[INFO] fetching crate prng 0.1.1...
[INFO] checking prng-0.1.1 against master#4fa76a4a7742bb9c1febe33019f5a9e7e4839a65 for pr-83744
[INFO] extracting crate prng 0.1.1 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate prng 0.1.1 on toolchain 4fa76a4a7742bb9c1febe33019f5a9e7e4839a65
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate prng 0.1.1
[INFO] finished tweaking crates.io crate prng 0.1.1
[INFO] tweaked toml for crates.io crate prng 0.1.1 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ca30a53d560c9e4640f5450e127c80c341959fae7c8154de5ef3449631b5d000
[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" "ca30a53d560c9e4640f5450e127c80c341959fae7c8154de5ef3449631b5d000", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ca30a53d560c9e4640f5450e127c80c341959fae7c8154de5ef3449631b5d000", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ca30a53d560c9e4640f5450e127c80c341959fae7c8154de5ef3449631b5d000", kill_on_drop: false }`
[INFO] [stdout] ca30a53d560c9e4640f5450e127c80c341959fae7c8154de5ef3449631b5d000
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 75c9ec66d1578a079cdf84715f58238dc893b2368493e728c16c4f5611d01b7e
[INFO] running `Command { std: "docker" "start" "-a" "75c9ec66d1578a079cdf84715f58238dc893b2368493e728c16c4f5611d01b7e", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.93
[INFO] [stderr]     Checking rng_trait v0.1.1
[INFO] [stderr]     Checking prng v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0432]: unresolved import `alloc::arc`
[INFO] [stdout]  --> src/atomic_prng.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | use alloc::arc::Arc;
[INFO] [stdout]   |            ^^^ could not find `arc` in `alloc`
[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 E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `prng`
[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] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "75c9ec66d1578a079cdf84715f58238dc893b2368493e728c16c4f5611d01b7e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "75c9ec66d1578a079cdf84715f58238dc893b2368493e728c16c4f5611d01b7e", kill_on_drop: false }`
[INFO] [stdout] 75c9ec66d1578a079cdf84715f58238dc893b2368493e728c16c4f5611d01b7e