[INFO] updating cached repository dropbox/ruba
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/dropbox/ruba
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/dropbox/ruba" "work/ex/beta-1.37-6/sources/1.36.0/gh/dropbox/ruba"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/1.36.0/gh/dropbox/ruba'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/dropbox/ruba" "work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/dropbox/ruba"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/dropbox/ruba'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 60f3e8674f59669f827c2ea59f61c71768cb3b9d
[INFO] sha for GitHub repo dropbox/ruba: 60f3e8674f59669f827c2ea59f61c71768cb3b9d
[INFO] validating manifest of dropbox/ruba on toolchain 1.36.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of dropbox/ruba on toolchain beta-2019-07-23
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing dropbox/ruba
[INFO] finished frobbing dropbox/ruba
[INFO] frobbed toml for dropbox/ruba written to work/ex/beta-1.37-6/sources/1.36.0/gh/dropbox/ruba/Cargo.toml
[INFO] started frobbing dropbox/ruba
[INFO] finished frobbing dropbox/ruba
[INFO] frobbed toml for dropbox/ruba written to work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/dropbox/ruba/Cargo.toml
[INFO] crate dropbox/ruba already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing dropbox/ruba against 1.36.0 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/dropbox/ruba:/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" "+1.36.0" "build" "--frozen"`
[INFO] [stdout] 8ec4d21728d0999f6ac8f8ab946620da06456662154c38299b0c967721da3b69
[INFO] running `"docker" "start" "-a" "8ec4d21728d0999f6ac8f8ab946620da06456662154c38299b0c967721da3b69"`
[INFO] [stderr]    Compiling either v1.4.0
[INFO] [stderr]    Compiling heapsize v0.3.9
[INFO] [stderr]    Compiling seahash v3.0.5
[INFO] [stderr]    Compiling memchr v1.0.2
[INFO] [stderr]    Compiling nix v0.5.1
[INFO] [stderr]    Compiling bincode v0.9.2
[INFO] [stderr]    Compiling serde_json v0.9.10
[INFO] [stderr]    Compiling num-rational v0.1.42
[INFO] [stderr]    Compiling backtrace-sys v0.1.16
[INFO] [stderr]    Compiling nom v3.2.1
[INFO] [stderr]    Compiling csv v0.15.0
[INFO] [stderr]    Compiling backtrace v0.3.5
[INFO] [stderr]    Compiling futures-core v0.2.0-alpha
[INFO] [stderr]    Compiling itertools v0.5.10
[INFO] [stderr]    Compiling futures-channel v0.2.0-alpha
[INFO] [stderr]    Compiling futures-io v0.2.0-alpha
[INFO] [stderr]    Compiling failure v0.1.1
[INFO] [stderr]    Compiling num v0.1.42
[INFO] [stderr]    Compiling futures-sink v0.2.0-alpha
[INFO] [stderr]    Compiling futures-util v0.2.0-alpha
[INFO] [stderr]    Compiling chrono v0.4.0
[INFO] [stderr]    Compiling rustyline v1.0.0
[INFO] [stderr]    Compiling futures-executor v0.2.0-alpha
[INFO] [stderr]    Compiling futures v0.2.0-alpha
[INFO] [stderr]    Compiling ruba v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(fn_traits, integer_atomics, refcell_replace_swap, trait_alias, nll)]
[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 `ruba`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "8ec4d21728d0999f6ac8f8ab946620da06456662154c38299b0c967721da3b69"`
[INFO] running `"docker" "rm" "-f" "8ec4d21728d0999f6ac8f8ab946620da06456662154c38299b0c967721da3b69"`
[INFO] [stdout] 8ec4d21728d0999f6ac8f8ab946620da06456662154c38299b0c967721da3b69