[INFO] crate osaka 0.2.10 is already in cache
[INFO] extracting crate osaka 0.2.10 into work/ex/beta-1.38-1/sources/1.37.0/reg/osaka/0.2.10
[INFO] extracting crate osaka 0.2.10 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/osaka/0.2.10
[INFO] validating manifest of osaka-0.2.10 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 osaka-0.2.10 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 osaka-0.2.10
[INFO] finished frobbing osaka-0.2.10
[INFO] frobbed toml for osaka-0.2.10 written to work/ex/beta-1.38-1/sources/1.37.0/reg/osaka/0.2.10/Cargo.toml
[INFO] started frobbing osaka-0.2.10
[INFO] finished frobbing osaka-0.2.10
[INFO] frobbed toml for osaka-0.2.10 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/osaka/0.2.10/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 osaka-0.2.10 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-4/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/osaka/0.2.10:/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] b3fca357875944aecab3871dde76554773e9c0500abd7ce2955f67221d43e455
[INFO] running `"docker" "start" "-a" "b3fca357875944aecab3871dde76554773e9c0500abd7ce2955f67221d43e455"`
[INFO] [stderr]    Compiling osaka-macros v0.2.10
[INFO] [stderr]    Compiling osaka v0.2.10 (/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(generators, generator_trait)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![feature(custom_attribute)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![feature(termination_trait_lib)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `warn`
[INFO] [stderr]   --> src/lib.rs:13:11
[INFO] [stderr]    |
[INFO] [stderr] 13 | use log::{warn, debug};
[INFO] [stderr]    |           ^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/lib.rs:216:16
[INFO] [stderr]     |
[INFO] [stderr] 216 |         f: Box<Future<R>>,
[INFO] [stderr]     |                ^^^^^^^^^ help: use `dyn`: `dyn Future<R>`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(bare_trait_objects)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/lib.rs:307:23
[INFO] [stderr]     |
[INFO] [stderr] 307 |     pub fn new(f: Box<Future<R>>, a: Again) -> Self {
[INFO] [stderr]     |                       ^^^^^^^^^ help: use `dyn`: `dyn Future<R>`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 3 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `osaka`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "b3fca357875944aecab3871dde76554773e9c0500abd7ce2955f67221d43e455"`
[INFO] running `"docker" "rm" "-f" "b3fca357875944aecab3871dde76554773e9c0500abd7ce2955f67221d43e455"`
[INFO] [stdout] b3fca357875944aecab3871dde76554773e9c0500abd7ce2955f67221d43e455