[INFO] fetching crate mprls 0.1.0...
[INFO] building mprls-0.1.0 against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] extracting crate mprls 0.1.0 into /workspace/builds/worker-1-tc1/source
[INFO] validating manifest of crates.io crate mprls 0.1.0 on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mprls 0.1.0
[INFO] finished tweaking crates.io crate mprls 0.1.0
[INFO] tweaked toml for crates.io crate mprls 0.1.0 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate crates.io crate mprls 0.1.0 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" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded linux-embedded-hal v0.3.0
[INFO] [stderr]   Downloaded ioctl-rs v0.1.6
[INFO] [stderr]   Downloaded serial-unix v0.4.0
[INFO] [stderr]   Downloaded serial-core v0.4.0
[INFO] [stderr]   Downloaded sysfs_gpio v0.5.4
[INFO] [stderr]   Downloaded i2cdev v0.4.4
[INFO] [stderr]   Downloaded termios v0.2.2
[INFO] [stderr]   Downloaded spidev v0.4.1
[INFO] [stderr]   Downloaded embedded-hal v0.2.6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ed9ad85eb373b8898f83e6dd905f189aae3397d3580fda7267f88af6707f8b02
[INFO] running `Command { std: "docker" "start" "-a" "ed9ad85eb373b8898f83e6dd905f189aae3397d3580fda7267f88af6707f8b02", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ed9ad85eb373b8898f83e6dd905f189aae3397d3580fda7267f88af6707f8b02", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ed9ad85eb373b8898f83e6dd905f189aae3397d3580fda7267f88af6707f8b02", kill_on_drop: false }`
[INFO] [stdout] ed9ad85eb373b8898f83e6dd905f189aae3397d3580fda7267f88af6707f8b02
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d784bc7f7b9878ebf8e723dfe48e58488be4c4e052840c553ee05dcd0b3eacd2
[INFO] running `Command { std: "docker" "start" "-a" "d784bc7f7b9878ebf8e723dfe48e58488be4c4e052840c553ee05dcd0b3eacd2", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.98
[INFO] [stderr]    Compiling semver v1.0.4
[INFO] [stderr]    Compiling nix v0.14.1
[INFO] [stderr]    Compiling nb v1.0.0
[INFO] [stderr]    Compiling nb v0.1.3
[INFO] [stderr]    Compiling embedded-hal v0.2.6
[INFO] [stderr]    Compiling rustc_version v0.4.0
[INFO] [stderr]    Compiling cast v0.2.7
[INFO] [stderr]    Compiling serial-core v0.4.0
[INFO] [stderr]    Compiling termios v0.2.2
[INFO] [stderr]    Compiling ioctl-rs v0.1.6
[INFO] [stderr]    Compiling serial-unix v0.4.0
[INFO] [stderr]    Compiling i2cdev v0.4.4
[INFO] [stderr]    Compiling spidev v0.4.1
[INFO] [stderr]    Compiling sysfs_gpio v0.5.4
[INFO] [stderr]    Compiling linux-embedded-hal v0.3.0
[INFO] [stderr]    Compiling mprls v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |         self.start_measurement();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 92 |         let _ = self.start_measurement();
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.65s
[INFO] running `Command { std: "docker" "inspect" "d784bc7f7b9878ebf8e723dfe48e58488be4c4e052840c553ee05dcd0b3eacd2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d784bc7f7b9878ebf8e723dfe48e58488be4c4e052840c553ee05dcd0b3eacd2", kill_on_drop: false }`
[INFO] [stdout] d784bc7f7b9878ebf8e723dfe48e58488be4c4e052840c553ee05dcd0b3eacd2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7cf6c75018934edb67e3f7277be6a24c5ee614296794193b65300da12af0b06e
[INFO] running `Command { std: "docker" "start" "-a" "7cf6c75018934edb67e3f7277be6a24c5ee614296794193b65300da12af0b06e", kill_on_drop: false }`
[INFO] [stderr]    Compiling mprls v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |         self.start_measurement();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 92 |         let _ = self.start_measurement();
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |         self.start_measurement();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 92 |         let _ = self.start_measurement();
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.14s
[INFO] running `Command { std: "docker" "inspect" "7cf6c75018934edb67e3f7277be6a24c5ee614296794193b65300da12af0b06e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7cf6c75018934edb67e3f7277be6a24c5ee614296794193b65300da12af0b06e", kill_on_drop: false }`
[INFO] [stdout] 7cf6c75018934edb67e3f7277be6a24c5ee614296794193b65300da12af0b06e