[INFO] updating cached repository https://github.com/foldu/pickwp
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] [stderr] From https://github.com/foldu/pickwp
[INFO] [stderr]  * [new branch]      dependabot/cargo/serde_json-1.0.41 -> dependabot/cargo/serde_json-1.0.41
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 384e95033780d2d40c35238551214054edb9972a
[INFO] testing foldu/pickwp against beta-2019-09-28 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffoldu%2Fpickwp" "work/builds/worker-7/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/foldu/pickwp on toolchain beta-2019-09-28
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/foldu/pickwp
[INFO] finished tweaking git repo https://github.com/foldu/pickwp
[INFO] tweaked toml for git repo https://github.com/foldu/pickwp written to work/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/foldu/pickwp already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-7/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2019-09-28" "build" "--frozen"`
[INFO] [stdout] 0a55d5038d31d9bd6779c007cdd0aa8e035adf2f3dbb83459b65d7c101ea4f1f
[INFO] running `"docker" "start" "-a" "0a55d5038d31d9bd6779c007cdd0aa8e035adf2f3dbb83459b65d7c101ea4f1f"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.61
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling proc-macro2 v1.0.1
[INFO] [stderr]    Compiling spin v0.5.2
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling proc-macro-nested v0.1.3
[INFO] [stderr]    Compiling pin-utils v0.1.0-alpha.4
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling strsim v0.9.2
[INFO] [stderr]    Compiling arc-swap v0.4.2
[INFO] [stderr]    Compiling doc-comment v0.3.1
[INFO] [stderr]    Compiling half v1.3.0
[INFO] [stderr]    Compiling once_cell v0.2.7
[INFO] [stderr]    Compiling slotmap v0.4.0
[INFO] [stderr]    Compiling strum v0.16.0
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slotmap-0.4.0/src/lib.rs:4:35
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![cfg_attr(feature = "unstable", feature(untagged_unions, try_reserve))]
[INFO] [stderr]   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]    Compiling phf_shared v0.7.24
[INFO] [stderr]    Compiling lazy_static v1.3.0
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `slotmap`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "0a55d5038d31d9bd6779c007cdd0aa8e035adf2f3dbb83459b65d7c101ea4f1f"`
[INFO] running `"docker" "rm" "-f" "0a55d5038d31d9bd6779c007cdd0aa8e035adf2f3dbb83459b65d7c101ea4f1f"`
[INFO] [stdout] 0a55d5038d31d9bd6779c007cdd0aa8e035adf2f3dbb83459b65d7c101ea4f1f