[INFO] fetching crate try_v2 0.11.1...
[INFO] testing try_v2-0.11.1 against 1.99.0-beta.8+cargoflags=--release for beta-release-1.100-2
[INFO] extracting crate try_v2 0.11.1 into /workspace/builds/worker-2-tc1/source
[INFO] started tweaking crates.io crate try_v2 0.11.1
[INFO] removed 0 missing examples
[INFO] finished tweaking crates.io crate try_v2 0.11.1
[INFO] tweaked toml for crates.io crate try_v2 0.11.1 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate try_v2 0.11.1 on toolchain 1.99.0-beta.8
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.99.0-beta.8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate try_v2 0.11.1 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" "+1.99.0-beta.8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded try_v2_derive v0.11.1
[INFO] [stderr]   Downloaded try_v2_traits v0.11.1
[INFO] [stderr]   Downloaded proc_macro2_diagnostic v0.8.1
[INFO] [stderr]   Downloaded build_safely v0.6.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:77db811e55d90add9212f6832c23229e3de5f1c1f9905e8cb07319ea15df73ac" "sleep" "infinity", kill_on_drop: false }`
[INFO] [stdout] f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062
[INFO] running `Command { std: "docker" "start" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062" "/opt/rustwide/cargo-home/bin/cargo" "+1.99.0-beta.8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062" "/opt/rustwide/cargo-home/bin/cargo" "+1.99.0-beta.8" "build" "--frozen" "--message-format=json" "--release", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v2.0.119
[INFO] [stderr]    Compiling syn v3.0.9
[INFO] [stderr]    Compiling strum_macros v0.28.0
[INFO] [stderr]    Compiling strum v0.28.0
[INFO] [stderr]    Compiling build_safely v0.6.1
[INFO] [stderr]    Compiling try_v2_traits v0.11.1
[INFO] [stderr]    Compiling proc_macro2_diagnostic v0.8.1
[INFO] [stderr]    Compiling try_v2_derive v0.11.1
[INFO] [stderr]    Compiling try_v2 v0.11.1 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `release` profile [optimized] target(s) in 6.23s
[INFO] running `Command { std: "docker" "inspect" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062" "/opt/rustwide/cargo-home/bin/cargo" "+1.99.0-beta.8" "test" "--frozen" "--no-run" "--message-format=json" "--release", kill_on_drop: false }`
[INFO] [stderr]    Compiling try_v2 v0.11.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/BangMatching.rs:12:25
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let x: ValidatedBox<!> = InvalidValue;
[INFO] [stdout]    |                         ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0658`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `try_v2` (example "BangMatching") due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/Transpose.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(try_trait_v2)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/signatures.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(try_trait_v2)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `try_v2::Try`
[INFO] [stdout]  --> examples/basic.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use try_v2::Try;
[INFO] [stdout]   |     ^^^^^^^^---
[INFO] [stdout]   |             |
[INFO] [stdout]   |             no `Try` in the root
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/doubleQ.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(try_trait_v2)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/doubleQ.rs:39:25
[INFO] [stdout]    |
[INFO] [stdout] 39 |     type Residual = Foo<!>;
[INFO] [stdout]    |                         ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/doubleQ.rs:50:26
[INFO] [stdout]    |
[INFO] [stdout] 50 | impl<T> FromResidual<Foo<!>> for Foo<T> {
[INFO] [stdout]    |                          ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/doubleQ.rs:53:44
[INFO] [stdout]    |
[INFO] [stdout] 53 |     default fn from_residual(residual: Foo<!>) -> Self {
[INFO] [stdout]    |                                            ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/doubleQ.rs:58:29
[INFO] [stdout]    |
[INFO] [stdout] 58 | impl<T> Residual<T> for Foo<!> {
[INFO] [stdout]    |                             ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `try_v2` (example "Transpose") due to 1 previous error
[INFO] [stderr] error: could not compile `try_v2` (example "basic") due to 1 previous error
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/clear_ready.rs:40:83
[INFO] [stdout]    |
[INFO] [stdout] 40 |     fn clear_ready(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<!>>;
