[INFO] fetching crate fifo 0.2.0...
[INFO] testing fifo-0.2.0 against 1.55.0 for beta-1.56-1
[INFO] extracting crate fifo 0.2.0 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate fifo 0.2.0 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 fifo 0.2.0
[INFO] finished tweaking crates.io crate fifo 0.2.0
[INFO] tweaked toml for crates.io crate fifo 0.2.0 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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] 2dd089710afdad0c545c643fc0866366694ec22640a0ebb581c8cbdcd122f162
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "2dd089710afdad0c545c643fc0866366694ec22640a0ebb581c8cbdcd122f162", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2dd089710afdad0c545c643fc0866366694ec22640a0ebb581c8cbdcd122f162", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2dd089710afdad0c545c643fc0866366694ec22640a0ebb581c8cbdcd122f162", kill_on_drop: false }`
[INFO] [stdout] 2dd089710afdad0c545c643fc0866366694ec22640a0ebb581c8cbdcd122f162
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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] c5c2f6d22bbe4b42a4cf2b3df19b204360595d273fc241cec1879c6431d55752
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "c5c2f6d22bbe4b42a4cf2b3df19b204360595d273fc241cec1879c6431d55752", kill_on_drop: false }`
[INFO] [stderr]    Compiling fifo v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]   --> src/lib.rs:22:12
[INFO] [stdout]    |
[INFO] [stdout] 22 | #![feature(optin_builtin_traits)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^ feature has been removed
[INFO] [stdout]    |
[INFO] [stdout]    = note: renamed to `auto_traits`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `alloc::heap`
[INFO] [stdout]   --> src/lib.rs:30:5
[INFO] [stdout]    |
[INFO] [stdout] 30 | use alloc::heap;
[INFO] [stdout]    |     ^^^^^^^^^^^ no `heap` in the root
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:21:1
[INFO] [stdout]    |
[INFO] [stdout] 21 | #![feature(alloc, heap_api)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:22:1
[INFO] [stdout]    |
[INFO] [stdout] 22 | #![feature(optin_builtin_traits)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/lib.rs:118:6
[INFO] [stdout]     |
[INFO] [stdout] 118 | impl !Sync for Sender {}
[INFO] [stdout]     |      ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/lib.rs:119:6
[INFO] [stdout]     |
[INFO] [stdout] 119 | impl !Sync for Receiver {}
[INFO] [stdout]     |      ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0432, E0554, E0557, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `fifo` due to 7 previous errors
[INFO] running `Command { std: "docker" "inspect" "c5c2f6d22bbe4b42a4cf2b3df19b204360595d273fc241cec1879c6431d55752", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c5c2f6d22bbe4b42a4cf2b3df19b204360595d273fc241cec1879c6431d55752", kill_on_drop: false }`
[INFO] [stdout] c5c2f6d22bbe4b42a4cf2b3df19b204360595d273fc241cec1879c6431d55752