[INFO] crate metrics 0.2.3 is already in cache
[INFO] extracting crate metrics 0.2.3 into work/ex/pr-56955/sources/master#d99a320cba42f661aebfa1293b7b2ec3603dda75/reg/metrics/0.2.3
[INFO] extracting crate metrics 0.2.3 into work/ex/pr-56955/sources/try#e70472fc501b855c9080f3772432c10fe20b8866/reg/metrics/0.2.3
[INFO] validating manifest of metrics-0.2.3 on toolchain master#d99a320cba42f661aebfa1293b7b2ec3603dda75
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+d99a320cba42f661aebfa1293b7b2ec3603dda75-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of metrics-0.2.3 on toolchain try#e70472fc501b855c9080f3772432c10fe20b8866
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e70472fc501b855c9080f3772432c10fe20b8866-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing metrics-0.2.3
[INFO] finished frobbing metrics-0.2.3
[INFO] frobbed toml for metrics-0.2.3 written to work/ex/pr-56955/sources/master#d99a320cba42f661aebfa1293b7b2ec3603dda75/reg/metrics/0.2.3/Cargo.toml
[INFO] started frobbing metrics-0.2.3
[INFO] finished frobbing metrics-0.2.3
[INFO] frobbed toml for metrics-0.2.3 written to work/ex/pr-56955/sources/try#e70472fc501b855c9080f3772432c10fe20b8866/reg/metrics/0.2.3/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+d99a320cba42f661aebfa1293b7b2ec3603dda75-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e70472fc501b855c9080f3772432c10fe20b8866-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+d99a320cba42f661aebfa1293b7b2ec3603dda75-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e70472fc501b855c9080f3772432c10fe20b8866-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking metrics-0.2.3 against try#e70472fc501b855c9080f3772432c10fe20b8866 for pr-56955
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56955/worker-3/try#e70472fc501b855c9080f3772432c10fe20b8866:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-56955/sources/try#e70472fc501b855c9080f3772432c10fe20b8866/reg/metrics/0.2.3:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+e70472fc501b855c9080f3772432c10fe20b8866-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] ef936eb585c05dfbba24f8a01499d4290edbdceef29b66e46b42a454f2e1627f
[INFO] running `"docker" "start" "-a" "ef936eb585c05dfbba24f8a01499d4290edbdceef29b66e46b42a454f2e1627f"`
[INFO] [stderr]     Checking metrics v0.2.3 (/opt/crater/workdir)
[INFO] [stderr]     Checking iron v0.5.1
[INFO] [stderr] error[E0119]: conflicting implementations of trait `middleware::BeforeMiddleware` for type `std::sync::Arc<_>`:
[INFO] [stderr]    --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/iron-0.5.1/src/middleware/mod.rs:339:1
[INFO] [stderr]     |
[INFO] [stderr] 322 | / impl<F> BeforeMiddleware for F
[INFO] [stderr] 323 | | where F: Send + Sync + 'static + Fn(&mut Request) -> IronResult<()> {
[INFO] [stderr] 324 | |     fn before(&self, req: &mut Request) -> IronResult<()> {
[INFO] [stderr] 325 | |         (*self)(req)
[INFO] [stderr] 326 | |     }
[INFO] [stderr] 327 | | }
[INFO] [stderr]     | |_- first implementation here
[INFO] [stderr] ...
[INFO] [stderr] 339 |   impl<T> BeforeMiddleware for Arc<T> where T: BeforeMiddleware {
[INFO] [stderr]     |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `std::sync::Arc<_>`
[INFO] [stderr]     |
[INFO] [stderr]     = note: downstream crates may implement trait `std::ops::FnOnce<(&mut request::Request<'_, '_>,)>` for type `std::sync::Arc<_>`
[INFO] [stderr]     = note: downstream crates may implement trait `std::ops::Fn<(&mut request::Request<'_, '_>,)>` for type `std::sync::Arc<_>`
[INFO] [stderr] 
[INFO] [stderr] error[E0119]: conflicting implementations of trait `middleware::AfterMiddleware` for type `std::sync::Arc<_>`:
[INFO] [stderr]    --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/iron-0.5.1/src/middleware/mod.rs:366:1
[INFO] [stderr]     |
[INFO] [stderr] 349 | / impl<F> AfterMiddleware for F
[INFO] [stderr] 350 | | where F: Send + Sync + 'static + Fn(&mut Request, Response) -> IronResult<Response> {
[INFO] [stderr] 351 | |     fn after(&self, req: &mut Request, res: Response) -> IronResult<Response> {
[INFO] [stderr] 352 | |         (*self)(req, res)
[INFO] [stderr] 353 | |     }
[INFO] [stderr] 354 | | }
[INFO] [stderr]     | |_- first implementation here
[INFO] [stderr] ...
[INFO] [stderr] 366 |   impl<T> AfterMiddleware for Arc<T> where T: AfterMiddleware {
[INFO] [stderr]     |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `std::sync::Arc<_>`
[INFO] [stderr]     |
[INFO] [stderr]     = note: downstream crates may implement trait `std::ops::FnOnce<(&mut request::Request<'_, '_>, response::Response)>` for type `std::sync::Arc<_>`
[INFO] [stderr]     = note: downstream crates may implement trait `std::ops::Fn<(&mut request::Request<'_, '_>, response::Response)>` for type `std::sync::Arc<_>`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0119`.
[INFO] [stderr] error: Could not compile `iron`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "ef936eb585c05dfbba24f8a01499d4290edbdceef29b66e46b42a454f2e1627f"`
[INFO] running `"docker" "rm" "-f" "ef936eb585c05dfbba24f8a01499d4290edbdceef29b66e46b42a454f2e1627f"`
[INFO] [stdout] ef936eb585c05dfbba24f8a01499d4290edbdceef29b66e46b42a454f2e1627f