[INFO] fetching crate winmix 0.1.3...
[INFO] testing winmix-0.1.3 against 1.90.0 for beta-1.91-3
[INFO] extracting crate winmix 0.1.3 into /workspace/builds/worker-4-tc1/source
[INFO] started tweaking crates.io crate winmix 0.1.3
[INFO] finished tweaking crates.io crate winmix 0.1.3
[INFO] tweaked toml for crates.io crate winmix 0.1.3 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate winmix 0.1.3 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate winmix 0.1.3 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" "+1.90.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded windows-interface v0.56.0
[INFO] [stderr]   Downloaded windows-implement v0.56.0
[INFO] [stderr]   Downloaded windows-core v0.56.0
[INFO] [stderr]   Downloaded windows-result v0.1.1
[INFO] [stderr]   Downloaded proc-macro2 v1.0.81
[INFO] [stderr]   Downloaded syn v2.0.60
[INFO] [stderr]   Downloaded windows v0.56.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bceed56425c2803f28647ac9cfe46c1924bc39001e993d814356325be2f34a6b
[INFO] running `Command { std: "docker" "start" "-a" "bceed56425c2803f28647ac9cfe46c1924bc39001e993d814356325be2f34a6b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bceed56425c2803f28647ac9cfe46c1924bc39001e993d814356325be2f34a6b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bceed56425c2803f28647ac9cfe46c1924bc39001e993d814356325be2f34a6b", kill_on_drop: false }`
[INFO] [stdout] bceed56425c2803f28647ac9cfe46c1924bc39001e993d814356325be2f34a6b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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=warn" "-e" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f17edb9740dbe0563c474c5392d4eb7d022d740452b6e80f400b256b4dd4ce6a
[INFO] running `Command { std: "docker" "start" "-a" "f17edb9740dbe0563c474c5392d4eb7d022d740452b6e80f400b256b4dd4ce6a", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.81
[INFO] [stderr]    Compiling unicode-ident v1.0.12
[INFO] [stderr]    Compiling windows_x86_64_gnu v0.52.5
[INFO] [stderr]    Compiling windows-targets v0.52.5
[INFO] [stderr]    Compiling windows-result v0.1.1
[INFO] [stderr]    Compiling quote v1.0.36
[INFO] [stderr]    Compiling syn v2.0.60
[INFO] [stderr]    Compiling windows-interface v0.56.0
[INFO] [stderr]    Compiling windows-implement v0.56.0
[INFO] [stderr]    Compiling windows-core v0.56.0
[INFO] [stderr]    Compiling windows v0.56.0
[INFO] [stderr]    Compiling winmix v0.1.3 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 10.42s
[INFO] running `Command { std: "docker" "inspect" "f17edb9740dbe0563c474c5392d4eb7d022d740452b6e80f400b256b4dd4ce6a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f17edb9740dbe0563c474c5392d4eb7d022d740452b6e80f400b256b4dd4ce6a", kill_on_drop: false }`
[INFO] [stdout] f17edb9740dbe0563c474c5392d4eb7d022d740452b6e80f400b256b4dd4ce6a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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=warn" "-e" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 317d5beec49a9b4c687a0acdfe8bc00f129874d19755afef805682cceeb0ebe5
[INFO] running `Command { std: "docker" "start" "-a" "317d5beec49a9b4c687a0acdfe8bc00f129874d19755afef805682cceeb0ebe5", kill_on_drop: false }`
[INFO] [stderr]    Compiling winmix v0.1.3 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.74s
[INFO] running `Command { std: "docker" "inspect" "317d5beec49a9b4c687a0acdfe8bc00f129874d19755afef805682cceeb0ebe5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "317d5beec49a9b4c687a0acdfe8bc00f129874d19755afef805682cceeb0ebe5", kill_on_drop: false }`
[INFO] [stdout] 317d5beec49a9b4c687a0acdfe8bc00f129874d19755afef805682cceeb0ebe5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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=warn" "-e" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] b6a41addeb985e009a9350fd905f074fcc3c7be9f6383a1933096a9ac075a29d
[INFO] running `Command { std: "docker" "start" "-a" "b6a41addeb985e009a9350fd905f074fcc3c7be9f6383a1933096a9ac075a29d", kill_on_drop: false }`
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/winmix-8c7fa8a9a0735c8d)
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests winmix
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test src/lib.rs - (line 11) - compile ... FAILED
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- src/lib.rs - (line 11) stdout ----
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:19:38
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 11 |     let sessions = winmix.enumerate()?;
[INFO] [stdout]    |                                      ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() -> Result<(), Box<dyn std::error::Error>> {
[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 `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:26:35
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 18 |         session.vol.set_mute(true)?;
[INFO] [stdout]    |                                   ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() -> Result<(), Box<dyn std::error::Error>> {
[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 `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:27:36
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 19 |         session.vol.set_mute(false)?;
[INFO] [stdout]    |                                    ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() -> Result<(), Box<dyn std::error::Error>> {
[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 `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:30:43
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 22 |         session.vol.set_master_volume(0.5)?;
[INFO] [stdout]    |                                           ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() -> Result<(), Box<dyn std::error::Error>> {
[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 `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:32:43
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 24 |         session.vol.set_master_volume(1.0)?;
[INFO] [stdout]    |                                           ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() -> Result<(), Box<dyn std::error::Error>> {
[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 `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:35:50
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 27 |         let vol = session.vol.get_master_volume()?;
[INFO] [stdout]    |                                                  ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() -> Result<(), Box<dyn std::error::Error>> {
[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 `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:36:46
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 28 |         let is_muted = session.vol.get_mute()?;
[INFO] [stdout]    |                                              ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout]  4 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_11_0() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout]    |                                                                         +++++++++++++++++++++++++++++++++++++++++
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 7 previous errors
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     src/lib.rs - (line 11)
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.11s
[INFO] [stdout] 
[INFO] [stderr] error: doctest failed, to rerun pass `--doc`
[INFO] running `Command { std: "docker" "inspect" "b6a41addeb985e009a9350fd905f074fcc3c7be9f6383a1933096a9ac075a29d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b6a41addeb985e009a9350fd905f074fcc3c7be9f6383a1933096a9ac075a29d", kill_on_drop: false }`
[INFO] [stdout] b6a41addeb985e009a9350fd905f074fcc3c7be9f6383a1933096a9ac075a29d
