[INFO] cloning repository https://github.com/gregorholzmann/rust-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/gregorholzmann/rust-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgregorholzmann%2Frust-playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgregorholzmann%2Frust-playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6e44145369c9374ccf0e294cbae2934d301387e2
[INFO] checking gregorholzmann/rust-playground against master#5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgregorholzmann%2Frust-playground" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/gregorholzmann/rust-playground 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/gregorholzmann/rust-playground
[INFO] finished tweaking git repo https://github.com/gregorholzmann/rust-playground
[INFO] tweaked toml for git repo https://github.com/gregorholzmann/rust-playground written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/gregorholzmann/rust-playground 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-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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] da373818e399a01d87f5c247f551c7a151a0e02f0318d6f2e423cb2031b39bab
[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" "da373818e399a01d87f5c247f551c7a151a0e02f0318d6f2e423cb2031b39bab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "da373818e399a01d87f5c247f551c7a151a0e02f0318d6f2e423cb2031b39bab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da373818e399a01d87f5c247f551c7a151a0e02f0318d6f2e423cb2031b39bab", kill_on_drop: false }`
[INFO] [stdout] da373818e399a01d87f5c247f551c7a151a0e02f0318d6f2e423cb2031b39bab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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] dff073c3476fd92d4084925e273b060edd87bb14636373269f002b4690f96102
[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" "dff073c3476fd92d4084925e273b060edd87bb14636373269f002b4690f96102", kill_on_drop: false }`
[INFO] [stderr]     Checking libc v0.2.26
[INFO] [stderr]     Checking rand v0.3.15
[INFO] [stderr]     Checking rust-playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:86:9
[INFO] [stdout]    |
[INFO] [stdout] 86 |     for x in 0..number_of_cards {
[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: value assigned to `num_value` is never read
[INFO] [stdout]   --> src/main.rs:25:21
[INFO] [stdout]    |
[INFO] [stdout] 25 |             let mut num_value: u8 = 0;
[INFO] [stdout]    |                     ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:101:51
[INFO] [stdout]     |
[INFO] [stdout] 101 | fn end_game(player_hand: Hand, dealer_hand: Hand, mut deck: &mut Vec<Card>) {
[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: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:86:9
[INFO] [stdout]    |
[INFO] [stdout] 86 |     for x in 0..number_of_cards {
[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: value assigned to `num_value` is never read
[INFO] [stdout]   --> src/main.rs:25:21
[INFO] [stdout]    |
[INFO] [stdout] 25 |             let mut num_value: u8 = 0;
[INFO] [stdout]    |                     ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:101:51
[INFO] [stdout]     |
[INFO] [stdout] 101 | fn end_game(player_hand: Hand, dealer_hand: Hand, mut deck: &mut Vec<Card>) {
[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: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.16s
[INFO] running `Command { std: "docker" "inspect" "dff073c3476fd92d4084925e273b060edd87bb14636373269f002b4690f96102", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dff073c3476fd92d4084925e273b060edd87bb14636373269f002b4690f96102", kill_on_drop: false }`
[INFO] [stdout] dff073c3476fd92d4084925e273b060edd87bb14636373269f002b4690f96102