[INFO] fetching crate mirai_rs 0.1.1...
[INFO] checking mirai_rs-0.1.1 against 1.55.0 for beta-1.56-3
[INFO] extracting crate mirai_rs 0.1.1 into /workspace/builds/worker-100/source
[INFO] validating manifest of crates.io crate mirai_rs 0.1.1 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mirai_rs 0.1.1
[INFO] finished tweaking crates.io crate mirai_rs 0.1.1
[INFO] tweaked toml for crates.io crate mirai_rs 0.1.1 written to /workspace/builds/worker-100/source/Cargo.toml
[INFO] crate crates.io crate mirai_rs 0.1.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "rm" "-f" "8f4f9b8fb3e834eef947c66b91f02ac75dea064d253a12ea89b6672b6731dbf0", kill_on_drop: false }`
[INFO] [stdout] 8f4f9b8fb3e834eef947c66b91f02ac75dea064d253a12ea89b6672b6731dbf0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-100/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-100/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=warn" "-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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 897f07f167a733ebe7a9229e0ccea6e20550fcef99e0dadea3727532d218d663
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[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]    --> src/session.rs:134:11
[INFO] [stdout]     |
[INFO] [stdout] 134 |         #[serde(rename_all = "camelCase")]
[INFO] [stdout]     |           ^^^^^
[INFO] [stdout] 135 |         #[derive(Serialize)]
[INFO] [stdout]     |                  --------- the attribute is introduced here
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(legacy_derive_helpers)]` on by default
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/event.rs:21:3
[INFO] [stdout]    |
[INFO] [stdout] 21 | #[serde(tag = "type")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 22 | #[derive(Debug, Clone, Deserialize)]
[INFO] [stdout]    |                        ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/event.rs:37:3
[INFO] [stdout]    |
[INFO] [stdout] 37 | #[serde(tag = "type")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 38 | #[derive(Clone, Debug, Deserialize)]
[INFO] [stdout]    |                        ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/event.rs:89:3
[INFO] [stdout]    |
[INFO] [stdout] 89 | #[serde(tag = "type")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 90 | #[derive(Clone, Debug, Deserialize)]
[INFO] [stdout]    |                        ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]    --> src/message/event.rs:111:3
[INFO] [stdout]     |
[INFO] [stdout] 111 | #[serde(untagged)]
[INFO] [stdout]     |   ^^^^^
[INFO] [stdout] 112 | #[derive(Clone, Debug, Deserialize)]
[INFO] [stdout]     |                        ----------- the attribute is introduced here
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]    --> src/message/event.rs:134:3
[INFO] [stdout]     |
[INFO] [stdout] 134 | #[serde(untagged)]
[INFO] [stdout]     |   ^^^^^
[INFO] [stdout] 135 | #[derive(Debug, Clone, Deserialize)]
[INFO] [stdout]     |                        ----------- the attribute is introduced here
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/single.rs:26:3
[INFO] [stdout]    |
[INFO] [stdout] 26 | #[serde(tag = "type")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 27 | #[derive(Debug, Clone, Deserialize, Serialize)]
[INFO] [stdout]    |                        ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/send.rs:11:3
[INFO] [stdout]    |
[INFO] [stdout] 11 | #[serde(rename_all = "camelCase")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 12 | #[derive(Serialize)]
[INFO] [stdout]    |          --------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/send.rs:21:3
[INFO] [stdout]    |
[INFO] [stdout] 21 | #[serde(rename_all = "camelCase")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 22 | #[derive(Deserialize)]
[INFO] [stdout]    |          ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]    --> src/session.rs:134:11
[INFO] [stdout]     |
[INFO] [stdout] 134 |         #[serde(rename_all = "camelCase")]
[INFO] [stdout]     |           ^^^^^
[INFO] [stdout] 135 |         #[derive(Serialize)]
[INFO] [stdout]     |                  --------- the attribute is introduced here
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(legacy_derive_helpers)]` on by default
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/event.rs:21:3
[INFO] [stdout]    |
[INFO] [stdout] 21 | #[serde(tag = "type")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 22 | #[derive(Debug, Clone, Deserialize)]
[INFO] [stdout]    |                        ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/event.rs:37:3
[INFO] [stdout]    |
[INFO] [stdout] 37 | #[serde(tag = "type")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 38 | #[derive(Clone, Debug, Deserialize)]
[INFO] [stdout]    |                        ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/event.rs:89:3
[INFO] [stdout]    |
[INFO] [stdout] 89 | #[serde(tag = "type")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 90 | #[derive(Clone, Debug, Deserialize)]
[INFO] [stdout]    |                        ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]    --> src/message/event.rs:111:3
[INFO] [stdout]     |
[INFO] [stdout] 111 | #[serde(untagged)]
[INFO] [stdout]     |   ^^^^^
[INFO] [stdout] 112 | #[derive(Clone, Debug, Deserialize)]
[INFO] [stdout]     |                        ----------- the attribute is introduced here
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]    --> src/message/event.rs:134:3
[INFO] [stdout]     |
[INFO] [stdout] 134 | #[serde(untagged)]
[INFO] [stdout]     |   ^^^^^
[INFO] [stdout] 135 | #[derive(Debug, Clone, Deserialize)]
[INFO] [stdout]     |                        ----------- the attribute is introduced here
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/single.rs:26:3
[INFO] [stdout]    |
[INFO] [stdout] 26 | #[serde(tag = "type")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 27 | #[derive(Debug, Clone, Deserialize, Serialize)]
[INFO] [stdout]    |                        ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/send.rs:11:3
[INFO] [stdout]    |
[INFO] [stdout] 11 | #[serde(rename_all = "camelCase")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 12 | #[derive(Serialize)]
[INFO] [stdout]    |          --------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: derive helper attribute is used before it is introduced
[INFO] [stdout]   --> src/message/send.rs:21:3
[INFO] [stdout]    |
[INFO] [stdout] 21 | #[serde(rename_all = "camelCase")]
[INFO] [stdout]    |   ^^^^^
[INFO] [stdout] 22 | #[derive(Deserialize)]
[INFO] [stdout]    |          ----------- the attribute is introduced here
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #79202 <https://github.com/rust-lang/rust/issues/79202>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `msg`
[INFO] [stdout]   --> src/session.rs:69:5
[INFO] [stdout]    |
[INFO] [stdout] 69 |     pub msg: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `msg`
[INFO] [stdout]   --> src/session.rs:69:5
[INFO] [stdout]    |
[INFO] [stdout] 69 |     pub msg: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/subscribe.rs:29:33
[INFO] [stdout]    |
[INFO] [stdout] 29 | ...                   subscriber.send(mp.clone());            // TODO: use Result
[INFO] [stdout]    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 39.36s
[INFO] running `Command { std: "docker" "inspect" "897f07f167a733ebe7a9229e0ccea6e20550fcef99e0dadea3727532d218d663", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "897f07f167a733ebe7a9229e0ccea6e20550fcef99e0dadea3727532d218d663", kill_on_drop: false }`
[INFO] [stdout] 897f07f167a733ebe7a9229e0ccea6e20550fcef99e0dadea3727532d218d663
