[INFO] updating cached repository christiansakai/toy_blockchain_rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/christiansakai/toy_blockchain_rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/christiansakai/toy_blockchain_rust" "work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/christiansakai/toy_blockchain_rust"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/christiansakai/toy_blockchain_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/christiansakai/toy_blockchain_rust" "work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/christiansakai/toy_blockchain_rust"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/christiansakai/toy_blockchain_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 9949e005ba597eb2d68f7dade5f7404dd445c870
[INFO] sha for GitHub repo christiansakai/toy_blockchain_rust: 9949e005ba597eb2d68f7dade5f7404dd445c870
[INFO] validating manifest of christiansakai/toy_blockchain_rust on toolchain master#60960a260f7b5c695fd0717311d72ce62dd4eb43
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of christiansakai/toy_blockchain_rust on toolchain try#266783e4e09e4e9d5307c1c8e695659c58bbcac7
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing christiansakai/toy_blockchain_rust
[INFO] finished frobbing christiansakai/toy_blockchain_rust
[INFO] frobbed toml for christiansakai/toy_blockchain_rust written to work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/christiansakai/toy_blockchain_rust/Cargo.toml
[INFO] started frobbing christiansakai/toy_blockchain_rust
[INFO] finished frobbing christiansakai/toy_blockchain_rust
[INFO] frobbed toml for christiansakai/toy_blockchain_rust written to work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/christiansakai/toy_blockchain_rust/Cargo.toml
[INFO] crate christiansakai/toy_blockchain_rust already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking christiansakai/toy_blockchain_rust against try#266783e4e09e4e9d5307c1c8e695659c58bbcac7 for pr-63376
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63376/worker-3/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/christiansakai/toy_blockchain_rust:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 1ee4401fcf2e740b2a58ece2f4b933b9c3d9dfd8642fc8b16adf67848e12aa6c
[INFO] running `"docker" "start" "-a" "1ee4401fcf2e740b2a58ece2f4b933b9c3d9dfd8642fc8b16adf67848e12aa6c"`
[INFO] [stderr]    Compiling serde v1.0.75
[INFO] [stderr]    Compiling syn v0.14.9
[INFO] [stderr]     Checking digest v0.7.5
[INFO] [stderr]     Checking sha2 v0.7.1
[INFO] [stderr]    Compiling serde_derive v1.0.75
[INFO] [stderr]     Checking serde_json v1.0.26
[INFO] [stderr]     Checking toy_blockchain v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 |     io::stdout().flush();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 |     io::stdin().read_line(&mut miner_address);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 |     io::stdout().flush();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:20:5
[INFO] [stderr]    |
[INFO] [stderr] 20 |     io::stdin().read_line(&mut difficulty);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:38:9
[INFO] [stderr]    |
[INFO] [stderr] 38 |         io::stdout().flush();
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:41:9
[INFO] [stderr]    |
[INFO] [stderr] 41 |         io::stdin().read_line(&mut choice);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:57:17
[INFO] [stderr]    |
[INFO] [stderr] 57 |                 io::stdout().flush();
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:58:17
[INFO] [stderr]    |
[INFO] [stderr] 58 |                 io::stdin().read_line(&mut sender);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:60:17
[INFO] [stderr]    |
[INFO] [stderr] 60 |                 io::stdout().flush();
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:61:17
[INFO] [stderr]    |
[INFO] [stderr] 61 |                 io::stdin().read_line(&mut receiver);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:63:17
[INFO] [stderr]    |
[INFO] [stderr] 63 |                 io::stdout().flush();
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:64:17
[INFO] [stderr]    |
[INFO] [stderr] 64 |                 io::stdin().read_line(&mut amount);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:90:17
[INFO] [stderr]    |
[INFO] [stderr] 90 |                 io::stdout().flush();
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:91:17
[INFO] [stderr]    |
[INFO] [stderr] 91 |                 io::stdin().read_line(&mut new_difficulty);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:105:17
[INFO] [stderr]     |
[INFO] [stderr] 105 |                 io::stdout().flush();
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:106:17
[INFO] [stderr]     |
[INFO] [stderr] 106 |                 io::stdin().read_line(&mut new_reward);
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 |     io::stdout().flush();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 |     io::stdin().read_line(&mut miner_address);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 |     io::stdout().flush();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:20:5
[INFO] [stderr]    |
[INFO] [stderr] 20 |     io::stdin().read_line(&mut difficulty);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:38:9
[INFO] [stderr]    |
[INFO] [stderr] 38 |         io::stdout().flush();
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:41:9
[INFO] [stderr]    |
[INFO] [stderr] 41 |         io::stdin().read_line(&mut choice);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:57:17
[INFO] [stderr]    |
[INFO] [stderr] 57 |                 io::stdout().flush();
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:58:17
[INFO] [stderr]    |
[INFO] [stderr] 58 |                 io::stdin().read_line(&mut sender);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:60:17
[INFO] [stderr]    |
[INFO] [stderr] 60 |                 io::stdout().flush();
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:61:17
[INFO] [stderr]    |
[INFO] [stderr] 61 |                 io::stdin().read_line(&mut receiver);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:63:17
[INFO] [stderr]    |
[INFO] [stderr] 63 |                 io::stdout().flush();
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:64:17
[INFO] [stderr]    |
[INFO] [stderr] 64 |                 io::stdin().read_line(&mut amount);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:90:17
[INFO] [stderr]    |
[INFO] [stderr] 90 |                 io::stdout().flush();
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:91:17
[INFO] [stderr]    |
[INFO] [stderr] 91 |                 io::stdin().read_line(&mut new_difficulty);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:105:17
[INFO] [stderr]     |
[INFO] [stderr] 105 |                 io::stdout().flush();
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:106:17
[INFO] [stderr]     |
[INFO] [stderr] 106 |                 io::stdin().read_line(&mut new_reward);
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 34.68s
[INFO] running `"docker" "inspect" "1ee4401fcf2e740b2a58ece2f4b933b9c3d9dfd8642fc8b16adf67848e12aa6c"`
[INFO] running `"docker" "rm" "-f" "1ee4401fcf2e740b2a58ece2f4b933b9c3d9dfd8642fc8b16adf67848e12aa6c"`
[INFO] [stdout] 1ee4401fcf2e740b2a58ece2f4b933b9c3d9dfd8642fc8b16adf67848e12aa6c