[INFO] updating cached repository https://github.com/adragott/Serial_Rust_Learning
[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] 793ed8bd526ac92504690f517e2e45b85f92cbc9
[INFO] testing adragott/Serial_Rust_Learning against beta-2020-06-03 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fadragott%2FSerial_Rust_Learning" "/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/adragott/Serial_Rust_Learning on toolchain beta-2020-06-03
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/adragott/Serial_Rust_Learning
[INFO] finished tweaking git repo https://github.com/adragott/Serial_Rust_Learning
[INFO] tweaked toml for git repo https://github.com/adragott/Serial_Rust_Learning written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate git repo https://github.com/adragott/Serial_Rust_Learning already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "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-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=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" "+beta-2020-06-03" "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] 2f8d4d2b8f231434bac70c342779b977cd46fcf2e9e60cb7086a233cb22600aa
[INFO] running `"docker" "start" "-a" "2f8d4d2b8f231434bac70c342779b977cd46fcf2e9e60cb7086a233cb22600aa"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr] error[E0463]: can't find crate for `core`
[INFO] [stderr]   |
[INFO] [stderr]   = note: the `aarch64-unknown-linux-gnu` target may not be installed
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0463`.
[INFO] [stderr] error: could not compile `libc`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "2f8d4d2b8f231434bac70c342779b977cd46fcf2e9e60cb7086a233cb22600aa"`
[INFO] running `"docker" "rm" "-f" "2f8d4d2b8f231434bac70c342779b977cd46fcf2e9e60cb7086a233cb22600aa"`
[INFO] [stdout] 2f8d4d2b8f231434bac70c342779b977cd46fcf2e9e60cb7086a233cb22600aa