[INFO] cloning repository https://github.com/kajstof/RustCrashCourse
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kajstof/RustCrashCourse" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkajstof%2FRustCrashCourse", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkajstof%2FRustCrashCourse'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 7775f74297feea7b3aa5604e788118eb5717f33f
[INFO] checking kajstof/RustCrashCourse against try#3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkajstof%2FRustCrashCourse" "/workspace/builds/worker-15/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-15/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kajstof/RustCrashCourse on toolchain 3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/kajstof/RustCrashCourse
[INFO] finished tweaking git repo https://github.com/kajstof/RustCrashCourse
[INFO] tweaked toml for git repo https://github.com/kajstof/RustCrashCourse written to /workspace/builds/worker-15/source/Cargo.toml
[INFO] crate git repo https://github.com/kajstof/RustCrashCourse already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5f38724019e7763e472ccbd68acda5206dbcfdd0717ff176a826932d8f852695
[INFO] running `Command { std: "docker" "start" "-a" "5f38724019e7763e472ccbd68acda5206dbcfdd0717ff176a826932d8f852695", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5f38724019e7763e472ccbd68acda5206dbcfdd0717ff176a826932d8f852695", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5f38724019e7763e472ccbd68acda5206dbcfdd0717ff176a826932d8f852695", kill_on_drop: false }`
[INFO] [stdout] 5f38724019e7763e472ccbd68acda5206dbcfdd0717ff176a826932d8f852695
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4bb40006f28fa14d303103898174ce0b36bb8318ed04991387435682a317194b
[INFO] running `Command { std: "docker" "start" "-a" "4bb40006f28fa14d303103898174ce0b36bb8318ed04991387435682a317194b", kill_on_drop: false }`
[INFO] [stderr]     Checking rust_crash_course v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/pointer_ref.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let mut vec2 = &vec1;
[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] error[E0596]: cannot borrow `*vec2` as mutable, as it is behind a `&` reference
[INFO] [stdout]   --> src/pointer_ref.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let mut vec2 = &vec1;
[INFO] [stdout]    |                    ----- help: consider changing this to be a mutable reference: `&mut vec1`
[INFO] [stdout] 15 |     vec2.push(5);
[INFO] [stdout]    |     ^^^^ `vec2` is a `&` reference, so the data it refers to cannot be borrowed as mutable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0596`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust_crash_course` due to 2 previous errors; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/pointer_ref.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let mut vec2 = &vec1;
[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] [stderr] error: build failed
[INFO] [stdout] error[E0596]: cannot borrow `*vec2` as mutable, as it is behind a `&` reference
[INFO] [stdout]   --> src/pointer_ref.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let mut vec2 = &vec1;
[INFO] [stdout]    |                    ----- help: consider changing this to be a mutable reference: `&mut vec1`
[INFO] [stdout] 15 |     vec2.push(5);
[INFO] [stdout]    |     ^^^^ `vec2` is a `&` reference, so the data it refers to cannot be borrowed as mutable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0596`.
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "4bb40006f28fa14d303103898174ce0b36bb8318ed04991387435682a317194b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4bb40006f28fa14d303103898174ce0b36bb8318ed04991387435682a317194b", kill_on_drop: false }`
[INFO] [stdout] 4bb40006f28fa14d303103898174ce0b36bb8318ed04991387435682a317194b