[INFO] updating cached repository djudd/human-name-rb
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/djudd/human-name-rb
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/djudd/human-name-rb" "work/ex/beta-1.38-1/sources/1.37.0/gh/djudd/human-name-rb"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/djudd/human-name-rb'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/djudd/human-name-rb" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/djudd/human-name-rb"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/djudd/human-name-rb'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 420e24e115b2bd6d102e073c131725ae55d215dc
[INFO] sha for GitHub repo djudd/human-name-rb: 420e24e115b2bd6d102e073c131725ae55d215dc
[INFO] validating manifest of djudd/human-name-rb 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 djudd/human-name-rb 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 djudd/human-name-rb
[INFO] finished frobbing djudd/human-name-rb
[INFO] frobbed toml for djudd/human-name-rb written to work/ex/beta-1.38-1/sources/1.37.0/gh/djudd/human-name-rb/Cargo.toml
[INFO] started frobbing djudd/human-name-rb
[INFO] finished frobbing djudd/human-name-rb
[INFO] frobbed toml for djudd/human-name-rb written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/djudd/human-name-rb/Cargo.toml
[INFO] crate djudd/human-name-rb 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 djudd/human-name-rb 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/djudd/human-name-rb:/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] c08919b63f50a6dd5d914f7a7cafb7e19806a5f4513089214c0048539601c0cc
[INFO] running `"docker" "start" "-a" "c08919b63f50a6dd5d914f7a7cafb7e19806a5f4513089214c0048539601c0cc"`
[INFO] [stderr]    Compiling libcruby-sys v0.6.4
[INFO] [stderr]    Compiling cstr-macro v0.1.0
[INFO] [stderr]    Compiling cslice v0.3.0
[INFO] [stderr]    Compiling smallvec v0.6.8
[INFO] [stderr]    Compiling rand_os v0.1.1
[INFO] [stderr]    Compiling syn v0.15.26
[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/smallvec-0.6.8/lib.rs:33:32
[INFO] [stderr]    |
[INFO] [stderr] 33 | #![cfg_attr(feature = "union", feature(untagged_unions))]
[INFO] [stderr]    |                                ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]    Compiling rand v0.6.4
[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 `smallvec`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "c08919b63f50a6dd5d914f7a7cafb7e19806a5f4513089214c0048539601c0cc"`
[INFO] running `"docker" "rm" "-f" "c08919b63f50a6dd5d914f7a7cafb7e19806a5f4513089214c0048539601c0cc"`
[INFO] [stdout] c08919b63f50a6dd5d914f7a7cafb7e19806a5f4513089214c0048539601c0cc