[INFO] updating cached repository nicmr/spren_os
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/nicmr/spren_os
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/nicmr/spren_os" "work/ex/beta-1.38-1/sources/1.37.0/gh/nicmr/spren_os"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/nicmr/spren_os'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/nicmr/spren_os" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/nicmr/spren_os"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/nicmr/spren_os'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 8beab388756cc652bb1cb182732dd7a236f2f58b
[INFO] sha for GitHub repo nicmr/spren_os: 8beab388756cc652bb1cb182732dd7a236f2f58b
[INFO] validating manifest of nicmr/spren_os 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 nicmr/spren_os 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 nicmr/spren_os
[INFO] finished frobbing nicmr/spren_os
[INFO] frobbed toml for nicmr/spren_os written to work/ex/beta-1.38-1/sources/1.37.0/gh/nicmr/spren_os/Cargo.toml
[INFO] started frobbing nicmr/spren_os
[INFO] finished frobbing nicmr/spren_os
[INFO] frobbed toml for nicmr/spren_os written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/nicmr/spren_os/Cargo.toml
[INFO] crate nicmr/spren_os 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 nicmr/spren_os 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-0/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/nicmr/spren_os:/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] 89e13d16a37b82f25175fe39f743393a3435272c8278ab358836b7b5172d8c93
[INFO] running `"docker" "start" "-a" "89e13d16a37b82f25175fe39f743393a3435272c8278ab358836b7b5172d8c93"`
[INFO] [stderr]    Compiling volatile v0.2.4
[INFO] [stderr]    Compiling spren_os v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0557]: feature has been removed
[INFO] [stderr]  --> src/main.rs:1:12
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(panic_implementation)]
[INFO] [stderr]   |            ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr] note: subsumed by `#[panic_handler]`
[INFO] [stderr]  --> src/main.rs:1:12
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(panic_implementation)]
[INFO] [stderr]   |            ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0658]: The attribute `panic_implementation` is currently unknown to the compiler and may have meaning added to it in the future
[INFO] [stderr]   --> src/main.rs:14:3
[INFO] [stderr]    |
[INFO] [stderr] 14 | #[panic_implementation]
[INFO] [stderr]    |   ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: for more information, see https://github.com/rust-lang/rust/issues/29642
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/main.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(panic_implementation)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/main.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![feature(use_extern_macros)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/vga_buffer.rs:83:21
[INFO] [stderr]    |
[INFO] [stderr] 83 |                 0x20...0x7e | b'\n' => self.write_byte(byte),
[INFO] [stderr]    |                     ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(ellipsis_inclusive_range_patterns)] on by default
[INFO] [stderr] 
[INFO] [stderr] error: `#[panic_handler]` function required, but not found
[INFO] [stderr] 
[INFO] [stderr] error: language item required, but not found: `eh_personality`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 6 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0554, E0557, E0658.
[INFO] [stderr] For more information about an error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `spren_os`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "89e13d16a37b82f25175fe39f743393a3435272c8278ab358836b7b5172d8c93"`
[INFO] running `"docker" "rm" "-f" "89e13d16a37b82f25175fe39f743393a3435272c8278ab358836b7b5172d8c93"`
[INFO] [stdout] 89e13d16a37b82f25175fe39f743393a3435272c8278ab358836b7b5172d8c93