[INFO] fetching crate mpu6050 0.1.3...
[INFO] testing mpu6050-0.1.3 against beta-2020-10-09 for beta-1.48-1
[INFO] extracting crate mpu6050 0.1.3 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate mpu6050 0.1.3 on toolchain beta-2020-10-09
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-9/source/.cargo/config
[INFO] started tweaking crates.io crate mpu6050 0.1.3
[INFO] finished tweaking crates.io crate mpu6050 0.1.3
[INFO] tweaked toml for crates.io crate mpu6050 0.1.3 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded libm v0.1.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2cf1ee7d6ef48316c06937678909deedc7a0a752adaef7de2c8abd6540a3ce2a
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "2cf1ee7d6ef48316c06937678909deedc7a0a752adaef7de2c8abd6540a3ce2a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2cf1ee7d6ef48316c06937678909deedc7a0a752adaef7de2c8abd6540a3ce2a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2cf1ee7d6ef48316c06937678909deedc7a0a752adaef7de2c8abd6540a3ce2a", kill_on_drop: false }`
[INFO] [stdout] 2cf1ee7d6ef48316c06937678909deedc7a0a752adaef7de2c8abd6540a3ce2a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 756f1946c2d7c486c2e5148a367f99c00e6323af53d1378ada5bafe9853c9857
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "756f1946c2d7c486c2e5148a367f99c00e6323af53d1378ada5bafe9853c9857", kill_on_drop: false }`
[INFO] [stderr]    Compiling libm v0.1.4
[INFO] [stderr]    Compiling embedded-hal v0.2.4
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling alga v0.9.3
[INFO] [stderr]    Compiling nalgebra v0.18.1
[INFO] [stderr]    Compiling mpu6050 v0.1.3 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 21.31s
[INFO] running `Command { std: "docker" "inspect" "756f1946c2d7c486c2e5148a367f99c00e6323af53d1378ada5bafe9853c9857", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "756f1946c2d7c486c2e5148a367f99c00e6323af53d1378ada5bafe9853c9857", kill_on_drop: false }`
[INFO] [stdout] 756f1946c2d7c486c2e5148a367f99c00e6323af53d1378ada5bafe9853c9857
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c7bd56bd6389222f6be9b5a7fac61f7a3a15e263eb6259f04373b255ead187ab
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "c7bd56bd6389222f6be9b5a7fac61f7a3a15e263eb6259f04373b255ead187ab", kill_on_drop: false }`
[INFO] [stderr]    Compiling bitflags v0.3.3
[INFO] [stderr]    Compiling nix v0.6.0
[INFO] [stderr]    Compiling i2cdev v0.4.4
[INFO] [stderr]    Compiling sysfs_gpio v0.5.4
[INFO] [stderr]    Compiling spidev v0.3.0
[INFO] [stderr]    Compiling linux-embedded-hal v0.2.2
[INFO] [stderr]    Compiling mpu6050 v0.1.3 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 8.73s
[INFO] running `Command { std: "docker" "inspect" "c7bd56bd6389222f6be9b5a7fac61f7a3a15e263eb6259f04373b255ead187ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c7bd56bd6389222f6be9b5a7fac61f7a3a15e263eb6259f04373b255ead187ab", kill_on_drop: false }`
[INFO] [stdout] c7bd56bd6389222f6be9b5a7fac61f7a3a15e263eb6259f04373b255ead187ab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 4f734db7070352ac0b832562297ebc646901116f6e8b18a08940ba9d7d7cde76
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "4f734db7070352ac0b832562297ebc646901116f6e8b18a08940ba9d7d7cde76", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.16s
[INFO] [stdout] running 2 tests
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/mpu6050-58ee7d3500e4b07c
[INFO] [stdout] test tests::test_unit_conv ... ok
[INFO] [stderr]    Doc-tests mpu6050
[INFO] [stdout] test tests::test_nalgebra ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stderr] error: test failed, to rerun pass '--doc'
[INFO] [stdout] test src/lib.rs - (line 7) ... FAILED
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- src/lib.rs - (line 7) stdout ----
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `Mpu6050Error`
[INFO] [stdout]  --> src/lib.rs:9:14
[INFO] [stdout]   |
[INFO] [stdout] 4 |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout]   |              ^^^^^^^^^^^^ use of undeclared type `Mpu6050Error`
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `I2cdev`
[INFO] [stdout]  --> src/lib.rs:8:11
[INFO] [stdout]   |
[INFO] [stdout] 3 | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout]   |           ^^^^^^ not found in this scope
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this struct
[INFO] [stdout]   |
[INFO] [stdout] 2 | use linux_embedded_hal::I2cdev;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find value `Delay` in this scope
[INFO] [stdout]  --> src/lib.rs:11:13
[INFO] [stdout]   |
[INFO] [stdout] 6 | let delay = Delay;
[INFO] [stdout]   |             ^^^^^ not found in this scope
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this unit struct
[INFO] [stdout]   |
[INFO] [stdout] 2 | use linux_embedded_hal::Delay;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `Mpu6050`
[INFO] [stdout]  --> src/lib.rs:13:15
[INFO] [stdout]   |
[INFO] [stdout] 8 | let mut mpu = Mpu6050::new(i2c, delay);
[INFO] [stdout]   |               ^^^^^^^ not found in this scope
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this struct
[INFO] [stdout]   |
[INFO] [stdout] 2 | use mpu6050::Mpu6050;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find function, tuple struct or tuple variant `Steps` in this scope
[INFO] [stdout]   --> src/lib.rs:15:16
[INFO] [stdout]    |
[INFO] [stdout] 10 | mpu.soft_calib(Steps(100))?;
[INFO] [stdout]    |                ^^^^^ not found in this scope
[INFO] [stdout]    |
[INFO] [stdout] help: consider importing this tuple struct
[INFO] [stdout]    |
