[INFO] fetching crate prng 0.1.1...
[INFO] testing prng-0.1.1 against beta-2021-09-08 for beta-1.56-1
[INFO] extracting crate prng 0.1.1 into /workspace/builds/worker-71/source
[INFO] validating manifest of crates.io crate prng 0.1.1 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "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-71/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "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 fuchsia-cprng v0.1.1
[INFO] [stderr]   Downloaded rand_core v0.4.2
[INFO] [stderr]   Downloaded rand v0.4.6
[INFO] [stderr]   Downloaded libc v0.2.101
[INFO] [stderr]   Downloaded rdrand v0.4.0
[INFO] [stderr]   Downloaded rand v0.3.23
[INFO] [stderr]   Downloaded rand_core v0.3.1
[INFO] [stderr]   Downloaded rng_trait v0.1.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-71/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-71/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" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bf0ff952a51c170889f8fc726ef08904bbff06c5cbc5875fdd6924e574991dc2
[INFO] running `Command { std: "docker" "start" "-a" "bf0ff952a51c170889f8fc726ef08904bbff06c5cbc5875fdd6924e574991dc2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bf0ff952a51c170889f8fc726ef08904bbff06c5cbc5875fdd6924e574991dc2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bf0ff952a51c170889f8fc726ef08904bbff06c5cbc5875fdd6924e574991dc2", kill_on_drop: false }`
[INFO] [stdout] bf0ff952a51c170889f8fc726ef08904bbff06c5cbc5875fdd6924e574991dc2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-71/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-71/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" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 20f40b211139cfce69c0b906cf62fac4f1f3f3e1e8cf9bb6729ff7623eb8843f
[INFO] running `Command { std: "docker" "start" "-a" "20f40b211139cfce69c0b906cf62fac4f1f3f3e1e8cf9bb6729ff7623eb8843f", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rng_trait v0.1.1
[INFO] [stderr]    Compiling 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[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(alloc)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0432, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `prng` due to 3 previous errors
[INFO] running `Command { std: "docker" "inspect" "20f40b211139cfce69c0b906cf62fac4f1f3f3e1e8cf9bb6729ff7623eb8843f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "20f40b211139cfce69c0b906cf62fac4f1f3f3e1e8cf9bb6729ff7623eb8843f", kill_on_drop: false }`
[INFO] [stdout] 20f40b211139cfce69c0b906cf62fac4f1f3f3e1e8cf9bb6729ff7623eb8843f