[INFO] fetching crate mccs 0.2.0...
[INFO] checking mccs-0.2.0 against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] extracting crate mccs 0.2.0 into /workspace/builds/worker-4-tc2/source
[INFO] started tweaking crates.io crate mccs 0.2.0
[INFO] finished tweaking crates.io crate mccs 0.2.0
[INFO] tweaked toml for crates.io crate mccs 0.2.0 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate mccs 0.2.0 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] 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-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 3a6ebc392f24ad57b14b2caf7032468663af39a25201772f0f2755971aff4048
[INFO] running `Command { std: "docker" "start" "-a" "3a6ebc392f24ad57b14b2caf7032468663af39a25201772f0f2755971aff4048", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3a6ebc392f24ad57b14b2caf7032468663af39a25201772f0f2755971aff4048", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3a6ebc392f24ad57b14b2caf7032468663af39a25201772f0f2755971aff4048", kill_on_drop: false }`
[INFO] [stdout] 3a6ebc392f24ad57b14b2caf7032468663af39a25201772f0f2755971aff4048
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 8e942bd63f75c6d2f06f9e8a2a5c8af43183d7f49916c899660b5ae8273a8ca2
[INFO] running `Command { std: "docker" "start" "-a" "8e942bd63f75c6d2f06f9e8a2a5c8af43183d7f49916c899660b5ae8273a8ca2", kill_on_drop: false }`
[INFO] [stderr]     Checking mccs v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: this type will no longer be must used: Result<Protocol, Infallible>
[INFO] [stdout]    --> src/lib.rs:169:53
[INFO] [stdout]     |
[INFO] [stdout] 169 |       fn from_str(s: &str) -> Result<Self, Self::Err> {
[INFO] [stdout]     |  _____________________________________________________^
[INFO] [stdout] 170 | |         Ok(s.into())
[INFO] [stdout] 171 | |     }
[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<Protocol, Infallible>
[INFO] [stdout]    --> src/lib.rs:170:9
[INFO] [stdout]     |
[INFO] [stdout] 170 |         Ok(s.into())
[INFO] [stdout]     |         ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Type, Infallible>
[INFO] [stdout]    --> src/lib.rs:215:53
[INFO] [stdout]     |
[INFO] [stdout] 215 |       fn from_str(s: &str) -> Result<Self, Self::Err> {
[INFO] [stdout]     |  _____________________________________________________^
[INFO] [stdout] 216 | |         Ok(s.into())
[INFO] [stdout] 217 | |     }
[INFO] [stdout]     | |_____^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Type, Infallible>
[INFO] [stdout]    --> src/lib.rs:216:9
[INFO] [stdout]     |
[INFO] [stdout] 216 |         Ok(s.into())
[INFO] [stdout]     |         ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Protocol, Infallible>
[INFO] [stdout]    --> src/lib.rs:169:53
[INFO] [stdout]     |
[INFO] [stdout] 169 |       fn from_str(s: &str) -> Result<Self, Self::Err> {
[INFO] [stdout]     |  _____________________________________________________^
[INFO] [stdout] 170 | |         Ok(s.into())
[INFO] [stdout] 171 | |     }
[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<Protocol, Infallible>
[INFO] [stdout]    --> src/lib.rs:170:9
[INFO] [stdout]     |
[INFO] [stdout] 170 |         Ok(s.into())
[INFO] [stdout]     |         ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Type, Infallible>
[INFO] [stdout]    --> src/lib.rs:215:53
[INFO] [stdout]     |
[INFO] [stdout] 215 |       fn from_str(s: &str) -> Result<Self, Self::Err> {
[INFO] [stdout]     |  _____________________________________________________^
[INFO] [stdout] 216 | |         Ok(s.into())
[INFO] [stdout] 217 | |     }
[INFO] [stdout]     | |_____^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<Type, Infallible>
[INFO] [stdout]    --> src/lib.rs:216:9
[INFO] [stdout]     |
[INFO] [stdout] 216 |         Ok(s.into())
[INFO] [stdout]     |         ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/lib.rs:255:19
[INFO] [stdout]     |
[INFO] [stdout] 255 |     pub fn values(&self) -> btree_map::Keys<u8, Option<String>> {
[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] 255 |     pub fn values(&self) -> btree_map::Keys<'_, u8, Option<String>> {
[INFO] [stdout]     |                                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/lib.rs:255:19
[INFO] [stdout]     |
[INFO] [stdout] 255 |     pub fn values(&self) -> btree_map::Keys<u8, Option<String>> {
[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] 255 |     pub fn values(&self) -> btree_map::Keys<'_, u8, Option<String>> {
[INFO] [stdout]     |                                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `mccs` (lib) due to 4 previous errors; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `mccs` (lib test) due to 4 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "8e942bd63f75c6d2f06f9e8a2a5c8af43183d7f49916c899660b5ae8273a8ca2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8e942bd63f75c6d2f06f9e8a2a5c8af43183d7f49916c899660b5ae8273a8ca2", kill_on_drop: false }`
[INFO] [stdout] 8e942bd63f75c6d2f06f9e8a2a5c8af43183d7f49916c899660b5ae8273a8ca2
