[INFO] updating cached repository saraersson/OS_sem2
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/saraersson/OS_sem2
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/saraersson/OS_sem2" "work/ex/beta-1.38-1/sources/1.37.0/gh/saraersson/OS_sem2"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/saraersson/OS_sem2'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/saraersson/OS_sem2" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/saraersson/OS_sem2"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/saraersson/OS_sem2'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 35d75493f660cb43e3e4f25c701547f80b491f86
[INFO] sha for GitHub repo saraersson/OS_sem2: 35d75493f660cb43e3e4f25c701547f80b491f86
[INFO] validating manifest of saraersson/OS_sem2 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 saraersson/OS_sem2 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 saraersson/OS_sem2
[INFO] finished frobbing saraersson/OS_sem2
[INFO] frobbed toml for saraersson/OS_sem2 written to work/ex/beta-1.38-1/sources/1.37.0/gh/saraersson/OS_sem2/Cargo.toml
[INFO] started frobbing saraersson/OS_sem2
[INFO] finished frobbing saraersson/OS_sem2
[INFO] frobbed toml for saraersson/OS_sem2 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/saraersson/OS_sem2/Cargo.toml
[INFO] crate saraersson/OS_sem2 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 saraersson/OS_sem2 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-4/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/saraersson/OS_sem2:/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] ff887af4ffdcc6122c59886f9d53a41d9f8e892de4f196a9bc85f969a0bb25b0
[INFO] running `"docker" "start" "-a" "ff887af4ffdcc6122c59886f9d53a41d9f8e892de4f196a9bc85f969a0bb25b0"`
[INFO] [stderr]    Compiling blog_os 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: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 stable release channel
[INFO] [stderr]  --> src/lib.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![feature(lang_items)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![feature(unique)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:5:1
[INFO] [stderr]   |
[INFO] [stderr] 5 | #![feature(const_unique_new)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `core::fmt`
[INFO] [stderr]   --> src/vga_buffer.rs:62:5
[INFO] [stderr]    |
[INFO] [stderr] 62 | use core::fmt;
[INFO] [stderr]    |     ^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] error[E0522]: definition of an unknown language item: `panic_fmt`
[INFO] [stderr]   --> src/lib.rs:33:1
[INFO] [stderr]    |
[INFO] [stderr] 33 | #[lang = "panic_fmt"] #[no_mangle] 
[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[E0658]: use of unstable library feature 'ptr_internals': use NonNull instead and consider PhantomData<T> (if you also use #[may_dangle]), Send, and/or Sync
[INFO] [stderr]   --> src/vga_buffer.rs:38:28
[INFO] [stderr]    |
[INFO] [stderr] 38 |           buffer: unsafe { Unique::new_unchecked(0xb8000 as *mut _) },
[INFO] [stderr]    |                            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0658]: use of unstable library feature 'ptr_internals': use NonNull instead and consider PhantomData<T> (if you also use #[may_dangle]), Send, and/or Sync
[INFO] [stderr]   --> src/vga_buffer.rs:61:5
[INFO] [stderr]    |
[INFO] [stderr] 61 | use core::ptr::Unique;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0658]: use of unstable library feature 'ptr_internals': use NonNull instead and consider PhantomData<T> (if you also use #[may_dangle]), Send, and/or Sync
[INFO] [stderr]   --> src/vga_buffer.rs:67:13
[INFO] [stderr]    |
[INFO] [stderr] 67 |     buffer: Unique<Buffer>,
[INFO] [stderr]    |             ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0658]: use of unstable library feature 'ptr_internals'
[INFO] [stderr]   --> src/vga_buffer.rs:38:28
[INFO] [stderr]    |
[INFO] [stderr] 38 |           buffer: unsafe { Unique::new_unchecked(0xb8000 as *mut _) },
[INFO] [stderr]    |                            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0658]: use of unstable library feature 'ptr_internals'
[INFO] [stderr]    --> src/vga_buffer.rs:109:30
[INFO] [stderr]     |
[INFO] [stderr] 109 |         unsafe { self.buffer.as_mut() }
[INFO] [stderr]     |                              ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 11 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0522, E0554, E0658.
[INFO] [stderr] For more information about an error, try `rustc --explain E0522`.
[INFO] [stderr] error: Could not compile `blog_os`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "ff887af4ffdcc6122c59886f9d53a41d9f8e892de4f196a9bc85f969a0bb25b0"`
[INFO] running `"docker" "rm" "-f" "ff887af4ffdcc6122c59886f9d53a41d9f8e892de4f196a9bc85f969a0bb25b0"`
[INFO] [stdout] ff887af4ffdcc6122c59886f9d53a41d9f8e892de4f196a9bc85f969a0bb25b0