[INFO] updating cached repository WireGuard/wireguard-rs
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/WireGuard/wireguard-rs
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/WireGuard/wireguard-rs" "work/ex/beta-1.38-1/sources/1.37.0/gh/WireGuard/wireguard-rs"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/WireGuard/wireguard-rs'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/WireGuard/wireguard-rs" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/WireGuard/wireguard-rs"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/WireGuard/wireguard-rs'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] a7a2e52315718f21e4bf1e14bffeebd6e300699d
[INFO] sha for GitHub repo WireGuard/wireguard-rs: a7a2e52315718f21e4bf1e14bffeebd6e300699d
[INFO] validating manifest of WireGuard/wireguard-rs 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 WireGuard/wireguard-rs 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 WireGuard/wireguard-rs
[INFO] finished frobbing WireGuard/wireguard-rs
[INFO] frobbed toml for WireGuard/wireguard-rs written to work/ex/beta-1.38-1/sources/1.37.0/gh/WireGuard/wireguard-rs/Cargo.toml
[INFO] started frobbing WireGuard/wireguard-rs
[INFO] finished frobbing WireGuard/wireguard-rs
[INFO] frobbed toml for WireGuard/wireguard-rs written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/WireGuard/wireguard-rs/Cargo.toml
[INFO] crate WireGuard/wireguard-rs 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 WireGuard/wireguard-rs 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-4/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/WireGuard/wireguard-rs:/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] c16f7a0679808599595cff8649b03f0aed761bef51de246b49ac3c6134d291ca
[INFO] running `"docker" "start" "-a" "c16f7a0679808599595cff8649b03f0aed761bef51de246b49ac3c6134d291ca"`
[INFO] [stderr]    Compiling cc v1.0.17
[INFO] [stderr]    Compiling lazy_static v1.0.1
[INFO] [stderr]    Compiling subtle v0.6.2
[INFO] [stderr]    Compiling rustc-demangle v0.1.8
[INFO] [stderr]    Compiling slab v0.1.3
[INFO] [stderr]    Compiling subtle v0.5.1
[INFO] [stderr]    Compiling scoped-tls v0.1.2
[INFO] [stderr]    Compiling nix v0.11.0-pre (https://github.com/mcginty/nix?branch=ipv6-pktinfo#d5c3de15)
[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/subtle-0.6.2/src/lib.rs:13:34
[INFO] [stderr]    |
[INFO] [stderr] 13 | #![cfg_attr(feature = "nightly", feature(i128_type))]
[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/subtle-0.6.2/src/lib.rs:14:34
[INFO] [stderr]    |
[INFO] [stderr] 14 | #![cfg_attr(feature = "nightly", feature(test))]
[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/subtle-0.6.2/src/lib.rs:16:34
[INFO] [stderr]    |
[INFO] [stderr] 16 | #![cfg_attr(feature = "nightly", feature(external_doc))]
[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/subtle-0.6.2/src/lib.rs:18:34
[INFO] [stderr]    |
[INFO] [stderr] 18 | #![cfg_attr(feature = "nightly", feature(asm))]
[INFO] [stderr]    |                                  ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]    Compiling same-file v1.0.2
[INFO] [stderr]    Compiling untrusted v0.6.1
[INFO] [stderr] error: aborting due to 4 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `subtle`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "c16f7a0679808599595cff8649b03f0aed761bef51de246b49ac3c6134d291ca"`
[INFO] running `"docker" "rm" "-f" "c16f7a0679808599595cff8649b03f0aed761bef51de246b49ac3c6134d291ca"`
[INFO] [stdout] c16f7a0679808599595cff8649b03f0aed761bef51de246b49ac3c6134d291ca