[INFO] cloning repository https://github.com/MubasherFiaz/learn_git2
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/MubasherFiaz/learn_git2" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMubasherFiaz%2Flearn_git2", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMubasherFiaz%2Flearn_git2'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 560061b66032f0ac27a829790e583828b5505d95
[INFO] checking MubasherFiaz/learn_git2 against master#4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5 for pr-81174
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMubasherFiaz%2Flearn_git2" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/MubasherFiaz/learn_git2 on toolchain 4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/MubasherFiaz/learn_git2
[INFO] finished tweaking git repo https://github.com/MubasherFiaz/learn_git2
[INFO] tweaked toml for git repo https://github.com/MubasherFiaz/learn_git2 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/MubasherFiaz/learn_git2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "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] cc976301114f2f1ab0e31be11c9d2b82145f021e42fef74174608261ddb6e708
[INFO] running `Command { std: "docker" "start" "-a" "cc976301114f2f1ab0e31be11c9d2b82145f021e42fef74174608261ddb6e708", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cc976301114f2f1ab0e31be11c9d2b82145f021e42fef74174608261ddb6e708", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cc976301114f2f1ab0e31be11c9d2b82145f021e42fef74174608261ddb6e708", kill_on_drop: false }`
[INFO] [stdout] cc976301114f2f1ab0e31be11c9d2b82145f021e42fef74174608261ddb6e708
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9a54a87fe0d5adf2ddf3264ce29becd221253b02d6eb161f4f25befe3e46d2c4
[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" "9a54a87fe0d5adf2ddf3264ce29becd221253b02d6eb161f4f25befe3e46d2c4", kill_on_drop: false }`
[INFO] [stderr]     Checking pre v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]    --> src/main.rs:104:8
[INFO] [stdout]     |
[INFO] [stdout] 104 | return &s[0..i];
[INFO] [stdout]     |        ^^^^^^^^ expected `()`, found `&str`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0308`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `pre`
[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[E0308]: mismatched types
[INFO] [stdout]    --> src/main.rs:104:8
[INFO] [stdout]     |
[INFO] [stdout] 104 | return &s[0..i];
[INFO] [stdout]     |        ^^^^^^^^ expected `()`, found `&str`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0308`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "9a54a87fe0d5adf2ddf3264ce29becd221253b02d6eb161f4f25befe3e46d2c4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9a54a87fe0d5adf2ddf3264ce29becd221253b02d6eb161f4f25befe3e46d2c4", kill_on_drop: false }`
[INFO] [stdout] 9a54a87fe0d5adf2ddf3264ce29becd221253b02d6eb161f4f25befe3e46d2c4