[INFO] updating cached repository rajkolli03/min_os_in_rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/rajkolli03/min_os_in_rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/rajkolli03/min_os_in_rust" "work/ex/beta-1.38-1/sources/1.37.0/gh/rajkolli03/min_os_in_rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/rajkolli03/min_os_in_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/rajkolli03/min_os_in_rust" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/rajkolli03/min_os_in_rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/rajkolli03/min_os_in_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 99ba85071aeca8626e5b27aacb6e183dd3764576
[INFO] sha for GitHub repo rajkolli03/min_os_in_rust: 99ba85071aeca8626e5b27aacb6e183dd3764576
[INFO] validating manifest of rajkolli03/min_os_in_rust 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 rajkolli03/min_os_in_rust 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 rajkolli03/min_os_in_rust
[INFO] finished frobbing rajkolli03/min_os_in_rust
[INFO] frobbed toml for rajkolli03/min_os_in_rust written to work/ex/beta-1.38-1/sources/1.37.0/gh/rajkolli03/min_os_in_rust/Cargo.toml
[INFO] started frobbing rajkolli03/min_os_in_rust
[INFO] finished frobbing rajkolli03/min_os_in_rust
[INFO] frobbed toml for rajkolli03/min_os_in_rust written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/rajkolli03/min_os_in_rust/Cargo.toml
[INFO] crate rajkolli03/min_os_in_rust 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] testing rajkolli03/min_os_in_rust against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-7/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/rajkolli03/min_os_in_rust:/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-2019-08-13" "build" "--frozen"`
[INFO] [stdout] 9dc2e69ca30f4038f71f1350a2b61873f313e568bf9351a336913d45e3305b3f
[INFO] running `"docker" "start" "-a" "9dc2e69ca30f4038f71f1350a2b61873f313e568bf9351a336913d45e3305b3f"`
[INFO] [stderr]    Compiling rlibc v1.0.0
[INFO] [stderr]    Compiling min_os_rust v0.1.0 (/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(lang_items)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0522]: definition of an unknown language item: `panic_fmt`
[INFO] [stderr]   --> src/lib.rs:24:1
[INFO] [stderr]    |
[INFO] [stderr] 24 | #[lang = "panic_fmt"] #[no_mangle] pub extern fn panic_fmt() -> ! {loop{}}
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^ definition of unknown language item `panic_fmt`
[INFO] [stderr] 
[INFO] [stderr] error: `#[panic_handler]` function required, but not found
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 3 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0522, E0554.
[INFO] [stderr] For more information about an error, try `rustc --explain E0522`.
[INFO] [stderr] error: Could not compile `min_os_rust`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "9dc2e69ca30f4038f71f1350a2b61873f313e568bf9351a336913d45e3305b3f"`
[INFO] running `"docker" "rm" "-f" "9dc2e69ca30f4038f71f1350a2b61873f313e568bf9351a336913d45e3305b3f"`
[INFO] [stdout] 9dc2e69ca30f4038f71f1350a2b61873f313e568bf9351a336913d45e3305b3f