[INFO] crate mmime 0.1.0 is already in cache
[INFO] extracting crate mmime 0.1.0 into work/ex/beta-1.38-1/sources/1.37.0/reg/mmime/0.1.0
[INFO] extracting crate mmime 0.1.0 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/mmime/0.1.0
[INFO] validating manifest of mmime-0.1.0 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 mmime-0.1.0 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 mmime-0.1.0
[INFO] finished frobbing mmime-0.1.0
[INFO] frobbed toml for mmime-0.1.0 written to work/ex/beta-1.38-1/sources/1.37.0/reg/mmime/0.1.0/Cargo.toml
[INFO] started frobbing mmime-0.1.0
[INFO] finished frobbing mmime-0.1.0
[INFO] frobbed toml for mmime-0.1.0 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/mmime/0.1.0/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing mmime-0.1.0 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/reg/mmime/0.1.0:/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] a32271099321aa20a2e7af7bc1f1c0616a8315f0ead28ea22b2224c2b3806c8c
[INFO] running `"docker" "start" "-a" "a32271099321aa20a2e7af7bc1f1c0616a8315f0ead28ea22b2224c2b3806c8c"`
[INFO] [stderr]    Compiling charset v0.1.2
[INFO] [stderr]    Compiling mmime v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:10:1
[INFO] [stderr]    |
[INFO] [stderr] 10 | #![feature(extern_types)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:11:1
[INFO] [stderr]    |
[INFO] [stderr] 11 | #![feature(const_raw_ptr_to_usize_cast)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:12:1
[INFO] [stderr]    |
[INFO] [stderr] 12 | #![feature(ptr_wrapping_offset_from)]
[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 `mmime`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "a32271099321aa20a2e7af7bc1f1c0616a8315f0ead28ea22b2224c2b3806c8c"`
[INFO] running `"docker" "rm" "-f" "a32271099321aa20a2e7af7bc1f1c0616a8315f0ead28ea22b2224c2b3806c8c"`
[INFO] [stdout] a32271099321aa20a2e7af7bc1f1c0616a8315f0ead28ea22b2224c2b3806c8c