Aug 01 23:36:04.989 INFO checking rust-freqdist-0.1.5 against 1.27.2 for lazy_static-1
Aug 01 23:36:04.989 INFO running: cargo +1.27.2 check --frozen --all --all-targets
Aug 01 23:36:04.989 INFO creating container for: cargo +1.27.2 check --frozen --all --all-targets
Aug 01 23:36:04.990 INFO running `"docker" "create" "-v" "/tmp/crater.emotIliQ9NLL:/source:ro,Z" "-v" "/home/ec2-user/crater/./work/local/target-dirs/lazy_static-1/worker-6/1.27.2:/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 23:36:05.212 INFO blam! 1143f896959a607f72253a366d76205a926cc7ee582b0f91c0d412154ab3e9e0
Aug 01 23:36:05.213 INFO running `"docker" "start" "-a" "1143f896959a607f72253a366d76205a926cc7ee582b0f91c0d412154ab3e9e0"`
Aug 01 23:36:06.251 INFO kablam!     Checking rust-freqdist v0.1.5 (file:///source)
Aug 01 23:36:06.960 INFO kablam! error[E0554]: #![feature] may not be used on the stable release channel
Aug 01 23:36:06.961 INFO kablam!   --> src/lib.rs:29:19
Aug 01 23:36:06.961 INFO kablam!    |
Aug 01 23:36:06.961 INFO kablam! 29 | #![cfg_attr(test, feature(test))]
Aug 01 23:36:06.961 INFO kablam!    |                   ^^^^^^^^^^^^^^
Aug 01 23:36:06.961 INFO kablam! 
Aug 01 23:36:06.963 INFO kablam! error: aborting due to previous error
Aug 01 23:36:06.963 INFO kablam! 
Aug 01 23:36:06.963 INFO kablam! For more information about this error, try `rustc --explain E0554`.
Aug 01 23:36:06.971 INFO kablam! error: Could not compile `rust-freqdist`.
Aug 01 23:36:06.971 INFO kablam! warning: build failed, waiting for other jobs to finish...
Aug 01 23:36:07.157 INFO kablam! error: build failed
Aug 01 23:36:07.158 INFO kablam! su: No module specific data is present
Aug 01 23:36:07.819 INFO running `"docker" "rm" "-f" "1143f896959a607f72253a366d76205a926cc7ee582b0f91c0d412154ab3e9e0"`
Aug 01 23:36:07.976 INFO blam! 1143f896959a607f72253a366d76205a926cc7ee582b0f91c0d412154ab3e9e0