[INFO] cloning repository https://github.com/echochamber/rust_tinkering
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/echochamber/rust_tinkering" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fechochamber%2Frust_tinkering", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fechochamber%2Frust_tinkering'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 12a61eda676f034377caa5a6878c2f72db0806af
[INFO] checking echochamber/rust_tinkering against try#c8bdaa84ec1b37f18f30375e196a65b7602f3790 for pr-73345
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fechochamber%2Frust_tinkering" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/echochamber/rust_tinkering on toolchain c8bdaa84ec1b37f18f30375e196a65b7602f3790
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+c8bdaa84ec1b37f18f30375e196a65b7602f3790" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/echochamber/rust_tinkering
[INFO] finished tweaking git repo https://github.com/echochamber/rust_tinkering
[INFO] tweaked toml for git repo https://github.com/echochamber/rust_tinkering written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/echochamber/rust_tinkering already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+c8bdaa84ec1b37f18f30375e196a65b7602f3790" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr] error: the lock file /workspace/builds/worker-2/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[INFO] the lockfile is outdated, regenerating it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" "+c8bdaa84ec1b37f18f30375e196a65b7602f3790" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+c8bdaa84ec1b37f18f30375e196a65b7602f3790" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+c8bdaa84ec1b37f18f30375e196a65b7602f3790" "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] c8da6ba8b656df80824b25e5c5660516c4a81451e97336ee47e0c93249dbb01b
[INFO] running `Command { std: "docker" "start" "-a" "c8da6ba8b656df80824b25e5c5660516c4a81451e97336ee47e0c93249dbb01b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c8da6ba8b656df80824b25e5c5660516c4a81451e97336ee47e0c93249dbb01b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c8da6ba8b656df80824b25e5c5660516c4a81451e97336ee47e0c93249dbb01b", kill_on_drop: false }`
[INFO] [stdout] c8da6ba8b656df80824b25e5c5660516c4a81451e97336ee47e0c93249dbb01b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+c8bdaa84ec1b37f18f30375e196a65b7602f3790" "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] baf45c45f754706593928c4dfe442cfb20dcd38abb95fabc2e0b472512effd87
[INFO] running `Command { std: "docker" "start" "-a" "baf45c45f754706593928c4dfe442cfb20dcd38abb95fabc2e0b472512effd87", kill_on_drop: false }`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]    Compiling num-bigint v0.3.0
[INFO] [stderr]    Compiling num-rational v0.3.0
[INFO] [stderr]    Compiling num-iter v0.1.41
[INFO] [stderr]     Checking num-complex v0.3.0
[INFO] [stderr]     Checking num v0.3.0
[INFO] [stderr]     Checking rust_euler v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `chars`
[INFO] [stdout]  --> src/reverse_string.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let chars = string_to_reverse.chars();
[INFO] [stdout]   |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_chars`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `chars`
[INFO] [stdout]  --> src/reverse_string.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let chars = string_to_reverse.chars();
[INFO] [stdout]   |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_chars`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` 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 9.58s
[INFO] running `Command { std: "docker" "inspect" "baf45c45f754706593928c4dfe442cfb20dcd38abb95fabc2e0b472512effd87", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "baf45c45f754706593928c4dfe442cfb20dcd38abb95fabc2e0b472512effd87", kill_on_drop: false }`
[INFO] [stdout] baf45c45f754706593928c4dfe442cfb20dcd38abb95fabc2e0b472512effd87