[INFO] [stdout]    |                                                                                   ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/clear_ready.rs:54:83
[INFO] [stdout]    |
[INFO] [stdout] 54 |     fn clear_ready(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<!>> {
[INFO] [stdout]    |                                                                                   ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `try_v2` (example "signatures") due to 1 previous error
[INFO] [stderr] error: could not compile `try_v2` (example "doubleQ") due to 5 previous errors
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/chaining.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(try_trait_v2)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/Unwrap.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(try_trait_v2)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `try_v2_derive::Try`
[INFO] [stdout]  --> examples/Nested_Try.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use try_v2_derive::Try;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^---
[INFO] [stdout]   |                    |
[INFO] [stdout]   |                    no `Try` in the root
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this trait instead
[INFO] [stdout]   |
[INFO] [stdout] 8 - use try_v2_derive::Try;
[INFO] [stdout] 8 + use std::ops::Try;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/Nested_Try.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(try_trait_v2)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be applied to values that implement `Try`
[INFO] [stdout]   --> examples/Nested_Try.rs:24:19
[INFO] [stdout]    |
[INFO] [stdout] 24 |         let baz = foo? + 1;
[INFO] [stdout]    |                   ^^^^ the `?` operator cannot be applied to type `DuplicateData<i32>`
[INFO] [stdout]    |
[INFO] [stdout] help: the nightly-only, unstable trait `Try` is not implemented for `DuplicateData<i32>`
[INFO] [stdout]   --> examples/Nested_Try.rs:14:1
[INFO] [stdout]    |
[INFO] [stdout] 14 | enum DuplicateData<T> {
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^
[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]   --> examples/Nested_Try.rs:24:22
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn process(foo: DuplicateData<i32>) -> DuplicateData<i32> {
[INFO] [stdout]    |     --------------------------------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] 24 |         let baz = foo? + 1;
[INFO] [stdout]    |                      ^ cannot use the `?` operator in a function that returns `DuplicateData<i32>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `try_v2` (example "chaining") due to 1 previous error
[INFO] [stdout] error[E0432]: unresolved import `try_v2_derive::Try`
[INFO] [stdout]  --> examples/TryFrom2.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use try_v2_derive::Try;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^---
[INFO] [stdout]   |                    |
[INFO] [stdout]   |                    no `Try` in the root
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this trait instead
[INFO] [stdout]   |
[INFO] [stdout] 6 - use try_v2_derive::Try;
[INFO] [stdout] 6 + use std::ops::Try;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `try_v2` (example "Unwrap") due to 1 previous error
[INFO] [stdout] For more information about this error, try `rustc --explain E0658`.
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0432, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `FromResidual` in this scope
[INFO] [stdout]   --> examples/TryFrom2.rs:20:3
[INFO] [stdout]    |
[INFO] [stdout] 20 | #[FromResidual(Result<_, Self::Residual>)]
[INFO] [stdout]    |   ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `try_v2` (example "clear_ready") due to 2 previous errors
[INFO] [stderr] error: could not compile `try_v2` (example "Nested_Try") due to 4 previous errors
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/TryFrom2.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(try_trait_v2)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/TryFrom2.rs:11:18
[INFO] [stdout]    |
[INFO] [stdout] 11 |     type Error = !;
[INFO] [stdout]    |                  ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/TryFrom2.rs:48:28
[INFO] [stdout]    |
[INFO] [stdout] 48 |     type Error = Eightball<!, Odd>;
[INFO] [stdout]    |                            ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: the `!` type is experimental
[INFO] [stdout]   --> examples/TryFrom2.rs:50:54
[INFO] [stdout]    |
[INFO] [stdout] 50 |     fn try_from(num: i32) -> Result<Even2, Eightball<!, Odd>> {