[INFO] [stdout] 2  | use mpu6050::Steps;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find function, tuple struct or tuple variant `Steps` in this scope
[INFO] [stdout]   --> src/lib.rs:16:19
[INFO] [stdout]    |
[INFO] [stdout] 11 | mpu.calc_variance(Steps(50))?;
[INFO] [stdout]    |                   ^^^^^ not found in this scope
[INFO] [stdout]    |
[INFO] [stdout] help: consider importing this tuple struct
[INFO] [stdout]    |
[INFO] [stdout] 2  | use mpu6050::Steps;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find function, tuple struct or tuple variant `Steps` in this scope
[INFO] [stdout]   --> src/lib.rs:25:34
[INFO] [stdout]    |
[INFO] [stdout] 20 | let acc = mpu.get_acc_angles_avg(Steps(5))?;
[INFO] [stdout]    |                                  ^^^^^ not found in this scope
[INFO] [stdout]    |
[INFO] [stdout] help: consider importing this tuple struct
[INFO] [stdout]    |
[INFO] [stdout] 2  | use mpu6050::Steps;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find function, tuple struct or tuple variant `Steps` in this scope
[INFO] [stdout]   --> src/lib.rs:31:29
[INFO] [stdout]    |
[INFO] [stdout] 26 | let temp = mpu.get_temp_avg(Steps(5))?;
[INFO] [stdout]    |                             ^^^^^ not found in this scope
[INFO] [stdout]    |
[INFO] [stdout] help: consider importing this tuple struct
[INFO] [stdout]    |
[INFO] [stdout] 2  | use mpu6050::Steps;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find function, tuple struct or tuple variant `Steps` in this scope
[INFO] [stdout]   --> src/lib.rs:37:29
[INFO] [stdout]    |
[INFO] [stdout] 32 | let gyro = mpu.get_gyro_avg(Steps(5))?;
[INFO] [stdout]    |                             ^^^^^ not found in this scope
[INFO] [stdout]    |
[INFO] [stdout] help: consider importing this tuple struct
[INFO] [stdout]    |
[INFO] [stdout] 2  | use mpu6050::Steps;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find function, tuple struct or tuple variant `Steps` in this scope
[INFO] [stdout]   --> src/lib.rs:43:27
[INFO] [stdout]    |
[INFO] [stdout] 38 | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout]    |                           ^^^^^ not found in this scope
[INFO] [stdout]    |
[INFO] [stdout] help: consider importing this tuple struct
[INFO] [stdout]    |
[INFO] [stdout] 2  | use mpu6050::Steps;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:8:11
[INFO] [stdout]    |
[INFO] [stdout] 2  |  / fn main() {
[INFO] [stdout] 3  |  | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout]    |  |___________^
[INFO] [stdout] 4  | ||     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout]    | ||________________________________^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 5  |  |
[INFO] [stdout] ...   |
[INFO] [stdout] 38 |  | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 |  | }
[INFO] [stdout]    |  |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:14:1
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 9  | | mpu.init()?;
[INFO] [stdout]    | | ^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:15:1
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 10 | | mpu.soft_calib(Steps(100))?;
[INFO] [stdout]    | | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:16:1
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 11 | | mpu.calc_variance(Steps(50))?;
[INFO] [stdout]    | | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:22:11
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 17 | | let acc = mpu.get_acc_angles()?;
[INFO] [stdout]    | |           ^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:25:11
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 20 | | let acc = mpu.get_acc_angles_avg(Steps(5))?;
[INFO] [stdout]    | |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:28:12
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 23 | | let temp = mpu.get_temp()?;
[INFO] [stdout]    | |            ^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:31:12
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 26 | | let temp = mpu.get_temp_avg(Steps(5))?;
[INFO] [stdout]    | |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:34:12
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 29 | | let gyro = mpu.get_gyro()?;
[INFO] [stdout]    | |            ^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:37:12
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 32 | | let gyro = mpu.get_gyro_avg(Steps(5))?;
[INFO] [stdout]    | |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:40:11
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 35 | | let acc = mpu.get_acc()?;
[INFO] [stdout]    | |           ^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:43:11
[INFO] [stdout]    |
[INFO] [stdout] 2  | / fn main() {
[INFO] [stdout] 3  | | let i2c = I2cdev::new("/dev/i2c-1")
[INFO] [stdout] 4  | |     .map_err(Mpu6050Error::I2c)?;
[INFO] [stdout] 5  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 38 | | let acc = mpu.get_acc_avg(Steps(5))?;
[INFO] [stdout]    | |           ^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 39 | | }
[INFO] [stdout]    | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 22 previous errors
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0425, E0433.
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     src/lib.rs - (line 7)
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "4f734db7070352ac0b832562297ebc646901116f6e8b18a08940ba9d7d7cde76", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4f734db7070352ac0b832562297ebc646901116f6e8b18a08940ba9d7d7cde76", kill_on_drop: false }`
[INFO] [stdout] 4f734db7070352ac0b832562297ebc646901116f6e8b18a08940ba9d7d7cde76
