Aug 17 10:08:12.866 INFO checking slot-0.2.4 against master#142bb27373126edf8367f526358b6c72ecf1d8df for pr-53426
Aug 17 10:08:12.867 INFO running: cargo +142bb27373126edf8367f526358b6c72ecf1d8df-alt check --frozen --all --all-targets
Aug 17 10:08:12.867 INFO creating container for: cargo +142bb27373126edf8367f526358b6c72ecf1d8df-alt check --frozen --all --all-targets
Aug 17 10:08:12.867 INFO running `"docker" "create" "-v" "/home/ec2-user/crater/./work/local/test-source/worker-5/pr-53426/master#142bb27373126edf8367f526358b6c72ecf1d8df:/source:ro,Z" "-v" "/home/ec2-user/crater/./work/local/target-dirs/pr-53426/worker-5/master#142bb27373126edf8367f526358b6c72ecf1d8df:/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" "-e" "USER_ID=500" "-e" "CMD=cargo +142bb27373126edf8367f526358b6c72ecf1d8df-alt check --frozen --all --all-targets" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "crater"`
Aug 17 10:08:13.124 INFO blam! 31f6cc5e2aa3e4e0270e8a20275bbc1258f50a0592d7600368406c512f6382fd
Aug 17 10:08:13.127 INFO running `"docker" "start" "-a" "31f6cc5e2aa3e4e0270e8a20275bbc1258f50a0592d7600368406c512f6382fd"`
Aug 17 10:08:14.053 INFO kablam!     Checking slot v0.2.4 (file:///source)
Aug 17 10:08:14.404 INFO kablam! error[E0658]: unions in const fn are unstable (see issue #51909)
Aug 17 10:08:14.404 INFO kablam!   --> src/lib.rs:17:18
Aug 17 10:08:14.404 INFO kablam!    |
Aug 17 10:08:14.404 INFO kablam! 17 |         unsafe { U { u: () }.v }
Aug 17 10:08:14.404 INFO kablam!    |                  ^^^^^^^^^^^^^
Aug 17 10:08:14.404 INFO kablam!    |
Aug 17 10:08:14.404 INFO kablam!    = help: add #![feature(const_fn_union)] to the crate attributes to enable
Aug 17 10:08:14.404 INFO kablam! 
Aug 17 10:08:14.406 INFO kablam! error: aborting due to previous error
Aug 17 10:08:14.406 INFO kablam! 
Aug 17 10:08:14.406 INFO kablam! For more information about this error, try `rustc --explain E0658`.
Aug 17 10:08:14.428 INFO kablam! error: Could not compile `slot`.
Aug 17 10:08:14.428 INFO kablam! warning: build failed, waiting for other jobs to finish...
Aug 17 10:08:14.718 INFO kablam! error[E0658]: unions in const fn are unstable (see issue #51909)
Aug 17 10:08:14.718 INFO kablam!   --> src/lib.rs:17:18
Aug 17 10:08:14.718 INFO kablam!    |
Aug 17 10:08:14.718 INFO kablam! 17 |         unsafe { U { u: () }.v }
Aug 17 10:08:14.718 INFO kablam!    |                  ^^^^^^^^^^^^^
Aug 17 10:08:14.718 INFO kablam!    |
Aug 17 10:08:14.718 INFO kablam!    = help: add #![feature(const_fn_union)] to the crate attributes to enable
Aug 17 10:08:14.718 INFO kablam! 
Aug 17 10:08:14.718 INFO kablam! error: aborting due to previous error
Aug 17 10:08:14.718 INFO kablam! 
Aug 17 10:08:14.718 INFO kablam! For more information about this error, try `rustc --explain E0658`.
Aug 17 10:08:14.724 INFO kablam! error: Could not compile `slot`.
Aug 17 10:08:14.724 INFO kablam! 
Aug 17 10:08:14.724 INFO kablam! To learn more, run the command again with --verbose.
Aug 17 10:08:14.726 INFO kablam! su: No module specific data is present
Aug 17 10:08:15.187 INFO running `"docker" "rm" "-f" "31f6cc5e2aa3e4e0270e8a20275bbc1258f50a0592d7600368406c512f6382fd"`
Aug 17 10:08:15.360 INFO blam! 31f6cc5e2aa3e4e0270e8a20275bbc1258f50a0592d7600368406c512f6382fd