[INFO] [stdout]    |                                                      ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #35121 <https://github.com/rust-lang/rust/issues/35121> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the trait bound `Eightball<Even, Odd>: Try` is not satisfied
[INFO] [stdout]   --> examples/TryFrom2.rs:33:19
[INFO] [stdout]    |
[INFO] [stdout] 33 |     type Return = Eightball<Self, Odd>;
[INFO] [stdout]    |                   ^^^^^^^^^^^^^^^^^^^^ unsatisfied trait bound
[INFO] [stdout]    |
[INFO] [stdout] help: the nightly-only, unstable trait `Try` is not implemented for `Eightball<Even, Odd>`
[INFO] [stdout]   --> examples/TryFrom2.rs:22:1
[INFO] [stdout]    |
[INFO] [stdout] 22 | enum Eightball<Y, N> {
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `try_v2_derive::Try`
[INFO] [stdout]  --> examples/TraitExt_Try.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use try_v2_derive::Try;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^---
[INFO] [stdout]   |                    |
[INFO] [stdout]   |                    no `Try` in the root
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this trait instead
[INFO] [stdout]   |
[INFO] [stdout] 9 - use try_v2_derive::Try;
[INFO] [stdout] 9 + use std::ops::Try;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/TraitExt_Try.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(try_trait_v2)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be applied to values that implement `Try`
[INFO] [stdout]   --> examples/TryFrom2.rs:77:13
[INFO] [stdout]    |
[INFO] [stdout] 77 |     let n = <Even as TryFrom<i32>>::try_from(num)?;
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the `?` operator cannot be applied to type `Eightball<Even, Odd>`
[INFO] [stdout]    |
[INFO] [stdout] help: the nightly-only, unstable trait `Try` is not implemented for `Eightball<Even, Odd>`
[INFO] [stdout]   --> examples/TryFrom2.rs:22:1
[INFO] [stdout]    |
[INFO] [stdout] 22 | enum Eightball<Y, N> {
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^
[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]   --> examples/TryFrom2.rs:77:50
[INFO] [stdout]    |
[INFO] [stdout] 76 | fn even_string_own_try_type(num: i32) -> Eightball<String, Odd> {
[INFO] [stdout]    | --------------------------------------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] 77 |     let n = <Even as TryFrom<i32>>::try_from(num)?;
[INFO] [stdout]    |                                                  ^ cannot use the `?` operator in a function that returns `Eightball<String, Odd>`
[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]   --> examples/TryFrom2.rs:85:51
[INFO] [stdout]    |
[INFO] [stdout] 84 | fn even_string_via_result(num: i32) -> Eightball<String, Odd> {
[INFO] [stdout]    | ------------------------------------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] 85 |     let n = <Even2 as TryFrom<i32>>::try_from(num)?;
[INFO] [stdout]    |                                                   ^ cannot use the `?` operator in a function that returns `Eightball<String, Odd>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be applied to values that implement `Try`
[INFO] [stdout]   --> examples/TraitExt_Try.rs:38:17
[INFO] [stdout]    |
[INFO] [stdout] 38 |         let n = self? + rhs;
[INFO] [stdout]    |                 ^^^^^ the `?` operator cannot be applied to type `Counter<N>`
[INFO] [stdout]    |
[INFO] [stdout] help: the nightly-only, unstable trait `Try` is not implemented for `Counter<N>`
[INFO] [stdout]   --> examples/TraitExt_Try.rs:15:1
[INFO] [stdout]    |
[INFO] [stdout] 15 | enum Counter<N> {
[INFO] [stdout]    | ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a method that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> examples/TraitExt_Try.rs:38:21
[INFO] [stdout]    |
[INFO] [stdout] 36 |     fn add(self, rhs: M) -> Self::Output {
[INFO] [stdout]    |     ------------------------------------ this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] 37 |         info!("adding {rhs} to counter");
[INFO] [stdout] 38 |         let n = self? + rhs;
[INFO] [stdout]    |                     ^ cannot use the `?` operator in a method that returns `Counter<N>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0432, E0554, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0432, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `try_v2` (example "TryFrom2") due to 10 previous errors
[INFO] [stderr] error: could not compile `try_v2` (example "TraitExt_Try") due to 4 previous errors
[INFO] running `Command { std: "docker" "inspect" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062", kill_on_drop: false }`
[INFO] [stdout] f329e8eba69a3e70721ef09c6ea071efc1300a319991a472b53b2c7ef5dd2062
