[INFO] crate buddy_system_allocator 0.3.5 is already in cache
[INFO] extracting crate buddy_system_allocator 0.3.5 into work/ex/beta-1.37-6/sources/1.36.0/reg/buddy_system_allocator/0.3.5
[INFO] extracting crate buddy_system_allocator 0.3.5 into work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/buddy_system_allocator/0.3.5
[INFO] validating manifest of buddy_system_allocator-0.3.5 on toolchain 1.36.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of buddy_system_allocator-0.3.5 on toolchain beta-2019-07-23
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing buddy_system_allocator-0.3.5
[INFO] finished frobbing buddy_system_allocator-0.3.5
[INFO] frobbed toml for buddy_system_allocator-0.3.5 written to work/ex/beta-1.37-6/sources/1.36.0/reg/buddy_system_allocator/0.3.5/Cargo.toml
[INFO] started frobbing buddy_system_allocator-0.3.5
[INFO] finished frobbing buddy_system_allocator-0.3.5
[INFO] frobbed toml for buddy_system_allocator-0.3.5 written to work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/buddy_system_allocator/0.3.5/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing buddy_system_allocator-0.3.5 against beta-2019-07-23 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-4/beta-2019-07-23:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/buddy_system_allocator/0.3.5:/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" "+beta-2019-07-23" "build" "--frozen"`
[INFO] [stdout] 10f2a10f759a1d068e1bdde03a1feb45cc2cb74d3f1b5c5015ba9f53f2cc9a0c
[INFO] running `"docker" "start" "-a" "10f2a10f759a1d068e1bdde03a1feb45cc2cb74d3f1b5c5015ba9f53f2cc9a0c"`
[INFO] [stderr]    Compiling buddy_system_allocator v0.3.5 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the beta release channel
[INFO] [stderr]  --> src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(const_fn)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the beta release channel
[INFO] [stderr]  --> src/lib.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![feature(alloc, allocator_api)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `alloc::boxed::Box`
[INFO] [stderr]    --> src/lib.rs:267:5
[INFO] [stderr]     |
[INFO] [stderr] 267 | use alloc::boxed::Box;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `buddy_system_allocator`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "10f2a10f759a1d068e1bdde03a1feb45cc2cb74d3f1b5c5015ba9f53f2cc9a0c"`
[INFO] running `"docker" "rm" "-f" "10f2a10f759a1d068e1bdde03a1feb45cc2cb74d3f1b5c5015ba9f53f2cc9a0c"`
[INFO] [stdout] 10f2a10f759a1d068e1bdde03a1feb45cc2cb74d3f1b5c5015ba9f53f2cc9a0c