[INFO] cloning repository https://github.com/mwing/rust-learning
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mwing/rust-learning" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmwing%2Frust-learning", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmwing%2Frust-learning'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b6995c82beabea1a564e29601ae0797928b472a9
[INFO] checking mwing/rust-learning against master#7b3a7819371cef92a187e9bac8f7810ccde15216 for pr-74846
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmwing%2Frust-learning" "/workspace/builds/worker-5/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mwing/rust-learning on toolchain 7b3a7819371cef92a187e9bac8f7810ccde15216
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mwing/rust-learning
[INFO] finished tweaking git repo https://github.com/mwing/rust-learning
[INFO] tweaked toml for git repo https://github.com/mwing/rust-learning written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/mwing/rust-learning already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] error: the lock file /workspace/builds/worker-5/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[INFO] the lockfile is outdated, regenerating it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 `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "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" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a55571366c9ff2d1418e6479e8ba61430f306e04c37f2ee192b64a4dfb2d6d26
[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" "a55571366c9ff2d1418e6479e8ba61430f306e04c37f2ee192b64a4dfb2d6d26", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a55571366c9ff2d1418e6479e8ba61430f306e04c37f2ee192b64a4dfb2d6d26", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a55571366c9ff2d1418e6479e8ba61430f306e04c37f2ee192b64a4dfb2d6d26", kill_on_drop: false }`
[INFO] [stdout] a55571366c9ff2d1418e6479e8ba61430f306e04c37f2ee192b64a4dfb2d6d26
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "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" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] bb3ec779a7ea99081741c54722bf29c629c212c2d586c6059a3a86740bdfcb4e
[INFO] running `Command { std: "docker" "start" "-a" "bb3ec779a7ea99081741c54722bf29c629c212c2d586c6059a3a86740bdfcb4e", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.74
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking ppv-lite86 v0.2.8
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking guessing_game v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.55s
[INFO] running `Command { std: "docker" "inspect" "bb3ec779a7ea99081741c54722bf29c629c212c2d586c6059a3a86740bdfcb4e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bb3ec779a7ea99081741c54722bf29c629c212c2d586c6059a3a86740bdfcb4e", kill_on_drop: false }`
[INFO] [stdout] bb3ec779a7ea99081741c54722bf29c629c212c2d586c6059a3a86740bdfcb4e