[INFO] fetching crate tt-num 0.1.0...
[INFO] testing tt-num-0.1.0 against 1.47.0 for beta-1.48-1
[INFO] extracting crate tt-num 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate tt-num 0.1.0 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 tt-num 0.1.0
[INFO] finished tweaking crates.io crate tt-num 0.1.0
[INFO] tweaked toml for crates.io crate tt-num 0.1.0 written to /workspace/builds/worker-4/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-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] [stdout] 426753e43c9547d1bf5af768c3b4191eba2aeeb9d02dca1882faf79286cdf2f9
[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" "426753e43c9547d1bf5af768c3b4191eba2aeeb9d02dca1882faf79286cdf2f9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "426753e43c9547d1bf5af768c3b4191eba2aeeb9d02dca1882faf79286cdf2f9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "426753e43c9547d1bf5af768c3b4191eba2aeeb9d02dca1882faf79286cdf2f9", kill_on_drop: false }`
[INFO] [stdout] 426753e43c9547d1bf5af768c3b4191eba2aeeb9d02dca1882faf79286cdf2f9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 975b3b211e11508edcaad94993dde10acf27a3c8e54751b13dff5d17b9a66013
[INFO] running `Command { std: "docker" "start" "-a" "975b3b211e11508edcaad94993dde10acf27a3c8e54751b13dff5d17b9a66013", kill_on_drop: false }`
[INFO] [stderr]    Compiling tt-call v1.0.7
[INFO] [stderr]    Compiling tt-num v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.32s
[INFO] running `Command { std: "docker" "inspect" "975b3b211e11508edcaad94993dde10acf27a3c8e54751b13dff5d17b9a66013", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "975b3b211e11508edcaad94993dde10acf27a3c8e54751b13dff5d17b9a66013", kill_on_drop: false }`
[INFO] [stdout] 975b3b211e11508edcaad94993dde10acf27a3c8e54751b13dff5d17b9a66013
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0ecd3ab5390f14f162a78d7f13f4538dcedef768a239b2c3f0a06656e2e263f7
[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" "0ecd3ab5390f14f162a78d7f13f4538dcedef768a239b2c3f0a06656e2e263f7", kill_on_drop: false }`
[INFO] [stderr]    Compiling tt-num v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> examples/times.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(use_extern_macros)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `tt-num`.
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[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" "0ecd3ab5390f14f162a78d7f13f4538dcedef768a239b2c3f0a06656e2e263f7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0ecd3ab5390f14f162a78d7f13f4538dcedef768a239b2c3f0a06656e2e263f7", kill_on_drop: false }`
[INFO] [stdout] 0ecd3ab5390f14f162a78d7f13f4538dcedef768a239b2c3f0a06656e2e263f7
