[INFO] updating cached repository arthurprs/floki
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/arthurprs/floki
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/arthurprs/floki" "work/ex/beta-1.38-1/sources/1.37.0/gh/arthurprs/floki"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/arthurprs/floki'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/arthurprs/floki" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/arthurprs/floki"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/arthurprs/floki'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 8758b9dd276ca25abf7c970c3196e3b230a061d9
[INFO] sha for GitHub repo arthurprs/floki: 8758b9dd276ca25abf7c970c3196e3b230a061d9
[INFO] validating manifest of arthurprs/floki 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 arthurprs/floki 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 arthurprs/floki
[INFO] finished frobbing arthurprs/floki
[INFO] frobbed toml for arthurprs/floki written to work/ex/beta-1.38-1/sources/1.37.0/gh/arthurprs/floki/Cargo.toml
[INFO] started frobbing arthurprs/floki
[INFO] finished frobbing arthurprs/floki
[INFO] frobbed toml for arthurprs/floki written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/arthurprs/floki/Cargo.toml
[INFO] crate arthurprs/floki already has a lockfile, it will not be regenerated
[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 arthurprs/floki 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-5/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/arthurprs/floki:/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] 1fc6c2f94249a85df287381fd895335a73dbe614bbf7f0050d78fc92b9bd466a
[INFO] running `"docker" "start" "-a" "1fc6c2f94249a85df287381fd895335a73dbe614bbf7f0050d78fc92b9bd466a"`
[INFO] [stderr]    Compiling winapi-build v0.1.1
[INFO] [stderr]    Compiling libc v0.2.23
[INFO] [stderr]    Compiling void v1.0.2
[INFO] [stderr]    Compiling winapi v0.2.8
[INFO] [stderr]    Compiling cfg-if v0.1.0
[INFO] [stderr]    Compiling encoding_index_tests v0.1.4
[INFO] [stderr]    Compiling bitflags v0.4.0
[INFO] [stderr]    Compiling utf8-ranges v1.0.0
[INFO] [stderr]    Compiling mac v0.1.1
[INFO] [stderr]    Compiling regex-syntax v0.4.1
[INFO] [stderr]    Compiling threadpool v1.3.2
[INFO] [stderr]    Compiling bytes v0.3.0
[INFO] [stderr]    Compiling serde v1.0.8
[INFO] [stderr]    Compiling slab v0.1.3
[INFO] [stderr]    Compiling bitflags v0.7.0
[INFO] [stderr]    Compiling log v0.3.8
[INFO] [stderr]    Compiling fnv v1.0.5
[INFO] [stderr]    Compiling spin v0.4.5
[INFO] [stderr]    Compiling linked-hash-map v0.4.2
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/spin-0.4.5/src/lib.rs:6:30
[INFO] [stderr]   |
[INFO] [stderr] 6 | #![cfg_attr(feature = "asm", feature(asm))]
[INFO] [stderr]   |                              ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/spin-0.4.5/src/lib.rs:7:42
[INFO] [stderr]   |
[INFO] [stderr] 7 | #![cfg_attr(feature = "core_intrinsics", feature(core_intrinsics))]
[INFO] [stderr]   |                                          ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/spin-0.4.5/src/lib.rs:8:35
[INFO] [stderr]   |
[INFO] [stderr] 8 | #![cfg_attr(feature = "const_fn", feature(const_fn))]
[INFO] [stderr]   |                                   ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 3 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr]    Compiling rustc-serialize v0.3.24
[INFO] [stderr] error: Could not compile `spin`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "1fc6c2f94249a85df287381fd895335a73dbe614bbf7f0050d78fc92b9bd466a"`
[INFO] running `"docker" "rm" "-f" "1fc6c2f94249a85df287381fd895335a73dbe614bbf7f0050d78fc92b9bd466a"`
[INFO] [stdout] 1fc6c2f94249a85df287381fd895335a73dbe614bbf7f0050d78fc92b9bd466a