Aug 02 14:00:03.846 INFO checking bk-tree-0.3.0 against 1.27.2 for lazy_static-1
Aug 02 14:00:03.846 INFO running: cargo +1.27.2 check --frozen --all --all-targets
Aug 02 14:00:03.846 INFO creating container for: cargo +1.27.2 check --frozen --all --all-targets
Aug 02 14:00:03.846 INFO running `"docker" "create" "-v" "/tmp/crater.wikafNpye8bD:/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 02 14:00:04.172 INFO blam! 62476e26e2eed22faa239edbc1ab34c533f658bcd99f100e994a40d1b5cda7f6
Aug 02 14:00:04.172 INFO running `"docker" "start" "-a" "62476e26e2eed22faa239edbc1ab34c533f658bcd99f100e994a40d1b5cda7f6"`
Aug 02 14:00:05.117 INFO kablam!     Checking bk-tree v0.3.0 (file:///source)
Aug 02 14:00:07.367 INFO kablam! error[E0554]: #![feature] may not be used on the stable release channel
Aug 02 14:00:07.367 INFO kablam!  --> benches/lib.rs:1:1
Aug 02 14:00:07.367 INFO kablam!   |
Aug 02 14:00:07.367 INFO kablam! 1 | #![feature(test)] extern crate test;
Aug 02 14:00:07.367 INFO kablam!   | ^^^^^^^^^^^^^^^^^
Aug 02 14:00:07.367 INFO kablam! 
Aug 02 14:00:07.367 INFO kablam! error: aborting due to previous error
Aug 02 14:00:07.367 INFO kablam! 
Aug 02 14:00:07.367 INFO kablam! For more information about this error, try `rustc --explain E0554`.
Aug 02 14:00:07.429 INFO kablam! error: Could not compile `bk-tree`.
Aug 02 14:00:07.429 INFO kablam! 
Aug 02 14:00:07.429 INFO kablam! To learn more, run the command again with --verbose.
Aug 02 14:00:07.429 INFO kablam! su: No module specific data is present
Aug 02 14:00:08.113 INFO running `"docker" "rm" "-f" "62476e26e2eed22faa239edbc1ab34c533f658bcd99f100e994a40d1b5cda7f6"`
Aug 02 14:00:08.304 INFO blam! 62476e26e2eed22faa239edbc1ab34c533f658bcd99f100e994a40d1b5cda7f6