[INFO] updating cached repository archer884/shuffle
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/archer884/shuffle
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/archer884/shuffle" "work/ex/beta-1.38-1/sources/1.37.0/gh/archer884/shuffle"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/archer884/shuffle'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/archer884/shuffle" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/archer884/shuffle"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/archer884/shuffle'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] d16eeb8e3c8a6ebe3f44633c920986facd6c2cd3
[INFO] sha for GitHub repo archer884/shuffle: d16eeb8e3c8a6ebe3f44633c920986facd6c2cd3
[INFO] validating manifest of archer884/shuffle 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 archer884/shuffle 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 archer884/shuffle
[INFO] finished frobbing archer884/shuffle
[INFO] frobbed toml for archer884/shuffle written to work/ex/beta-1.38-1/sources/1.37.0/gh/archer884/shuffle/Cargo.toml
[INFO] started frobbing archer884/shuffle
[INFO] finished frobbing archer884/shuffle
[INFO] frobbed toml for archer884/shuffle written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/archer884/shuffle/Cargo.toml
[INFO] crate archer884/shuffle 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] [stderr] error: the lock file /mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/archer884/shuffle/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] the lockfile is outdated, regenerating it
[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 archer884/shuffle against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-2/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/archer884/shuffle:/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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] daa3f5e6a0ab56febd34e219ff47e6856cc0f7bd4ef3f570012590c13a01d08d
[INFO] running `"docker" "start" "-a" "daa3f5e6a0ab56febd34e219ff47e6856cc0f7bd4ef3f570012590c13a01d08d"`
[INFO] [stderr]    Compiling shuffle v0.0.1 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/nshuffle.rs:42:1
[INFO] [stderr]    |
[INFO] [stderr] 42 | #![feature(collections)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `push_all` found for type `std::vec::Vec<_>` in the current scope
[INFO] [stderr]   --> src/nshuffle.rs:49:9
[INFO] [stderr]    |
[INFO] [stderr] 49 |     vec.push_all(s);
[INFO] [stderr]    |         ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `shuffle` found for type `&mut R` in the current scope
[INFO] [stderr]   --> src/nshuffle.rs:52:11
[INFO] [stderr]    |
[INFO] [stderr] 52 |         r.shuffle(&mut vec);
[INFO] [stderr]    |           ^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr]    = note: the following trait defines an item `shuffle`, perhaps you need to implement it:
[INFO] [stderr]            candidate #1: `rand::prelude::SliceRandom`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `push_all` found for type `std::vec::Vec<_>` in the current scope
[INFO] [stderr]   --> src/nshuffle.rs:59:9
[INFO] [stderr]    |
[INFO] [stderr] 59 |     vec.push_all(s);
[INFO] [stderr]    |         ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `shuffle` found for type `&mut R` in the current scope
[INFO] [stderr]   --> src/nshuffle.rs:62:11
[INFO] [stderr]    |
[INFO] [stderr] 62 |         r.shuffle(&mut vec)
[INFO] [stderr]    |           ^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr]    = note: the following trait defines an item `shuffle`, perhaps you need to implement it:
[INFO] [stderr]            candidate #1: `rand::prelude::SliceRandom`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 5 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0554, E0599.
[INFO] [stderr] For more information about an error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `shuffle`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "daa3f5e6a0ab56febd34e219ff47e6856cc0f7bd4ef3f570012590c13a01d08d"`
[INFO] running `"docker" "rm" "-f" "daa3f5e6a0ab56febd34e219ff47e6856cc0f7bd4ef3f570012590c13a01d08d"`
[INFO] [stdout] daa3f5e6a0ab56febd34e219ff47e6856cc0f7bd4ef3f570012590c13a01d08d