    Compiling synstructure v0.9.0
[INFO] [stderr]    Compiling failure_derive v0.1.2
[INFO] [stderr]    Compiling structopt-derive v0.2.10
[INFO] [stderr]    Compiling failure v0.1.2
[INFO] [stderr]    Compiling hyper-tls v0.1.4
[INFO] [stderr]    Compiling structopt v0.2.10
[INFO] [stderr]    Compiling reqwest v0.8.8
[INFO] [stderr]    Compiling subscribers v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/main.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(try_trait)]
[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 `subscribers`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "bf15eb124fc2114e7a0246063b87961d4192108ddc82e951cc1eead185595496"`
[INFO] running `"docker" "rm" "-f" "bf15eb124fc2114e7a0246063b87961d4192108ddc82e951cc1eead185595496"`
[INFO] [stdout] bf15eb124fc2114e7a0246063b87961d4192108ddc82e951cc1eead185595496