[INFO] cloning repository https://github.com/RTK99/rust-beginners
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/RTK99/rust-beginners" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRTK99%2Frust-beginners", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRTK99%2Frust-beginners'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1a0528da4b179c687ab1b7d14662767504ca87db
[INFO] checking RTK99/rust-beginners against master#5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRTK99%2Frust-beginners" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/RTK99/rust-beginners on toolchain 5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/RTK99/rust-beginners
[INFO] finished tweaking git repo https://github.com/RTK99/rust-beginners
[INFO] tweaked toml for git repo https://github.com/RTK99/rust-beginners written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/RTK99/rust-beginners already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 18c6b89f7557e15b0c3206e48c257e67273759cc6f2d79ecee477a1c0c5d4959
[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" "18c6b89f7557e15b0c3206e48c257e67273759cc6f2d79ecee477a1c0c5d4959", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "18c6b89f7557e15b0c3206e48c257e67273759cc6f2d79ecee477a1c0c5d4959", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "18c6b89f7557e15b0c3206e48c257e67273759cc6f2d79ecee477a1c0c5d4959", kill_on_drop: false }`
[INFO] [stdout] 18c6b89f7557e15b0c3206e48c257e67273759cc6f2d79ecee477a1c0c5d4959
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fbdfc9c4b098971b83c2f0f10cdb68fead92f5963ae5bdfa079927107daa71bf
[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" "fbdfc9c4b098971b83c2f0f10cdb68fead92f5963ae5bdfa079927107daa71bf", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.47
[INFO] [stderr]     Checking structs v0.1.0 (/opt/rustwide/workdir/structs)
[INFO] [stderr]     Checking control-flow v0.1.0 (/opt/rustwide/workdir/control-flow)
[INFO] [stderr]     Checking variables v0.1.0 (/opt/rustwide/workdir/variables)
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> variables/src/main.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let x: i32 = 1111; // With type annotation/
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> variables/src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let x = 1111; // Type will be inferred.
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> variables/src/main.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let mut x = "I can be mutable!";
[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] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> variables/src/main.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let x: i32 = 1111; // With type annotation/
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> variables/src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let x = 1111; // Type will be inferred.
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> variables/src/main.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let mut x = "I can be mutable!";
[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] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand v0.4.5
[INFO] [stderr]     Checking rand v0.3.22
[INFO] [stderr]     Checking guessing-game v0.1.0 (/opt/rustwide/workdir/guessing-game)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.82s
[INFO] running `Command { std: "docker" "inspect" "fbdfc9c4b098971b83c2f0f10cdb68fead92f5963ae5bdfa079927107daa71bf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fbdfc9c4b098971b83c2f0f10cdb68fead92f5963ae5bdfa079927107daa71bf", kill_on_drop: false }`
[INFO] [stdout] fbdfc9c4b098971b83c2f0f10cdb68fead92f5963ae5bdfa079927107daa71bf