[INFO] updating cached repository https://github.com/knapply/pygrex
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] a59a03805a26d53ce98088c5edb6533b24512bf7
[INFO] testing knapply/pygrex against 1.44.0 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fknapply%2Fpygrex" "/workspace/builds/worker-1/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/knapply/pygrex on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/knapply/pygrex
[INFO] finished tweaking git repo https://github.com/knapply/pygrex
[INFO] tweaked toml for git repo https://github.com/knapply/pygrex written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/knapply/pygrex already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.44.0" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9bf0a19ee98b210a721bf57d4b0926dfe8210e7d6633cb41f032ab5825882579
[INFO] running `"docker" "start" "-a" "9bf0a19ee98b210a721bf57d4b0926dfe8210e7d6633cb41f032ab5825882579"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling proc-macro2 v1.0.10
[INFO] [stderr]    Compiling syn v1.0.18
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling ryu v1.0.4
[INFO] [stderr]    Compiling serde v1.0.106
[INFO] [stderr]    Compiling proc-macro-hack v0.5.15
[INFO] [stderr]    Compiling regex-syntax v0.6.17
[INFO] [stderr]    Compiling unicode-segmentation v1.6.0
[INFO] [stderr]    Compiling unicode-width v0.1.7
[INFO] [stderr]    Compiling itoa v0.4.5
[INFO] [stderr]    Compiling unic-common v0.9.0
[INFO] [stderr]    Compiling rawpointer v0.2.1
[INFO] [stderr]    Compiling inventory v0.1.6
[INFO] [stderr]    Compiling ndarray v0.13.1
[INFO] [stderr]    Compiling unindent v0.1.5
[INFO] [stderr]    Compiling unic-char-range v0.9.0
[INFO] [stderr]    Compiling fixedbitset v0.2.0
[INFO] [stderr]    Compiling either v1.5.3
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.2
[INFO] [stderr]    Compiling proc-macro-error v1.0.2
[INFO] [stderr]    Compiling lock_api v0.3.4
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lock_api-0.3.4/src/lib.rs:91:34
[INFO] [stderr]    |
[INFO] [stderr] 91 | #![cfg_attr(feature = "nightly", feature(const_fn))]
[INFO] [stderr]    |                                  ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling matrixmultiply v0.2.3
[INFO] [stderr]    Compiling unic-ucd-version v0.9.0
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr]    Compiling unic-char-property v0.9.0
[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 `"docker" "inspect" "9bf0a19ee98b210a721bf57d4b0926dfe8210e7d6633cb41f032ab5825882579"`
[INFO] running `"docker" "rm" "-f" "9bf0a19ee98b210a721bf57d4b0926dfe8210e7d6633cb41f032ab5825882579"`
[INFO] [stdout] 9bf0a19ee98b210a721bf57d4b0926dfe8210e7d6633cb41f032ab5825882579