[INFO] fetching crate lb64 0.1.2...
[INFO] testing lb64-0.1.2 against 1.47.0 for beta-1.48-1
[INFO] extracting crate lb64 0.1.2 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate lb64 0.1.2 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate lb64 0.1.2
[INFO] finished tweaking crates.io crate lb64 0.1.2
[INFO] tweaked toml for crates.io crate lb64 0.1.2 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "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] 3d92569613d667da86b39990baab9aed7ec43bfec6686b55d47e9bc286462261
[INFO] running `Command { std: "docker" "start" "-a" "3d92569613d667da86b39990baab9aed7ec43bfec6686b55d47e9bc286462261", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3d92569613d667da86b39990baab9aed7ec43bfec6686b55d47e9bc286462261", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3d92569613d667da86b39990baab9aed7ec43bfec6686b55d47e9bc286462261", kill_on_drop: false }`
[INFO] [stdout] 3d92569613d667da86b39990baab9aed7ec43bfec6686b55d47e9bc286462261
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 675102b3e3e720a86c9e44cee2cd724747292a40ab008fdbca2883db065db628
[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" "675102b3e3e720a86c9e44cee2cd724747292a40ab008fdbca2883db065db628", kill_on_drop: false }`
[INFO] [stderr]    Compiling lb64 v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:40:1
[INFO] [stdout]    |
[INFO] [stdout] 40 | #![feature(no_panic_pow)]
[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 `lb64`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "675102b3e3e720a86c9e44cee2cd724747292a40ab008fdbca2883db065db628", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "675102b3e3e720a86c9e44cee2cd724747292a40ab008fdbca2883db065db628", kill_on_drop: false }`
[INFO] [stdout] 675102b3e3e720a86c9e44cee2cd724747292a40ab008fdbca2883db065db628
