Aug 01 19:33:45.331 INFO checking unsafe_unwrap-0.1.0 against 1.27.2 for lazy_static-1
Aug 01 19:33:45.331 INFO running: cargo +1.27.2 check --frozen --all --all-targets
Aug 01 19:33:45.331 INFO creating container for: cargo +1.27.2 check --frozen --all --all-targets
Aug 01 19:33:45.331 INFO running `"docker" "create" "-v" "/tmp/crater.njXho2VzkCm1:/source:ro,Z" "-v" "/home/ec2-user/crater/./work/local/target-dirs/lazy_static-1/worker-5/1.27.2:/target:rw,Z" "-v" "/home/ec2-user/crater/./work/local/cargo-home:/cargo-home:ro,Z" "-v" "/home/ec2-user/crater/./work/local/rustup-home:/rustup-home:ro,Z" "-v" "/home/ec2-user/crater/./work/local/cargo-home/git:/cargo-home/git:rw,Z" "-e" "USER_ID=500" "-e" "CMD=cargo +1.27.2 check --frozen --all --all-targets" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "crater"`
Aug 01 19:33:45.573 INFO blam! ca14c0465992c68682d4081e46fc93a6833ecb6bf02a6a789d01b339c1356697
Aug 01 19:33:45.575 INFO running `"docker" "start" "-a" "ca14c0465992c68682d4081e46fc93a6833ecb6bf02a6a789d01b339c1356697"`
Aug 01 19:33:46.442 INFO kablam!     Checking unsafe_unwrap v0.1.0 (file:///source)
Aug 01 19:33:46.833 INFO kablam! error[E0554]: #![feature] may not be used on the stable release channel
Aug 01 19:33:46.833 INFO kablam!   --> src/lib.rs:23:19
Aug 01 19:33:46.833 INFO kablam!    |
Aug 01 19:33:46.833 INFO kablam! 23 | #![cfg_attr(test, feature(test))]
Aug 01 19:33:46.833 INFO kablam!    |                   ^^^^^^^^^^^^^^
Aug 01 19:33:46.833 INFO kablam! 
Aug 01 19:33:46.834 INFO kablam! error: aborting due to previous error
Aug 01 19:33:46.834 INFO kablam! 
Aug 01 19:33:46.834 INFO kablam! For more information about this error, try `rustc --explain E0554`.
Aug 01 19:33:46.840 INFO kablam! error: Could not compile `unsafe_unwrap`.
Aug 01 19:33:46.840 INFO kablam! 
Aug 01 19:33:46.840 INFO kablam! To learn more, run the command again with --verbose.
Aug 01 19:33:46.842 INFO kablam! su: No module specific data is present
Aug 01 19:33:47.430 INFO running `"docker" "rm" "-f" "ca14c0465992c68682d4081e46fc93a6833ecb6bf02a6a789d01b339c1356697"`
Aug 01 19:33:47.587 INFO blam! ca14c0465992c68682d4081e46fc93a6833ecb6bf02a6a789d01b339c1356697