[INFO] cloning repository https://github.com/akashkb-a01/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/akashkb-a01/rust-blockchain" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fakashkb-a01%2Frust-blockchain", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fakashkb-a01%2Frust-blockchain'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 36e6c1691751576f3622a40a2c552f515f9a4434
[INFO] checking akashkb-a01/rust-blockchain against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fakashkb-a01%2Frust-blockchain" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/akashkb-a01/rust-blockchain on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/akashkb-a01/rust-blockchain
[INFO] finished tweaking git repo https://github.com/akashkb-a01/rust-blockchain
[INFO] tweaked toml for git repo https://github.com/akashkb-a01/rust-blockchain written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/akashkb-a01/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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded crypto-common v0.1.1
[INFO] [stderr]   Downloaded block-buffer v0.10.0
[INFO] [stderr]   Downloaded digest v0.10.1
[INFO] [stderr]   Downloaded sha2 v0.10.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6dc99849f7694f10e816e8fe7f504af2e0b58ba2ded17f89c5b9afa166e2e5ef
[INFO] running `Command { std: "docker" "start" "-a" "6dc99849f7694f10e816e8fe7f504af2e0b58ba2ded17f89c5b9afa166e2e5ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6dc99849f7694f10e816e8fe7f504af2e0b58ba2ded17f89c5b9afa166e2e5ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6dc99849f7694f10e816e8fe7f504af2e0b58ba2ded17f89c5b9afa166e2e5ef", kill_on_drop: false }`
[INFO] [stdout] 6dc99849f7694f10e816e8fe7f504af2e0b58ba2ded17f89c5b9afa166e2e5ef
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/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" "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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 74bfab1491898a5d603cf547efbdaf35c18ff37cda3378794301699378d4c86f
[INFO] running `Command { std: "docker" "start" "-a" "74bfab1491898a5d603cf547efbdaf35c18ff37cda3378794301699378d4c86f", kill_on_drop: false }`
[INFO] [stderr]    Compiling typenum v1.15.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.36
[INFO] [stderr]    Compiling syn v1.0.84
[INFO] [stderr]    Compiling libc v0.2.112
[INFO] [stderr]    Compiling serde_derive v1.0.132
[INFO] [stderr]    Compiling serde v1.0.132
[INFO] [stderr]    Compiling serde_json v1.0.73
[INFO] [stderr]     Checking itoa v1.0.1
[INFO] [stderr]     Checking ryu v1.0.9
[INFO] [stderr]    Compiling generic-array v0.14.4
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]    Compiling quote v1.0.14
[INFO] [stderr]     Checking chrono v0.4.19
[INFO] [stderr]     Checking crypto-common v0.1.1
[INFO] [stderr]     Checking block-buffer v0.10.0
[INFO] [stderr]     Checking digest v0.10.1
[INFO] [stderr]     Checking sha2 v0.10.0
[INFO] [stderr]     Checking pow-blockchain v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `genesis_block` is never read
[INFO] [stdout]   --> src/models/blockchain.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 8  | pub struct Blockchain {
[INFO] [stdout]    |            ---------- field in this struct
[INFO] [stdout] 9  |     // The first block to be added to the chain.
[INFO] [stdout] 10 |     pub genesis_block: Block,
[INFO] [stdout]    |         ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Blockchain` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `genesis_block` is never read
[INFO] [stdout]   --> src/models/blockchain.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 8  | pub struct Blockchain {
[INFO] [stdout]    |            ---------- field in this struct
[INFO] [stdout] 9  |     // The first block to be added to the chain.
[INFO] [stdout] 10 |     pub genesis_block: Block,
[INFO] [stdout]    |         ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Blockchain` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 18.03s
[INFO] running `Command { std: "docker" "inspect" "74bfab1491898a5d603cf547efbdaf35c18ff37cda3378794301699378d4c86f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "74bfab1491898a5d603cf547efbdaf35c18ff37cda3378794301699378d4c86f", kill_on_drop: false }`
[INFO] [stdout] 74bfab1491898a5d603cf547efbdaf35c18ff37cda3378794301699378d4c86f
[INFO] checking akashkb-a01/rust-blockchain against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fakashkb-a01%2Frust-blockchain" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/akashkb-a01/rust-blockchain on toolchain 2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/akashkb-a01/rust-blockchain
[INFO] finished tweaking git repo https://github.com/akashkb-a01/rust-blockchain
[INFO] tweaked toml for git repo https://github.com/akashkb-a01/rust-blockchain written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/akashkb-a01/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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4cdc764bbd7a9796cfba762b055062f1a32b4272d86a543a0ab37fb21bd2d0fe
[INFO] running `Command { std: "docker" "start" "-a" "4cdc764bbd7a9796cfba762b055062f1a32b4272d86a543a0ab37fb21bd2d0fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4cdc764bbd7a9796cfba762b055062f1a32b4272d86a543a0ab37fb21bd2d0fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4cdc764bbd7a9796cfba762b055062f1a32b4272d86a543a0ab37fb21bd2d0fe", kill_on_drop: false }`
[INFO] [stdout] 4cdc764bbd7a9796cfba762b055062f1a32b4272d86a543a0ab37fb21bd2d0fe
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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" "-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1975b80be24c266eb9d39909d143b0c56cd5ff148cb68a8d56893ec3afb0562a
[INFO] running `Command { std: "docker" "start" "-a" "1975b80be24c266eb9d39909d143b0c56cd5ff148cb68a8d56893ec3afb0562a", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.36
[INFO] [stderr]    Compiling typenum v1.15.0
[INFO] [stderr]    Compiling generic-array v0.14.4
[INFO] [stderr]    Compiling syn v1.0.84
[INFO] [stderr]    Compiling serde_derive v1.0.132
[INFO] [stderr]    Compiling libc v0.2.112
[INFO] [stderr]    Compiling serde v1.0.132
[INFO] [stderr]    Compiling serde_json v1.0.73
[INFO] [stderr]     Checking ryu v1.0.9
[INFO] [stderr]     Checking itoa v1.0.1
[INFO] [stderr]    Compiling quote v1.0.14
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking chrono v0.4.19
[INFO] [stderr]     Checking block-buffer v0.10.0
[INFO] [stderr]     Checking crypto-common v0.1.1
[INFO] [stderr]     Checking digest v0.10.1
[INFO] [stderr]     Checking sha2 v0.10.0
[INFO] [stderr]     Checking pow-blockchain v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `genesis_block` is never read
[INFO] [stdout]   --> src/models/blockchain.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 8  | pub struct Blockchain {
[INFO] [stdout]    |            ---------- field in this struct
[INFO] [stdout] 9  |     // The first block to be added to the chain.
[INFO] [stdout] 10 |     pub genesis_block: Block,
[INFO] [stdout]    |         ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Blockchain` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `genesis_block` is never read
[INFO] [stdout]   --> src/models/blockchain.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 8  | pub struct Blockchain {
[INFO] [stdout]    |            ---------- field in this struct
[INFO] [stdout] 9  |     // The first block to be added to the chain.
[INFO] [stdout] 10 |     pub genesis_block: Block,
[INFO] [stdout]    |         ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Blockchain` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 17.43s
[INFO] running `Command { std: "docker" "inspect" "1975b80be24c266eb9d39909d143b0c56cd5ff148cb68a8d56893ec3afb0562a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1975b80be24c266eb9d39909d143b0c56cd5ff148cb68a8d56893ec3afb0562a", kill_on_drop: false }`
[INFO] [stdout] 1975b80be24c266eb9d39909d143b0c56cd5ff148cb68a8d56893ec3afb0562a