[INFO] fetching crate high_mem_utils 0.2.7...
[INFO] checking high_mem_utils-0.2.7 against beta for pr-78714
[INFO] extracting crate high_mem_utils 0.2.7 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate high_mem_utils 0.2.7 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate high_mem_utils 0.2.7
[INFO] finished tweaking crates.io crate high_mem_utils 0.2.7
[INFO] tweaked toml for crates.io crate high_mem_utils 0.2.7 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] d25a0e4b517cbd38c0cc0697a1d39e65a02e1405e7f5e009c995c8026875fd3a
[INFO] running `Command { std: "docker" "start" "-a" "d25a0e4b517cbd38c0cc0697a1d39e65a02e1405e7f5e009c995c8026875fd3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d25a0e4b517cbd38c0cc0697a1d39e65a02e1405e7f5e009c995c8026875fd3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d25a0e4b517cbd38c0cc0697a1d39e65a02e1405e7f5e009c995c8026875fd3a", kill_on_drop: false }`
[INFO] [stdout] d25a0e4b517cbd38c0cc0697a1d39e65a02e1405e7f5e009c995c8026875fd3a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 75c42495026f9b41ffd773324cd624b048750f9c3e6407ce6b22ed2340e082dd
[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" "75c42495026f9b41ffd773324cd624b048750f9c3e6407ce6b22ed2340e082dd", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling fixed_len_str v0.2.9
[INFO] [stderr]    Compiling syn_str v0.1.58
[INFO] [stderr]    Compiling fast_new_type v0.1.7
[INFO] [stderr]     Checking high_mem_utils v0.2.7 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(vec_leak, untagged_unions, const_fn, const_fn_union)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(vec_leak, untagged_unions, const_fn, const_fn_union)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `high_mem_utils`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "75c42495026f9b41ffd773324cd624b048750f9c3e6407ce6b22ed2340e082dd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "75c42495026f9b41ffd773324cd624b048750f9c3e6407ce6b22ed2340e082dd", kill_on_drop: false }`
[INFO] [stdout] 75c42495026f9b41ffd773324cd624b048750f9c3e6407ce6b22ed2340e082dd