[INFO] fetching crate float_fast_print 0.1.2...
[INFO] testing float_fast_print-0.1.2 against 1.49.0 for beta-1.50-1
[INFO] extracting crate float_fast_print 0.1.2 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate float_fast_print 0.1.2 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate float_fast_print 0.1.2
[INFO] finished tweaking crates.io crate float_fast_print 0.1.2
[INFO] tweaked toml for crates.io crate float_fast_print 0.1.2 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] dcbeaa8c7e7d33e8181bfc2b5c552c789699708df6c9ca58dc4de123e11dea67
[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" "dcbeaa8c7e7d33e8181bfc2b5c552c789699708df6c9ca58dc4de123e11dea67", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dcbeaa8c7e7d33e8181bfc2b5c552c789699708df6c9ca58dc4de123e11dea67", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dcbeaa8c7e7d33e8181bfc2b5c552c789699708df6c9ca58dc4de123e11dea67", kill_on_drop: false }`
[INFO] [stdout] dcbeaa8c7e7d33e8181bfc2b5c552c789699708df6c9ca58dc4de123e11dea67
[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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7f0d54b125032d35e51a2c39efe6d491f57ea0e6c7aeb932abf187d992bd01ed
[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" "7f0d54b125032d35e51a2c39efe6d491f57ea0e6c7aeb932abf187d992bd01ed", kill_on_drop: false }`
[INFO] [stderr]    Compiling float_fast_print v0.1.2 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.84s
[INFO] running `Command { std: "docker" "inspect" "7f0d54b125032d35e51a2c39efe6d491f57ea0e6c7aeb932abf187d992bd01ed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7f0d54b125032d35e51a2c39efe6d491f57ea0e6c7aeb932abf187d992bd01ed", kill_on_drop: false }`
[INFO] [stdout] 7f0d54b125032d35e51a2c39efe6d491f57ea0e6c7aeb932abf187d992bd01ed
[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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9a4205535ab2a36c5160fbad6a88bcccdb4d6cc5b757d2604cd1e81c34858512
[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" "9a4205535ab2a36c5160fbad6a88bcccdb4d6cc5b757d2604cd1e81c34858512", kill_on_drop: false }`
[INFO] [stderr]    Compiling rand v0.5.6
[INFO] [stderr]    Compiling float_fast_print v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> tests/benchmarks.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> tests/exhaustive.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[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 `float_fast_print`
[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" "9a4205535ab2a36c5160fbad6a88bcccdb4d6cc5b757d2604cd1e81c34858512", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9a4205535ab2a36c5160fbad6a88bcccdb4d6cc5b757d2604cd1e81c34858512", kill_on_drop: false }`
[INFO] [stdout] 9a4205535ab2a36c5160fbad6a88bcccdb4d6cc5b757d2604cd1e81c34858512