[INFO] crate heim-disk 0.0.5 is already in cache
[INFO] extracting crate heim-disk 0.0.5 into work/ex/beta-1.38-1/sources/1.37.0/reg/heim-disk/0.0.5
[INFO] extracting crate heim-disk 0.0.5 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/heim-disk/0.0.5
[INFO] validating manifest of heim-disk-0.0.5 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 heim-disk-0.0.5 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 heim-disk-0.0.5
[INFO] finished frobbing heim-disk-0.0.5
[INFO] frobbed toml for heim-disk-0.0.5 written to work/ex/beta-1.38-1/sources/1.37.0/reg/heim-disk/0.0.5/Cargo.toml
[INFO] started frobbing heim-disk-0.0.5
[INFO] finished frobbing heim-disk-0.0.5
[INFO] frobbed toml for heim-disk-0.0.5 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/heim-disk/0.0.5/Cargo.toml
[INFO] crate heim-disk-0.0.5 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 heim-disk-0.0.5 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/reg/heim-disk/0.0.5:/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] 06cb80862d833a97c7e32a7b8716e8aafa66dfc051d1cf0b23f7396f01edc4b1
[INFO] running `"docker" "start" "-a" "06cb80862d833a97c7e32a7b8716e8aafa66dfc051d1cf0b23f7396f01edc4b1"`
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling syn v0.15.42
[INFO] [stderr]    Compiling heim-common v0.0.5
[INFO] [stderr]    Compiling num_cpus v1.10.1
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling nix v0.14.1
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling futures-executor-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling futures-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling heim-derive v0.0.5
[INFO] [stderr]    Compiling heim-disk v0.0.5 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 38.65s
[INFO] running `"docker" "inspect" "06cb80862d833a97c7e32a7b8716e8aafa66dfc051d1cf0b23f7396f01edc4b1"`
[INFO] running `"docker" "rm" "-f" "06cb80862d833a97c7e32a7b8716e8aafa66dfc051d1cf0b23f7396f01edc4b1"`
[INFO] [stdout] 06cb80862d833a97c7e32a7b8716e8aafa66dfc051d1cf0b23f7396f01edc4b1
[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/reg/heim-disk/0.0.5:/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" "test" "--frozen" "--no-run"`
[INFO] [stdout] b3054e733c1562fa19633bdeba0843df061fde3183f3afbb5ae04b51d7456fb8
[INFO] running `"docker" "start" "-a" "b3054e733c1562fa19633bdeba0843df061fde3183f3afbb5ae04b51d7456fb8"`
[INFO] [stderr]    Compiling autocfg v0.1.5
[INFO] [stderr]    Compiling serde v1.0.97
[INFO] [stderr]    Compiling async-ready v3.0.0
[INFO] [stderr]    Compiling async-datagram v3.0.0
[INFO] [stderr]    Compiling async-datagram v2.2.0
[INFO] [stderr]    Compiling crossbeam-utils v0.6.5
[INFO] [stderr]    Compiling regex-syntax v0.6.10
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling net2 v0.2.33
[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/async-datagram-2.2.0/src/lib.rs:43:1
[INFO] [stderr]    |
[INFO] [stderr] 43 | #![feature(futures_api)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr]    Compiling iovec v0.1.2
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `async-datagram`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "b3054e733c1562fa19633bdeba0843df061fde3183f3afbb5ae04b51d7456fb8"`
[INFO] running `"docker" "rm" "-f" "b3054e733c1562fa19633bdeba0843df061fde3183f3afbb5ae04b51d7456fb8"`
[INFO] [stdout] b3054e733c1562fa19633bdeba0843df061fde3183f3afbb5ae04b51d7456fb8