[INFO] cloning repository https://github.com/olegkich/simple-rust-blockchain
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/olegkich/simple-rust-blockchain" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Folegkich%2Fsimple-rust-blockchain", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Folegkich%2Fsimple-rust-blockchain'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a5b8f6388d9543ab7636ee341987318dd4bf3940
[INFO] checking olegkich/simple-rust-blockchain against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Folegkich%2Fsimple-rust-blockchain" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/olegkich/simple-rust-blockchain
[INFO] finished tweaking git repo https://github.com/olegkich/simple-rust-blockchain
[INFO] tweaked toml for git repo https://github.com/olegkich/simple-rust-blockchain written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/olegkich/simple-rust-blockchain on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/olegkich/simple-rust-blockchain already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5d285b8b8890d8a75d64294a91de9346039d30a88538a951c5597a697a59e188
[INFO] running `Command { std: "docker" "start" "-a" "5d285b8b8890d8a75d64294a91de9346039d30a88538a951c5597a697a59e188", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5d285b8b8890d8a75d64294a91de9346039d30a88538a951c5597a697a59e188", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5d285b8b8890d8a75d64294a91de9346039d30a88538a951c5597a697a59e188", kill_on_drop: false }`
[INFO] [stdout] 5d285b8b8890d8a75d64294a91de9346039d30a88538a951c5597a697a59e188
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/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 -Dunmustuse_in_always_ok" "-e" "RUSTDOCFLAGS=--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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 569a7460fb398792f5e7fb14d3298d6c9c5a7e93598e6dabfb8eeb8ed25f5c64
[INFO] running `Command { std: "docker" "start" "-a" "569a7460fb398792f5e7fb14d3298d6c9c5a7e93598e6dabfb8eeb8ed25f5c64", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.138
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]    Compiling libm v0.2.6
[INFO] [stderr]     Checking iana-time-zone v0.1.53
[INFO] [stderr]     Checking digest v0.10.6
[INFO] [stderr]     Checking sha2 v0.10.6
[INFO] [stderr]     Checking time v0.1.45
[INFO] [stderr]     Checking tiny-gradient v0.1.0
[INFO] [stderr]     Checking chrono v0.4.23
[INFO] [stderr]     Checking blockchain v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `ops::Index`
[INFO] [stdout]  --> src/main.rs:5:15
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::{io, ops::Index};
[INFO] [stdout]   |               ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ops::Index`
[INFO] [stdout]  --> src/main.rs:5:15
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::{io, ops::Index};
[INFO] [stdout]   |               ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `previous_hash`, `data`, and `nonce` are never read
[INFO] [stdout]   --> src/blockchain.rs:9:3
[INFO] [stdout]    |
[INFO] [stdout]  6 | pub struct Block {
[INFO] [stdout]    |            ----- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout]  9 |   previous_hash: String,
[INFO] [stdout]    |   ^^^^^^^^^^^^^
[INFO] [stdout] 10 |   data: String,
[INFO] [stdout]    |   ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 13 |   nonce: usize
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Block` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `difficulty` is never read
[INFO] [stdout]   --> src/blockchain.rs:23:3
[INFO] [stdout]    |
[INFO] [stdout] 21 | pub struct Chain {
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 22 |   blocks: Vec<Block>,
[INFO] [stdout] 23 |   difficulty: usize
[INFO] [stdout]    |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/blockchain.rs:44:22
[INFO] [stdout]    |
[INFO] [stdout] 44 |       previous_hash: String::from_str("").unwrap(),
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `blockchain` (bin "blockchain") due to 1 previous error; 3 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: fields `previous_hash`, `data`, and `nonce` are never read
[INFO] [stdout]   --> src/blockchain.rs:9:3
[INFO] [stdout]    |
[INFO] [stdout]  6 | pub struct Block {
[INFO] [stdout]    |            ----- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout]  9 |   previous_hash: String,
[INFO] [stdout]    |   ^^^^^^^^^^^^^
[INFO] [stdout] 10 |   data: String,
[INFO] [stdout]    |   ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 13 |   nonce: usize
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Block` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `difficulty` is never read
[INFO] [stdout]   --> src/blockchain.rs:23:3
[INFO] [stdout]    |
[INFO] [stdout] 21 | pub struct Chain {
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 22 |   blocks: Vec<Block>,
[INFO] [stdout] 23 |   difficulty: usize
[INFO] [stdout]    |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/blockchain.rs:44:22
[INFO] [stdout]    |
[INFO] [stdout] 44 |       previous_hash: String::from_str("").unwrap(),
[INFO] [stdout]    |                      ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `blockchain` (bin "blockchain" test) due to 1 previous error; 3 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "569a7460fb398792f5e7fb14d3298d6c9c5a7e93598e6dabfb8eeb8ed25f5c64", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "569a7460fb398792f5e7fb14d3298d6c9c5a7e93598e6dabfb8eeb8ed25f5c64", kill_on_drop: false }`
[INFO] [stdout] 569a7460fb398792f5e7fb14d3298d6c9c5a7e93598e6dabfb8eeb8ed25f5c64