[INFO] fetching crate basic_allocator 0.1.6...
[INFO] testing basic_allocator-0.1.6 against 1.55.0 for beta-1.56-1
[INFO] extracting crate basic_allocator 0.1.6 into /workspace/builds/worker-108/source
[INFO] validating manifest of crates.io crate basic_allocator 0.1.6 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate basic_allocator 0.1.6
[INFO] finished tweaking crates.io crate basic_allocator 0.1.6
[INFO] tweaked toml for crates.io crate basic_allocator 0.1.6 written to /workspace/builds/worker-108/source/Cargo.toml
[INFO] crate crates.io crate basic_allocator 0.1.6 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded errno v0.2.6
[INFO] [stderr]   Downloaded test-env-log v0.2.2
[INFO] [stderr]   Downloaded sysconf v0.3.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8aacba1760566beef05c5a814f0dd3fa904ce1ad8135e9830977cb7cebce4cf0
[INFO] running `Command { std: "docker" "start" "-a" "8aacba1760566beef05c5a814f0dd3fa904ce1ad8135e9830977cb7cebce4cf0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8aacba1760566beef05c5a814f0dd3fa904ce1ad8135e9830977cb7cebce4cf0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8aacba1760566beef05c5a814f0dd3fa904ce1ad8135e9830977cb7cebce4cf0", kill_on_drop: false }`
[INFO] [stdout] 8aacba1760566beef05c5a814f0dd3fa904ce1ad8135e9830977cb7cebce4cf0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/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=warn" "-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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d1fe279598e7e8bd17d1c5a3bd2dc4eed4101c7431058674440b95c4c769bf7b
[INFO] running `Command { std: "docker" "start" "-a" "d1fe279598e7e8bd17d1c5a3bd2dc4eed4101c7431058674440b95c4c769bf7b", kill_on_drop: false }`
[INFO] [stderr]    Compiling basic_allocator v0.1.6 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:40
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![cfg_attr(not(feature = "use_libc"), feature(asm))]
[INFO] [stdout]   |                                        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated function `core::sync::atomic::spin_loop_hint`: use hint::spin_loop instead
[INFO] [stdout]    --> src/allocators.rs:365:33
[INFO] [stdout]     |
[INFO] [stdout] 365 |             core::sync::atomic::spin_loop_hint();
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `core::sync::atomic::AtomicU8::compare_and_swap`: Use `compare_exchange` or `compare_exchange_weak` instead
[INFO] [stdout]    --> src/allocators.rs:347:35
[INFO] [stdout]     |
[INFO] [stdout] 347 |         let mut state = self.init.compare_and_swap(0, 1, Ordering::SeqCst);
[INFO] [stdout]     |                                   ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `basic_allocator` due to 2 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "d1fe279598e7e8bd17d1c5a3bd2dc4eed4101c7431058674440b95c4c769bf7b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d1fe279598e7e8bd17d1c5a3bd2dc4eed4101c7431058674440b95c4c769bf7b", kill_on_drop: false }`
[INFO] [stdout] d1fe279598e7e8bd17d1c5a3bd2dc4eed4101c7431058674440b95c4c769bf7b