[INFO] updating cached repository https://github.com/Dhole/rust_learning
[INFO] running `Command { std: "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", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d05e463827e5ebb860a379c3714631acf7e3d728
[INFO] checking Dhole/rust_learning against master#4fb54ed484e2239a3e9eff3be17df00d2a162be3 for pr-73345
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FDhole%2Frust_learning" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Dhole/rust_learning on toolchain 4fb54ed484e2239a3e9eff3be17df00d2a162be3
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fb54ed484e2239a3e9eff3be17df00d2a162be3" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Dhole/rust_learning
[INFO] finished tweaking git repo https://github.com/Dhole/rust_learning
[INFO] tweaked toml for git repo https://github.com/Dhole/rust_learning written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/Dhole/rust_learning already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fb54ed484e2239a3e9eff3be17df00d2a162be3" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:6c9ffe128752d56c8d75334ed354142a5229917ed99767f56566dd8e857ad726" "/opt/rustwide/cargo-home/bin/cargo" "+4fb54ed484e2239a3e9eff3be17df00d2a162be3" "metadata" "--no-deps" "--format-version=1", 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] 79797ebb19f6366fc7ac46e207b31f0554fc02950c3c870bd76d3a05e1226e88
[INFO] running `Command { std: "docker" "start" "-a" "79797ebb19f6366fc7ac46e207b31f0554fc02950c3c870bd76d3a05e1226e88", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "79797ebb19f6366fc7ac46e207b31f0554fc02950c3c870bd76d3a05e1226e88", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "79797ebb19f6366fc7ac46e207b31f0554fc02950c3c870bd76d3a05e1226e88", kill_on_drop: false }`
[INFO] [stdout] 79797ebb19f6366fc7ac46e207b31f0554fc02950c3c870bd76d3a05e1226e88
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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@sha256:6c9ffe128752d56c8d75334ed354142a5229917ed99767f56566dd8e857ad726" "/opt/rustwide/cargo-home/bin/cargo" "+4fb54ed484e2239a3e9eff3be17df00d2a162be3" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 32542963e142d9a222a1f0e3a5ad00db82b3ac2816808466c10a2dcdecf8b39c
[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" "32542963e142d9a222a1f0e3a5ad00db82b3ac2816808466c10a2dcdecf8b39c", kill_on_drop: false }`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]     Checking learn v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0432]: unresolved import `std::rand`
[INFO] [stdout]   --> src/main.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 | use std::rand;
[INFO] [stdout]    |     ^^^^^^^^^ no `rand` in the root
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `std::rand`
[INFO] [stdout]   --> src/main.rs:54:10
[INFO] [stdout]    |
[INFO] [stdout] 54 | use std::rand::Rng;
[INFO] [stdout]    |          ^^^^ could not find `rand` in `std`
[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 E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `learn`.
[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] [stdout] error[E0432]: unresolved import `std::rand`
[INFO] [stdout]   --> src/main.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 | use std::rand;
[INFO] [stdout]    |     ^^^^^^^^^ no `rand` in the root
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `std::rand`
[INFO] [stdout]   --> src/main.rs:54:10
[INFO] [stdout]    |
[INFO] [stdout] 54 | use std::rand::Rng;
[INFO] [stdout]    |          ^^^^ could not find `rand` in `std`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "32542963e142d9a222a1f0e3a5ad00db82b3ac2816808466c10a2dcdecf8b39c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "32542963e142d9a222a1f0e3a5ad00db82b3ac2816808466c10a2dcdecf8b39c", kill_on_drop: false }`
[INFO] [stdout] 32542963e142d9a222a1f0e3a5ad00db82b3ac2816808466c10a2dcdecf8b39c