[INFO] cloning repository https://github.com/KoStard/simple_blockchain_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/KoStard/simple_blockchain_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKoStard%2Fsimple_blockchain_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKoStard%2Fsimple_blockchain_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 9b1fde6b298e48d6a62293a9b7feb13f3e53c34e
[INFO] checking KoStard/simple_blockchain_rust against try#f47dd4da3ae8c32c9e65d307bfe640b143e674df for pr-77526
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKoStard%2Fsimple_blockchain_rust" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/KoStard/simple_blockchain_rust on toolchain f47dd4da3ae8c32c9e65d307bfe640b143e674df
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/KoStard/simple_blockchain_rust
[INFO] finished tweaking git repo https://github.com/KoStard/simple_blockchain_rust
[INFO] tweaked toml for git repo https://github.com/KoStard/simple_blockchain_rust written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/KoStard/simple_blockchain_rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded blake2 v0.8.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a88759720d6c3e4adfa5ff5469484af46a1457fe628969169a5a2610db19c71d
[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" "a88759720d6c3e4adfa5ff5469484af46a1457fe628969169a5a2610db19c71d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a88759720d6c3e4adfa5ff5469484af46a1457fe628969169a5a2610db19c71d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a88759720d6c3e4adfa5ff5469484af46a1457fe628969169a5a2610db19c71d", kill_on_drop: false }`
[INFO] [stdout] a88759720d6c3e4adfa5ff5469484af46a1457fe628969169a5a2610db19c71d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ba399e4fc15f3d984c1d51ebdf4ef170f2c8a5f3b3c7afbde418b9f30a43878e
[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" "ba399e4fc15f3d984c1d51ebdf4ef170f2c8a5f3b3c7afbde418b9f30a43878e", kill_on_drop: false }`
[INFO] [stderr]     Checking opaque-debug v0.2.3
[INFO] [stderr]     Checking byte-tools v0.3.1
[INFO] [stderr]     Checking json v0.11.15
[INFO] [stderr]     Checking generic-array v0.12.3
[INFO] [stderr]     Checking digest v0.8.1
[INFO] [stderr]     Checking crypto-mac v0.7.0
[INFO] [stderr]     Checking blake2 v0.8.0
[INFO] [stderr]     Checking simple_blockchain_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:59:9
[INFO] [stdout]    |
[INFO] [stdout] 59 |     let mut stdin = io::stdin();
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:70:9
[INFO] [stdout]    |
[INFO] [stdout] 70 |     let mut data = object! {
[INFO] [stdout]    |         ----^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:63:5
[INFO] [stdout]    |
[INFO] [stdout] 63 |     stdout.flush();
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:59:9
[INFO] [stdout]    |
[INFO] [stdout] 59 |     let mut stdin = io::stdin();
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:70:9
[INFO] [stdout]    |
[INFO] [stdout] 70 |     let mut data = object! {
[INFO] [stdout]    |         ----^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:63:5
[INFO] [stdout]    |
[INFO] [stdout] 63 |     stdout.flush();
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.27s
[INFO] running `Command { std: "docker" "inspect" "ba399e4fc15f3d984c1d51ebdf4ef170f2c8a5f3b3c7afbde418b9f30a43878e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ba399e4fc15f3d984c1d51ebdf4ef170f2c8a5f3b3c7afbde418b9f30a43878e", kill_on_drop: false }`
[INFO] [stdout] ba399e4fc15f3d984c1d51ebdf4ef170f2c8a5f3b3c7afbde418b9f30a43878e