[INFO] fetching crate ramp-primes 0.4.1...
[INFO] testing ramp-primes-0.4.1 against 1.49.0 for beta-1.50-1
[INFO] extracting crate ramp-primes 0.4.1 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate ramp-primes 0.4.1 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 ramp-primes 0.4.1
[INFO] finished tweaking crates.io crate ramp-primes 0.4.1
[INFO] tweaked toml for crates.io crate ramp-primes 0.4.1 written to /workspace/builds/worker-9/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] [stderr]     Blocking waiting for file lock on package cache
[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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3c43a01cf20c3a05b05b0c9c30d25be8343959641f8e17aeae3bae149a968286
[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" "3c43a01cf20c3a05b05b0c9c30d25be8343959641f8e17aeae3bae149a968286", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3c43a01cf20c3a05b05b0c9c30d25be8343959641f8e17aeae3bae149a968286", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3c43a01cf20c3a05b05b0c9c30d25be8343959641f8e17aeae3bae149a968286", kill_on_drop: false }`
[INFO] [stdout] 3c43a01cf20c3a05b05b0c9c30d25be8343959641f8e17aeae3bae149a968286
[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=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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9fa48d89fae51a4ba5c1608d0981104ed7857261d5528a7118094d5d1cb58ec7
[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" "9fa48d89fae51a4ba5c1608d0981104ed7857261d5528a7118094d5d1cb58ec7", kill_on_drop: false }`
[INFO] [stderr]    Compiling rustc-cfg v0.2.0
[INFO] [stderr]    Compiling hamming v0.1.3
[INFO] [stderr]    Compiling ieee754 v0.2.6
[INFO] [stderr]    Compiling num-traits v0.1.43
[INFO] [stderr]    Compiling ramp v0.5.9
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/ramp-0.5.9/src/lib.rs:17:1
[INFO] [stdout]    |
[INFO] [stdout] 17 | #![feature(core_intrinsics, asm, allocator_api)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/ramp-0.5.9/src/lib.rs:18:1
[INFO] [stdout]    |
[INFO] [stdout] 18 | #![feature(step_trait, step_trait_ext, ptr_internals, raw_vec_internals)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `ramp`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "9fa48d89fae51a4ba5c1608d0981104ed7857261d5528a7118094d5d1cb58ec7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9fa48d89fae51a4ba5c1608d0981104ed7857261d5528a7118094d5d1cb58ec7", kill_on_drop: false }`
[INFO] [stdout] 9fa48d89fae51a4ba5c1608d0981104ed7857261d5528a7118094d5d1cb58ec7