[INFO] crate prefix-map 0.3.1 is already in cache
[INFO] extracting crate prefix-map 0.3.1 into work/ex/beta-1.38-1/sources/1.37.0/reg/prefix-map/0.3.1
[INFO] extracting crate prefix-map 0.3.1 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/prefix-map/0.3.1
[INFO] validating manifest of prefix-map-0.3.1 on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of prefix-map-0.3.1 on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing prefix-map-0.3.1
[INFO] finished frobbing prefix-map-0.3.1
[INFO] frobbed toml for prefix-map-0.3.1 written to work/ex/beta-1.38-1/sources/1.37.0/reg/prefix-map/0.3.1/Cargo.toml
[INFO] started frobbing prefix-map-0.3.1
[INFO] finished frobbing prefix-map-0.3.1
[INFO] frobbed toml for prefix-map-0.3.1 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/prefix-map/0.3.1/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing prefix-map-0.3.1 against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/prefix-map/0.3.1:/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=warn" "-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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] bb8b6f73e5a5011d10e0091133946d4bf0e6226c97f8bc1445e5ec3567b3a843
[INFO] running `"docker" "start" "-a" "bb8b6f73e5a5011d10e0091133946d4bf0e6226c97f8bc1445e5ec3567b3a843"`
[INFO] [stderr]    Compiling prefix-map v0.3.1 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![feature(associated_type_defaults, iter_arith, test)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0271]: type mismatch resolving `<T as std::borrow::ToOwned>::Owned == <[T] as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr]    --> src/prefix.rs:102:22
[INFO] [stderr]     |
[INFO] [stderr] 102 | impl<T: Clone + Ord> ToPrefix for [T] {
[INFO] [stderr]     |                      ^^^^^^^^ expected type parameter, found associated type
[INFO] [stderr]     |
[INFO] [stderr]     = note: expected type `T`
[INFO] [stderr]                found type `<[T] as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr] 
[INFO] [stderr] error[E0277]: the trait bound `<[T] as prefix::ToPrefix>::OwnedItem: std::borrow::Borrow<T>` is not satisfied
[INFO] [stderr]    --> src/prefix.rs:102:22
[INFO] [stderr]     |
[INFO] [stderr] 102 | impl<T: Clone + Ord> ToPrefix for [T] {
[INFO] [stderr]     |                      ^^^^^^^^ the trait `std::borrow::Borrow<T>` is not implemented for `<[T] as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr]     |
[INFO] [stderr]     = help: the following implementations were found:
[INFO] [stderr]               <&T as std::borrow::Borrow<T>>
[INFO] [stderr]               <&mut T as std::borrow::Borrow<T>>
[INFO] [stderr]               <T as std::borrow::Borrow<T>>
[INFO] [stderr] 
[INFO] [stderr] error[E0271]: type mismatch resolving `<std::ffi::OsStr as std::borrow::ToOwned>::Owned == <std::path::Path as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr]    --> src/prefix.rs:131:6
[INFO] [stderr]     |
[INFO] [stderr] 131 | impl ToPrefix for Path {
[INFO] [stderr]     |      ^^^^^^^^ expected struct `std::ffi::OsString`, found associated type
[INFO] [stderr]     |
[INFO] [stderr]     = note: expected type `std::ffi::OsString`
[INFO] [stderr]                found type `<std::path::Path as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr] 
[INFO] [stderr] error[E0277]: the trait bound `<std::path::Path as prefix::ToPrefix>::OwnedItem: std::borrow::Borrow<std::ffi::OsStr>` is not satisfied
[INFO] [stderr]    --> src/prefix.rs:131:6
[INFO] [stderr]     |
[INFO] [stderr] 131 | impl ToPrefix for Path {
[INFO] [stderr]     |      ^^^^^^^^ the trait `std::borrow::Borrow<std::ffi::OsStr>` is not implemented for `<std::path::Path as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr]     |
[INFO] [stderr]     = help: the following implementations were found:
[INFO] [stderr]               <&T as std::borrow::Borrow<T>>
[INFO] [stderr]               <&mut T as std::borrow::Borrow<T>>
[INFO] [stderr]               <T as std::borrow::Borrow<T>>
[INFO] [stderr] 
[INFO] [stderr] error[E0271]: type mismatch resolving `<str as std::borrow::ToOwned>::Owned == <str as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr]    --> src/prefix.rs:164:6
[INFO] [stderr]     |
[INFO] [stderr] 164 | impl ToPrefix for str {
[INFO] [stderr]     |      ^^^^^^^^ expected struct `std::string::String`, found associated type
[INFO] [stderr]     |
[INFO] [stderr]     = note: expected type `std::string::String`
[INFO] [stderr]                found type `<str as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr] 
[INFO] [stderr] error[E0277]: the trait bound `<str as prefix::ToPrefix>::OwnedItem: std::borrow::Borrow<str>` is not satisfied
[INFO] [stderr]    --> src/prefix.rs:164:6
[INFO] [stderr]     |
[INFO] [stderr] 164 | impl ToPrefix for str {
[INFO] [stderr]     |      ^^^^^^^^ the trait `std::borrow::Borrow<str>` is not implemented for `<str as prefix::ToPrefix>::OwnedItem`
[INFO] [stderr]     |
[INFO] [stderr]     = help: the following implementations were found:
[INFO] [stderr]               <&T as std::borrow::Borrow<T>>
[INFO] [stderr]               <&mut T as std::borrow::Borrow<T>>
[INFO] [stderr]               <T as std::borrow::Borrow<T>>
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 7 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0271, E0277, E0554.
[INFO] [stderr] For more information about an error, try `rustc --explain E0271`.
[INFO] [stderr] error: Could not compile `prefix-map`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "bb8b6f73e5a5011d10e0091133946d4bf0e6226c97f8bc1445e5ec3567b3a843"`
[INFO] running `"docker" "rm" "-f" "bb8b6f73e5a5011d10e0091133946d4bf0e6226c97f8bc1445e5ec3567b3a843"`
[INFO] [stdout] bb8b6f73e5a5011d10e0091133946d4bf0e6226c97f8bc1445e5ec3567b3a843