[INFO] updating cached repository https://github.com/LiamOW/RustyCalculator
[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] 96e97b2ce164d98f042cbee4b5ab1c2fa9f796f0
[INFO] checking LiamOW/RustyCalculator against master#914adf04af1c1a984707f778da3d04590c03d144 for pr-72331
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLiamOW%2FRustyCalculator" "/workspace/builds/worker-14/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-14/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/LiamOW/RustyCalculator on toolchain 914adf04af1c1a984707f778da3d04590c03d144
[INFO] running `"/workspace/cargo-home/bin/cargo" "+914adf04af1c1a984707f778da3d04590c03d144" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/LiamOW/RustyCalculator
[INFO] removed path dependency calculator from git repo https://github.com/LiamOW/RustyCalculator
[INFO] finished tweaking git repo https://github.com/LiamOW/RustyCalculator
[INFO] tweaked toml for git repo https://github.com/LiamOW/RustyCalculator written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate git repo https://github.com/LiamOW/RustyCalculator already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+914adf04af1c1a984707f778da3d04590c03d144" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr] warning: dependency (calculator) specified without providing a local path, Git repository, or version to use. This will be considered an error in future versions
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr] error: the lock file /workspace/builds/worker-14/source/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] [stderr] If you want to try to generate the lock file without accessing the network, use the --offline flag.
[INFO] the lockfile is outdated, regenerating it
[INFO] running `"/workspace/cargo-home/bin/cargo" "+914adf04af1c1a984707f778da3d04590c03d144" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/workspace/cargo-home/bin/cargo" "+914adf04af1c1a984707f778da3d04590c03d144" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr] warning: dependency (calculator) specified without providing a local path, Git repository, or version to use. This will be considered an error in future versions
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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=forbid" "-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" "+914adf04af1c1a984707f778da3d04590c03d144" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 478771c59c4b0a32248a489bb67bcedde34f31f7b7838264188a3b6789ebc480
[INFO] running `"docker" "start" "-a" "478771c59c4b0a32248a489bb67bcedde34f31f7b7838264188a3b6789ebc480"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr] warning: dependency (calculator) specified without providing a local path, Git repository, or version to use. This will be considered an error in future versions
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]     Checking same-file v1.0.6
[INFO] [stderr]     Checking itoa v0.4.5
[INFO] [stderr]    Compiling nix v0.14.1
[INFO] [stderr]     Checking void v1.0.2
[INFO] [stderr]     Checking vec_map v0.0.1
[INFO] [stderr]     Checking unicode-segmentation v1.6.0
[INFO] [stderr]    Compiling ring v0.13.5
[INFO] [stderr]    Compiling unicase v1.4.2
[INFO] [stderr]    Compiling pear_codegen v0.1.2
[INFO] [stderr]    Compiling num-traits v0.2.11
[INFO] [stderr]    Compiling error-chain v0.12.2
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]     Checking time v0.1.43
[INFO] [stderr]     Checking net2 v0.2.34
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking backtrace v0.3.48
[INFO] [stderr]     Checking inotify-sys v0.1.3
[INFO] [stderr]     Checking filetime v0.2.10
[INFO] [stderr]     Checking dirs-sys v0.3.4
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling indexmap v1.3.2
[INFO] [stderr]    Compiling proc-macro2 v1.0.14
[INFO] [stderr]    Compiling log v0.3.9
[INFO] [stderr]     Checking walkdir v2.3.1
[INFO] [stderr]     Checking calculator v0.0.1
[INFO] [stderr]     Checking inotify v0.7.0
[INFO] [stderr]     Checking serde_json v1.0.53
[INFO] [stderr]     Checking unicase_serde v0.1.0
[INFO] [stderr] error[E0635]: unknown feature `collections`
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/calculator-0.0.1/src/expr.rs:4:12
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![feature(collections)]
[INFO] [stderr]   |            ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0635`.
[INFO] [stderr] error: could not compile `calculator`.
[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" "478771c59c4b0a32248a489bb67bcedde34f31f7b7838264188a3b6789ebc480"`
[INFO] running `"docker" "rm" "-f" "478771c59c4b0a32248a489bb67bcedde34f31f7b7838264188a3b6789ebc480"`
[INFO] [stdout] 478771c59c4b0a32248a489bb67bcedde34f31f7b7838264188a3b6789ebc480