Sep 10 20:58:42.808 INFO checking concurrent-hashmap-0.2.2 against master#f50b7758f4dc85dc1c5e38258adaa94213ac6ed1 for pr-54090
Sep 10 20:58:42.808 INFO running: cargo +f50b7758f4dc85dc1c5e38258adaa94213ac6ed1-alt check --frozen --all --all-targets
Sep 10 20:58:42.808 INFO running `"docker" "create" "-v" "/home/ec2-user/crater/./work/local/test-source/worker-7/pr-54090/master#f50b7758f4dc85dc1c5e38258adaa94213ac6ed1:/source:ro,Z" "-v" "/home/ec2-user/crater/./work/local/target-dirs/pr-54090/worker-7/master#f50b7758f4dc85dc1c5e38258adaa94213ac6ed1:/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=1000" "-e" "CMD=cargo +f50b7758f4dc85dc1c5e38258adaa94213ac6ed1-alt check --frozen --all --all-targets" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-m" "2G" "crater"`
Sep 10 20:58:42.987 INFO blam! 147b9e56767e01821d1eb4fe888a885eeea816f3296631f37c64393147ef4d18
Sep 10 20:58:42.989 INFO running `"docker" "start" "-a" "147b9e56767e01821d1eb4fe888a885eeea816f3296631f37c64393147ef4d18"`
Sep 10 20:58:44.202 INFO kablam! usermod: no changes
Sep 10 20:58:44.241 INFO kablam!     Checking spin v0.4.8
Sep 10 20:58:44.372 INFO kablam!     Checking concurrent-hashmap v0.2.2 (file:///source)
Sep 10 20:58:45.710 INFO kablam! error[E0635]: unknown feature `step_by`
Sep 10 20:58:45.710 INFO kablam!  --> examples/wordcount.rs:1:12
Sep 10 20:58:45.710 INFO kablam!   |
Sep 10 20:58:45.710 INFO kablam! 1 | #![feature(step_by)]
Sep 10 20:58:45.710 INFO kablam!   |            ^^^^^^^
Sep 10 20:58:45.710 INFO kablam! 
Sep 10 20:58:45.710 INFO kablam! error: aborting due to previous error
Sep 10 20:58:45.710 INFO kablam! 
Sep 10 20:58:45.710 INFO kablam! For more information about this error, try `rustc --explain E0635`.
Sep 10 20:58:45.718 INFO kablam! error: Could not compile `concurrent-hashmap`.
Sep 10 20:58:45.718 INFO kablam! warning: build failed, waiting for other jobs to finish...
Sep 10 20:58:45.734 INFO kablam! warning: variable does not need to be mutable
Sep 10 20:58:45.734 INFO kablam!    --> src/map.rs:537:13
Sep 10 20:58:45.734 INFO kablam!     |
Sep 10 20:58:45.734 INFO kablam! 537 |         let mut e = map.find_mut(&1).unwrap().get();
Sep 10 20:58:45.734 INFO kablam!     |             ----^
Sep 10 20:58:45.734 INFO kablam!     |             |
Sep 10 20:58:45.734 INFO kablam!     |             help: remove this `mut`
Sep 10 20:58:45.734 INFO kablam!     |
Sep 10 20:58:45.734 INFO kablam!     = note: #[warn(unused_mut)] on by default
Sep 10 20:58:45.734 INFO kablam! 
Sep 10 20:58:46.418 INFO kablam! error: build failed
Sep 10 20:58:46.419 INFO kablam! su: No module specific data is present
Sep 10 20:58:47.114 INFO running `"docker" "rm" "-f" "147b9e56767e01821d1eb4fe888a885eeea816f3296631f37c64393147ef4d18"`
Sep 10 20:58:47.179 INFO blam! 147b9e56767e01821d1eb4fe888a885eeea816f3296631f37c64393147ef4d18