[INFO] cloning repository https://github.com/jelford/project_euler
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jelford/project_euler" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjelford%2Fproject_euler", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjelford%2Fproject_euler'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b7cdcc12bd242142680e4b73c43fdb1605404b77
[INFO] checking jelford/project_euler against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjelford%2Fproject_euler" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jelford/project_euler on toolchain 45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/jelford/project_euler
[INFO] finished tweaking git repo https://github.com/jelford/project_euler
[INFO] tweaked toml for git repo https://github.com/jelford/project_euler written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/jelford/project_euler already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3337548841c2c0c492caf21d74f4a07a0ce80b3a1b62898cb630d4f6bb6712df
[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" "3337548841c2c0c492caf21d74f4a07a0ce80b3a1b62898cb630d4f6bb6712df", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3337548841c2c0c492caf21d74f4a07a0ce80b3a1b62898cb630d4f6bb6712df", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3337548841c2c0c492caf21d74f4a07a0ce80b3a1b62898cb630d4f6bb6712df", kill_on_drop: false }`
[INFO] [stdout] 3337548841c2c0c492caf21d74f4a07a0ce80b3a1b62898cb630d4f6bb6712df
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "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] 88722e1721579d4312efc63798e2151b26d21daa8b0466fc8bf9f10574bf3eba
[INFO] running `Command { std: "docker" "start" "-a" "88722e1721579d4312efc63798e2151b26d21daa8b0466fc8bf9f10574bf3eba", kill_on_drop: false }`
[INFO] [stderr]     Checking project_euler v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/palindromes.rs:66:13
[INFO] [stdout]    |
[INFO] [stdout] 66 |             mem::replace(&mut self.current_digits, updated);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/palindromes.rs:66:13
[INFO] [stdout]    |
[INFO] [stdout] 66 |             mem::replace(&mut self.current_digits, updated);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.44s
[INFO] running `Command { std: "docker" "inspect" "88722e1721579d4312efc63798e2151b26d21daa8b0466fc8bf9f10574bf3eba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "88722e1721579d4312efc63798e2151b26d21daa8b0466fc8bf9f10574bf3eba", kill_on_drop: false }`
[INFO] [stdout] 88722e1721579d4312efc63798e2151b26d21daa8b0466fc8bf9f10574bf3eba