[INFO] updating cached repository https://github.com/PEshwar/toy_blockchain
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] c3f9d29fea64ac54da7ebb46da5a04e995585d22
[INFO] checking PEshwar/toy_blockchain against master#bd0bacc694d7d8175804bb6f690cb846bfa4a9ee for pr-71665
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPEshwar%2Ftoy_blockchain" "/workspace/builds/worker-6/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/PEshwar/toy_blockchain on toolchain bd0bacc694d7d8175804bb6f690cb846bfa4a9ee
[INFO] running `"/workspace/cargo-home/bin/cargo" "+bd0bacc694d7d8175804bb6f690cb846bfa4a9ee" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/PEshwar/toy_blockchain
[INFO] finished tweaking git repo https://github.com/PEshwar/toy_blockchain
[INFO] tweaked toml for git repo https://github.com/PEshwar/toy_blockchain written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/PEshwar/toy_blockchain already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+bd0bacc694d7d8175804bb6f690cb846bfa4a9ee" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+bd0bacc694d7d8175804bb6f690cb846bfa4a9ee" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 3fdf23ac03beb1dedaa14950c4390e5bb44df05d0a8ca654c3d7d9babde553ec
[INFO] running `"docker" "start" "-a" "3fdf23ac03beb1dedaa14950c4390e5bb44df05d0a8ca654c3d7d9babde553ec"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling pkg-config v0.3.14
[INFO] [stderr]    Compiling autocfg v0.1.4
[INFO] [stderr]    Compiling cc v1.0.37
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling libc v0.2.60
[INFO] [stderr]    Compiling bitflags v1.1.0
[INFO] [stderr]     Checking lazy_static v1.3.0
[INFO] [stderr]     Checking cfg-if v0.1.9
[INFO] [stderr]     Checking hex v0.3.2
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling openssl-sys v0.9.47
[INFO] [stderr]    Compiling syn v0.15.39
[INFO] [stderr]    Compiling openssl v0.10.23
[INFO] [stderr]    Compiling serde_derive v1.0.94
[INFO] [stderr]     Checking crypto-hash v0.3.3
[INFO] [stderr]     Checking serde v1.0.94
[INFO] [stderr]     Checking serde_json v1.0.40
[INFO] [stderr]     Checking peblock v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: associated function is never used: `new`
[INFO] [stderr]   --> src/main.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     pub fn new(timestamp: u64, transactions: Vec<Transaction>, previous_block: &Block) -> Block {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `genesis`
[INFO] [stderr]   --> src/main.rs:46:5
[INFO] [stderr]    |
[INFO] [stderr] 46 |     pub fn genesis() -> Block {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `to_json`
[INFO] [stderr]   --> src/main.rs:60:5
[INFO] [stderr]    |
[INFO] [stderr] 60 |     pub fn to_json(&self) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `hash`
[INFO] [stderr]   --> src/main.rs:64:5
[INFO] [stderr]    |
[INFO] [stderr] 64 |     pub fn hash(block: &Block) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `is_valid`
[INFO] [stderr]   --> src/main.rs:68:5
[INFO] [stderr]    |
[INFO] [stderr] 68 |     pub fn is_valid(hash: &str, prefix: &str) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `mine_next_block`
[INFO] [stderr]   --> src/main.rs:71:5
[INFO] [stderr]    |
[INFO] [stderr] 71 |     fn mine_next_block(candidate_block: &mut Block, prefix: &str)  {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Blockchain`
[INFO] [stderr]   --> src/main.rs:80:8
[INFO] [stderr]    |
[INFO] [stderr] 80 | struct Blockchain {
[INFO] [stderr]    |        ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 7 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `new`
[INFO] [stderr]   --> src/main.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     pub fn new(timestamp: u64, transactions: Vec<Transaction>, previous_block: &Block) -> Block {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `genesis`
[INFO] [stderr]   --> src/main.rs:46:5
[INFO] [stderr]    |
[INFO] [stderr] 46 |     pub fn genesis() -> Block {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `to_json`
[INFO] [stderr]   --> src/main.rs:60:5
[INFO] [stderr]    |
[INFO] [stderr] 60 |     pub fn to_json(&self) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `hash`
[INFO] [stderr]   --> src/main.rs:64:5
[INFO] [stderr]    |
[INFO] [stderr] 64 |     pub fn hash(block: &Block) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `is_valid`
[INFO] [stderr]   --> src/main.rs:68:5
[INFO] [stderr]    |
[INFO] [stderr] 68 |     pub fn is_valid(hash: &str, prefix: &str) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `mine_next_block`
[INFO] [stderr]   --> src/main.rs:71:5
[INFO] [stderr]    |
[INFO] [stderr] 71 |     fn mine_next_block(candidate_block: &mut Block, prefix: &str)  {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Blockchain`
[INFO] [stderr]   --> src/main.rs:80:8
[INFO] [stderr]    |
[INFO] [stderr] 80 | struct Blockchain {
[INFO] [stderr]    |        ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 7 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 51.95s
[INFO] running `"docker" "inspect" "3fdf23ac03beb1dedaa14950c4390e5bb44df05d0a8ca654c3d7d9babde553ec"`
[INFO] running `"docker" "rm" "-f" "3fdf23ac03beb1dedaa14950c4390e5bb44df05d0a8ca654c3d7d9babde553ec"`
[INFO] [stdout] 3fdf23ac03beb1dedaa14950c4390e5bb44df05d0a8ca654c3d7d9babde553ec