[INFO] cloning repository https://github.com/tamuhey/lockfree_stack_example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/tamuhey/lockfree_stack_example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftamuhey%2Flockfree_stack_example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftamuhey%2Flockfree_stack_example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8d294b684bca139c4572421dcec33595e81dd332
[INFO] testing tamuhey/lockfree_stack_example against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftamuhey%2Flockfree_stack_example" "/workspace/builds/worker-24/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-24/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/tamuhey/lockfree_stack_example 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 git repo https://github.com/tamuhey/lockfree_stack_example
[INFO] finished tweaking git repo https://github.com/tamuhey/lockfree_stack_example
[INFO] tweaked toml for git repo https://github.com/tamuhey/lockfree_stack_example written to /workspace/builds/worker-24/source/Cargo.toml
[INFO] crate git repo https://github.com/tamuhey/lockfree_stack_example 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-24/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-24/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] 3f0444cc913a24599e995a4573bcedc702b0c77390f2a5941144fea4ee8afb86
[INFO] running `Command { std: "docker" "start" "-a" "3f0444cc913a24599e995a4573bcedc702b0c77390f2a5941144fea4ee8afb86", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3f0444cc913a24599e995a4573bcedc702b0c77390f2a5941144fea4ee8afb86", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3f0444cc913a24599e995a4573bcedc702b0c77390f2a5941144fea4ee8afb86", kill_on_drop: false }`
[INFO] [stdout] 3f0444cc913a24599e995a4573bcedc702b0c77390f2a5941144fea4ee8afb86
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-24/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-24/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] 46b3f8ce202317254b96a279a2e75ee0f676f5139cb46906c0f8602458f06d36
[INFO] running `Command { std: "docker" "start" "-a" "46b3f8ce202317254b96a279a2e75ee0f676f5139cb46906c0f8602458f06d36", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.76
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling rayon-core v1.8.0
[INFO] [stderr]    Compiling ppv-lite86 v0.2.9
[INFO] [stderr]    Compiling either v1.6.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling rayon v1.4.0
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling crossbeam-channel v0.4.3
[INFO] [stderr]    Compiling crossbeam-queue v0.2.3
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling crossbeam-deque v0.7.3
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling crossbeam v0.7.3
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling foo v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::mem`
[INFO] [stdout]  --> src/lock.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::mem;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Arc`
[INFO] [stdout]  --> src/lock.rs:3:17
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::sync::{Arc, Mutex};
[INFO] [stdout]   |                 ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::sync::atomic::AtomicPtr::<T>::compare_and_swap`: Use `compare_exchange` or `compare_exchange_weak` instead
[INFO] [stdout]   --> src/leak.rs:32:30
[INFO] [stdout]    |
[INFO] [stdout] 32 |                 if self.head.compare_and_swap(head, next, Release) == head {
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::sync::atomic::AtomicPtr::<T>::compare_and_swap`: Use `compare_exchange` or `compare_exchange_weak` instead
[INFO] [stdout]   --> src/leak.rs:49:26
[INFO] [stdout]    |
[INFO] [stdout] 49 |             if self.head.compare_and_swap(head, n, Release) == head {
[INFO] [stdout]    |                          ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 4 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 `foo` due to 2 previous errors; 4 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "46b3f8ce202317254b96a279a2e75ee0f676f5139cb46906c0f8602458f06d36", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "46b3f8ce202317254b96a279a2e75ee0f676f5139cb46906c0f8602458f06d36", kill_on_drop: false }`
[INFO] [stdout] 46b3f8ce202317254b96a279a2e75ee0f676f5139cb46906c0f8602458f06d36