[INFO] fetching crate blockchain 0.9.2...
[INFO] checking blockchain-0.9.2 against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] extracting crate blockchain 0.9.2 into /workspace/builds/worker-2-tc2/source
[INFO] started tweaking crates.io crate blockchain 0.9.2
[INFO] finished tweaking crates.io crate blockchain 0.9.2
[INFO] tweaked toml for crates.io crate blockchain 0.9.2 written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate blockchain 0.9.2 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] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 1 package to latest compatible version
[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-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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] 0db29e6747a5032c4216e852f8f50844057dff7fe6e0900663fe07774388c6f8
[INFO] running `Command { std: "docker" "start" "-a" "0db29e6747a5032c4216e852f8f50844057dff7fe6e0900663fe07774388c6f8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0db29e6747a5032c4216e852f8f50844057dff7fe6e0900663fe07774388c6f8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0db29e6747a5032c4216e852f8f50844057dff7fe6e0900663fe07774388c6f8", kill_on_drop: false }`
[INFO] [stdout] 0db29e6747a5032c4216e852f8f50844057dff7fe6e0900663fe07774388c6f8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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] 38f07bbdb84a8a8e344a9236c338df281a04f2af56bfdb9be1338f2591a8c0c1
[INFO] running `Command { std: "docker" "start" "-a" "38f07bbdb84a8a8e344a9236c338df281a04f2af56bfdb9be1338f2591a8c0c1", kill_on_drop: false }`
[INFO] [stderr]     Checking blockchain-core v0.1.2
[INFO] [stderr]     Checking blockchain v0.9.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> src/backend/mod.rs:33:14
[INFO] [stdout]    |
[INFO] [stdout] 33 |     pub fn lock(&self) -> MutexGuard<()> {
[INFO] [stdout]    |                 ^^^^^     ^^^^^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]    |                 |
[INFO] [stdout]    |                 the lifetime is elided here
[INFO] [stdout]    |
[INFO] [stdout]    = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]    |
[INFO] [stdout] 33 |     pub fn lock(&self) -> MutexGuard<'_, ()> {
[INFO] [stdout]    |                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Option<Vec<u8>>, Infallible>
[INFO] [stdout]   --> src/backend/state.rs:33:76
[INFO] [stdout]    |
[INFO] [stdout] 33 |       fn read_storage(&self, key: &[u8]) -> Result<Option<Vec<u8>>, Infallible> {
[INFO] [stdout]    |  _______________________________________________________________________________^
[INFO] [stdout] 34 | |         Ok(self.storage.get(key).map(|value| value.to_vec()))
[INFO] [stdout] 35 | |     }
[INFO] [stdout]    | |_____^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Option<Vec<u8>>, Infallible>
[INFO] [stdout]   --> src/backend/state.rs:34:3
[INFO] [stdout]    |
[INFO] [stdout] 34 |         Ok(self.storage.get(key).map(|value| value.to_vec()))
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `blockchain` (lib) due to 2 previous errors; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> src/backend/mod.rs:33:14
[INFO] [stdout]    |
[INFO] [stdout] 33 |     pub fn lock(&self) -> MutexGuard<()> {
[INFO] [stdout]    |                 ^^^^^     ^^^^^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]    |                 |
[INFO] [stdout]    |                 the lifetime is elided here
[INFO] [stdout]    |
[INFO] [stdout]    = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]    |
[INFO] [stdout] 33 |     pub fn lock(&self) -> MutexGuard<'_, ()> {
[INFO] [stdout]    |                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Option<Vec<u8>>, Infallible>
[INFO] [stdout]   --> src/backend/state.rs:33:76
[INFO] [stdout]    |
[INFO] [stdout] 33 |       fn read_storage(&self, key: &[u8]) -> Result<Option<Vec<u8>>, Infallible> {
[INFO] [stdout]    |  _______________________________________________________________________________^
[INFO] [stdout] 34 | |         Ok(self.storage.get(key).map(|value| value.to_vec()))
[INFO] [stdout] 35 | |     }
[INFO] [stdout]    | |_____^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Option<Vec<u8>>, Infallible>
[INFO] [stdout]   --> src/backend/state.rs:34:3
[INFO] [stdout]    |
[INFO] [stdout] 34 |         Ok(self.storage.get(key).map(|value| value.to_vec()))
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `blockchain` (lib test) due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "38f07bbdb84a8a8e344a9236c338df281a04f2af56bfdb9be1338f2591a8c0c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "38f07bbdb84a8a8e344a9236c338df281a04f2af56bfdb9be1338f2591a8c0c1", kill_on_drop: false }`
[INFO] [stdout] 38f07bbdb84a8a8e344a9236c338df281a04f2af56bfdb9be1338f2591a8c0c1