[INFO] updating cached repository hamadu/hamos
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/hamadu/hamos
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/hamadu/hamos" "work/ex/beta-1.38-1/sources/1.37.0/gh/hamadu/hamos"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/hamadu/hamos'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/hamadu/hamos" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hamadu/hamos"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hamadu/hamos'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 7b8f8d2ddbeaabff4eafbe1e4dd9463b0da9065c
[INFO] sha for GitHub repo hamadu/hamos: 7b8f8d2ddbeaabff4eafbe1e4dd9463b0da9065c
[INFO] validating manifest of hamadu/hamos 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 hamadu/hamos 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 hamadu/hamos
[INFO] finished frobbing hamadu/hamos
[INFO] frobbed toml for hamadu/hamos written to work/ex/beta-1.38-1/sources/1.37.0/gh/hamadu/hamos/Cargo.toml
[INFO] started frobbing hamadu/hamos
[INFO] finished frobbing hamadu/hamos
[INFO] frobbed toml for hamadu/hamos written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hamadu/hamos/Cargo.toml
[INFO] crate hamadu/hamos 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 hamadu/hamos 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-2/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/hamadu/hamos:/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] 84977fe5502efe2a3701384b53f80c4967de48cdeabfc15a7bd85b7d84b7c8e0
[INFO] running `"docker" "start" "-a" "84977fe5502efe2a3701384b53f80c4967de48cdeabfc15a7bd85b7d84b7c8e0"`
[INFO] [stderr]    Compiling spin v0.4.6
[INFO] [stderr]    Compiling x86_64 v0.1.2
[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-0.4.6/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-0.4.6/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-0.4.6/src/lib.rs:8:35
[INFO] [stderr]   |
[INFO] [stderr] 8 | #![cfg_attr(feature = "const_fn", feature(const_fn, const_unsafe_cell_new, const_atomic_usize_new))]
[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] error: Could not compile `spin`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[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/x86_64-0.1.2/src/lib.rs:8:1
[INFO] [stderr]   |
[INFO] [stderr] 8 | #![feature(const_fn)]
[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/x86_64-0.1.2/src/lib.rs:9:1
[INFO] [stderr]   |
[INFO] [stderr] 9 | #![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/x86_64-0.1.2/src/lib.rs:10:1
[INFO] [stderr]    |
[INFO] [stderr] 10 | #![feature(associated_consts)]
[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/x86_64-0.1.2/src/lib.rs:11:1
[INFO] [stderr]    |
[INFO] [stderr] 11 | #![feature(abi_x86_interrupt)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[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 `x86_64`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "84977fe5502efe2a3701384b53f80c4967de48cdeabfc15a7bd85b7d84b7c8e0"`
[INFO] running `"docker" "rm" "-f" "84977fe5502efe2a3701384b53f80c4967de48cdeabfc15a7bd85b7d84b7c8e0"`
[INFO] [stdout] 84977fe5502efe2a3701384b53f80c4967de48cdeabfc15a7bd85b7d84b7c8e0