[INFO] updating cached repository https://github.com/tynr426/regex_learn
[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] f59ec04f199a67c8bdaebe162b45a52c8b8e4cb5
[INFO] checking tynr426/regex_learn against try#6024cfef3a82f9a7688f07054f1650081bad3af5 for pr-74130
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftynr426%2Fregex_learn" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/tynr426/regex_learn on toolchain 6024cfef3a82f9a7688f07054f1650081bad3af5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/tynr426/regex_learn
[INFO] finished tweaking git repo https://github.com/tynr426/regex_learn
[INFO] tweaked toml for git repo https://github.com/tynr426/regex_learn written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/tynr426/regex_learn already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "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] 1c0e0c2a148306a666055e857443f12772a11af87135118095f9ab92abf600c1
[INFO] running `Command { std: "docker" "start" "-a" "1c0e0c2a148306a666055e857443f12772a11af87135118095f9ab92abf600c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1c0e0c2a148306a666055e857443f12772a11af87135118095f9ab92abf600c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1c0e0c2a148306a666055e857443f12772a11af87135118095f9ab92abf600c1", kill_on_drop: false }`
[INFO] [stdout] 1c0e0c2a148306a666055e857443f12772a11af87135118095f9ab92abf600c1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 87e170cbee2c04c8e0392557c4268a855d845a3eac9b8e9e1e2cd43c494ef2fc
[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" "87e170cbee2c04c8e0392557c4268a855d845a3eac9b8e9e1e2cd43c494ef2fc", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking aho-corasick v0.7.6
[INFO] [stderr]     Checking regex v1.3.1
[INFO] [stderr]     Checking regex_learn v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let mut str2 = "{xy:7,xx:\"kk\",\"key\":\"bbb\"}";
[INFO] [stdout]    |         ----^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let mut str2 = "{xy:7,xx:\"kk\",\"key\":\"bbb\"}";
[INFO] [stdout]    |         ----^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.89s
[INFO] running `Command { std: "docker" "inspect" "87e170cbee2c04c8e0392557c4268a855d845a3eac9b8e9e1e2cd43c494ef2fc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "87e170cbee2c04c8e0392557c4268a855d845a3eac9b8e9e1e2cd43c494ef2fc", kill_on_drop: false }`
[INFO] [stdout] 87e170cbee2c04c8e0392557c4268a855d845a3eac9b8e9e1e2cd43c494ef2fc