[INFO] fetching crate rems 0.0.2...
[INFO] testing rems-0.0.2 against 1.47.0 for beta-1.48-1
[INFO] extracting crate rems 0.0.2 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate rems 0.0.2 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 rems 0.0.2
[INFO] finished tweaking crates.io crate rems 0.0.2
[INFO] tweaked toml for crates.io crate rems 0.0.2 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate crates.io crate rems 0.0.2 already has a lockfile, it will not be regenerated
[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-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] 2f16cd2f14d219d8c746b350cbe4a062e9c46b20f98d1fe56e8d410fba58024b
[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" "2f16cd2f14d219d8c746b350cbe4a062e9c46b20f98d1fe56e8d410fba58024b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2f16cd2f14d219d8c746b350cbe4a062e9c46b20f98d1fe56e8d410fba58024b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2f16cd2f14d219d8c746b350cbe4a062e9c46b20f98d1fe56e8d410fba58024b", kill_on_drop: false }`
[INFO] [stdout] 2f16cd2f14d219d8c746b350cbe4a062e9c46b20f98d1fe56e8d410fba58024b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] 62db6269edac7ce68667456c10331980e3463ec8d183116ff15373ec545ed199
[INFO] running `Command { std: "docker" "start" "-a" "62db6269edac7ce68667456c10331980e3463ec8d183116ff15373ec545ed199", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.9
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling libc v0.2.74
[INFO] [stderr]    Compiling version_check v0.9.1
[INFO] [stderr]    Compiling serde v1.0.105
[INFO] [stderr]    Compiling ryu v1.0.3
[INFO] [stderr]    Compiling smallvec v1.4.0
[INFO] [stderr]    Compiling proc-macro-hack v0.5.14
[INFO] [stderr]    Compiling itoa v0.4.5
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling regex-syntax v0.6.17
[INFO] [stderr]    Compiling unindent v0.1.5
[INFO] [stderr]    Compiling instant v0.1.6
[INFO] [stderr]    Compiling ppv-lite86 v0.2.6
[INFO] [stderr]    Compiling linked-hash-map v0.5.2
[INFO] [stderr]    Compiling unicode-width v0.1.7
[INFO] [stderr]    Compiling rayon-core v1.7.0
[INFO] [stderr]    Compiling pyo3 v0.11.1
[INFO] [stderr]    Compiling vec_map v0.8.1
[INFO] [stderr]    Compiling md5 v0.6.1
[INFO] [stderr]    Compiling hex v0.3.2
[INFO] [stderr]    Compiling remove_dir_all v0.5.2
[INFO] [stderr]    Compiling dtoa v0.4.5
[INFO] [stderr]    Compiling lock_api v0.3.4
[INFO] [stderr]    Compiling lock_api v0.4.1
[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/lock_api-0.3.4/src/lib.rs:91:34
[INFO] [stdout]    |
[INFO] [stdout] 91 | #![cfg_attr(feature = "nightly", feature(const_fn))]
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling yaml-rust v0.4.3
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling indexmap v1.3.2
[INFO] [stderr]    Compiling num-traits v0.2.11
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[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 `lock_api`.
[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" "62db6269edac7ce68667456c10331980e3463ec8d183116ff15373ec545ed199", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "62db6269edac7ce68667456c10331980e3463ec8d183116ff15373ec545ed199", kill_on_drop: false }`
[INFO] [stdout] 62db6269edac7ce68667456c10331980e3463ec8d183116ff15373ec545ed199
