[INFO] fetching crate fast-str 1.0.0...
[INFO] checking fast-str-1.0.0 against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] extracting crate fast-str 1.0.0 into /workspace/builds/worker-0-tc2/source
[INFO] started tweaking crates.io crate fast-str 1.0.0
[INFO] finished tweaking crates.io crate fast-str 1.0.0
[INFO] tweaked toml for crates.io crate fast-str 1.0.0 written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate fast-str 1.0.0 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 229 packages to latest compatible versions
[INFO] [stderr]       Adding criterion v0.4.0 (available: v0.7.0)
[INFO] [stderr]       Adding generic-array v0.14.7 (available: v0.14.9)
[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] [stderr]     Blocking waiting for file lock on package cache
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ad3df65d7cec1cbbb577c5e578044bc1ab600af8cbb7e494dc31ae64e72e43b7
[INFO] running `Command { std: "docker" "start" "-a" "ad3df65d7cec1cbbb577c5e578044bc1ab600af8cbb7e494dc31ae64e72e43b7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ad3df65d7cec1cbbb577c5e578044bc1ab600af8cbb7e494dc31ae64e72e43b7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ad3df65d7cec1cbbb577c5e578044bc1ab600af8cbb7e494dc31ae64e72e43b7", kill_on_drop: false }`
[INFO] [stdout] ad3df65d7cec1cbbb577c5e578044bc1ab600af8cbb7e494dc31ae64e72e43b7
[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 -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] e9d184fc1544ac083314afb45ea2451952eeb7ed63313cd3719419839b7e66b0
[INFO] running `Command { std: "docker" "start" "-a" "e9d184fc1544ac083314afb45ea2451952eeb7ed63313cd3719419839b7e66b0", kill_on_drop: false }`
[INFO] [stderr]    Compiling zerocopy-derive v0.8.27
[INFO] [stderr]    Compiling serde_derive v1.0.228
[INFO] [stderr]     Checking fast-str v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait `DoubleEndedSearcher` is never used
[INFO] [stdout]    --> src/pattern/mod.rs:340:11
[INFO] [stdout]     |
[INFO] [stdout] 340 | pub trait DoubleEndedSearcher<'a>: ReverseSearcher<'a> {}
[INFO] [stdout]     |           ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<FastStr, Infallible>
[INFO] [stdout]     --> src/backend/mod.rs:1054:53
[INFO] [stdout]      |
[INFO] [stdout] 1054 |       fn from_str(s: &str) -> Result<Self, Self::Err> {
[INFO] [stdout]      |  _____________________________________________________^
[INFO] [stdout] 1055 | |         let result = FromStr::from_str(s);
[INFO] [stdout] 1056 | |         match result {
[INFO] [stdout] 1057 | |             Ok(ok) => Ok(Self::from_string(ok)),
[INFO] [stdout] ...    |
[INFO] [stdout] 1060 | |     }
[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<String, Infallible>
[INFO] [stdout]     --> src/backend/mod.rs:1055:22
[INFO] [stdout]      |
[INFO] [stdout] 1055 |         let result = FromStr::from_str(s);
[INFO] [stdout]      |                      ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<FastStr, Infallible>
[INFO] [stdout]     --> src/backend/mod.rs:1056:9
[INFO] [stdout]      |
[INFO] [stdout] 1056 | /         match result {
[INFO] [stdout] 1057 | |             Ok(ok) => Ok(Self::from_string(ok)),
[INFO] [stdout] 1058 | |             Err(err) => Err(err),
[INFO] [stdout] 1059 | |         }
[INFO] [stdout]      | |_________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]     --> src/backend/mod.rs:1056:15
[INFO] [stdout]      |
[INFO] [stdout] 1056 |         match result {
[INFO] [stdout]      |               ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<FastStr, Infallible>
[INFO] [stdout]     --> src/backend/mod.rs:1057:23
[INFO] [stdout]      |
[INFO] [stdout] 1057 |             Ok(ok) => Ok(Self::from_string(ok)),
[INFO] [stdout]      |                       ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<FastStr, Infallible>
[INFO] [stdout]     --> src/backend/mod.rs:1058:25
[INFO] [stdout]      |
[INFO] [stdout] 1058 |             Err(err) => Err(err),
[INFO] [stdout]      |                         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `fast-str` (lib) due to 6 previous errors; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "e9d184fc1544ac083314afb45ea2451952eeb7ed63313cd3719419839b7e66b0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e9d184fc1544ac083314afb45ea2451952eeb7ed63313cd3719419839b7e66b0", kill_on_drop: false }`
[INFO] [stdout] e9d184fc1544ac083314afb45ea2451952eeb7ed63313cd3719419839b7e66b0
