[INFO] cloning repository https://github.com/mattmacleod/kern
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mattmacleod/kern" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmattmacleod%2Fkern", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmattmacleod%2Fkern'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 704ca2bc73d8bc568f7f44b6a67d61976c8612da
[INFO] testing mattmacleod/kern against master#a77da2d454e6caa227a85b16410b95f93495e7e0 for pr-91031
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmattmacleod%2Fkern" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mattmacleod/kern on toolchain a77da2d454e6caa227a85b16410b95f93495e7e0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mattmacleod/kern
[INFO] finished tweaking git repo https://github.com/mattmacleod/kern
[INFO] tweaked toml for git repo https://github.com/mattmacleod/kern written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/mattmacleod/kern already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 016b7fe05b514722a51eee45292896daf55c7bcd1d82a97cbd75a01e968880e5
[INFO] running `Command { std: "docker" "start" "-a" "016b7fe05b514722a51eee45292896daf55c7bcd1d82a97cbd75a01e968880e5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "016b7fe05b514722a51eee45292896daf55c7bcd1d82a97cbd75a01e968880e5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "016b7fe05b514722a51eee45292896daf55c7bcd1d82a97cbd75a01e968880e5", kill_on_drop: false }`
[INFO] [stdout] 016b7fe05b514722a51eee45292896daf55c7bcd1d82a97cbd75a01e968880e5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0a38610fcaec03baad00a36f222013546b25c8de0ced91a4d919df9021db8cc4
[INFO] running `Command { std: "docker" "start" "-a" "0a38610fcaec03baad00a36f222013546b25c8de0ced91a4d919df9021db8cc4", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rlibc v0.1.4
[INFO] [stderr]    Compiling kern v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:3:29
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(lang_items, asm, const_fn, collections)]
[INFO] [stdout]   |                             ^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: split into finer-grained feature gates
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find macro `format` in this scope
[INFO] [stdout]   --> src/lib.rs:20:13
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let s = format!("{}", res);
[INFO] [stdout]    |             ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `core::fmt::Display`
[INFO] [stdout]  --> src/lib.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use core::fmt::Display;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `core::fmt::Formatter`
[INFO] [stdout]  --> src/lib.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use core::fmt::Formatter;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0152]: found duplicate lang item `panic_fmt`
[INFO] [stdout]   --> src/lib.rs:54:23
[INFO] [stdout]    |
[INFO] [stdout] 54 | #[lang = "panic_fmt"] fn panic_fmt() -> ! { loop {} }
[INFO] [stdout]    |                       ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: the lang item is first defined in crate `core` (which `kern` depends on)
[INFO] [stdout]    = note: first definition in `core` loaded from /opt/rustwide/rustup-home/toolchains/a77da2d454e6caa227a85b16410b95f93495e7e0/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-0e3656b1fda5fd7b.rlib
[INFO] [stdout]    = note: second definition in the local crate (`kern`)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `#[panic_handler]` function required, but not found
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `core::fmt::Write`
[INFO] [stdout]  --> src/lib.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use core::fmt::Write;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors; 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0152, E0557.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0152`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `kern` due to 5 previous errors; 3 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "0a38610fcaec03baad00a36f222013546b25c8de0ced91a4d919df9021db8cc4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0a38610fcaec03baad00a36f222013546b25c8de0ced91a4d919df9021db8cc4", kill_on_drop: false }`
[INFO] [stdout] 0a38610fcaec03baad00a36f222013546b25c8de0ced91a4d919df9021db8cc4