`matches` is ambiguous

[Mark-Simulacrum]

I feel like we've seen this before, but filing since it looks like it's occurring again in 1.94.

https://crater-reports.s3.amazonaws.com/beta-1.94-3/beta-2026-01-26/gh/3scale-rs.threescale-wasm-auth/log.txt

[INFO] [stdout] error[E0659]: `matches` is ambiguous
[INFO] [stdout]   --> /opt/rustwide/cargo-home/git/checkouts/threescalers-3c034920aa4ddc80/f813a7a/src/api_call.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |         matches!(self, Kind::Report)
[INFO] [stdout]    |         ^^^^^^^ ambiguous name
[INFO] [stdout]    |
[INFO] [stdout]    = note: ambiguous because of a conflict between a `macro_rules` name and a non-`macro_rules` name from another module
[INFO] [stdout] note: `matches` could refer to the macro defined here
[INFO] [stdout]   --> /opt/rustwide/cargo-home/git/checkouts/threescalers-3c034920aa4ddc80/f813a7a/src/util/compat/macros.rs:3:1
[INFO] [stdout]    |
[INFO] [stdout]  3 | / macro_rules! matches {
[INFO] [stdout]  4 | |     ($expression:expr, $( $pattern:pat )|+ $( if $guard: expr )? $(,)?) => {
[INFO] [stdout]  5 | |         match $expression {
[INFO] [stdout]  6 | |             $( $pattern )|+ $( if $guard )? => true,
[INFO] [stdout] ...  |
[INFO] [stdout] 10 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] note: `matches` could also refer to the macro imported here
[INFO] [stdout]   --> /opt/rustwide/cargo-home/git/checkouts/threescalers-3c034920aa4ddc80/f813a7a/src/api_call.rs:1:5
[INFO] [stdout]    |
[INFO] [stdout]  1 | use std::prelude::v1::*;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    = help: use `self::matches` to refer to this macro unambiguously

Panic:

• https://crater-reports.s3.amazonaws.com/beta-1.94-3/beta-2026-01-26/gh/Joystream.runtime-example-module/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.94-3/beta-2026-01-26/gh/kRITZCREEK.siml/log.txt

[Mark-Simulacrum]

Possibly another case:

• https://crater-reports.s3.amazonaws.com/beta-1.94-3/beta-2026-01-26/reg/hebo-0.3.3/log.txt

[INFO] [stdout] error[E0659]: `sigset_t` is ambiguous
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/nc-0.8.13/src/platform/linux-types/fs/aio.rs:13:18
[INFO] [stdout]    |
[INFO] [stdout] 13 |     pub sigmask: sigset_t,
[INFO] [stdout]    |                  ^^^^^^^^ ambiguous name
[INFO] [stdout]    |
[INFO] [stdout]    = note: ambiguous because of multiple glob imports of a name in the same module
[INFO] [stdout] note: `sigset_t` could refer to the type alias imported here
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/nc-0.8.13/src/platform/linux-types/x86_64/mod.rs:15:9
[INFO] [stdout]    |
[INFO] [stdout] 15 | pub use uapi_signal::*;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^
[INFO] [stdout]    = help: consider adding an explicit import of `sigset_t` to disambiguate
[INFO] [stdout] note: `sigset_t` could also refer to the struct imported here
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/nc-0.8.13/src/platform/linux-types/x86_64/mod.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub use signal::*;
[INFO] [stdout]    |         ^^^^^^^^^
[INFO] [stdout]    = help: consider adding an explicit import of `sigset_t` to disambiguate

[Mark-Simulacrum]

• https://crater-reports.s3.amazonaws.com/beta-1.94-3/beta-2026-01-26/reg/polywrap_http_plugin-0.1.11/log.txt

[INFO] [stdout] warning: `Result` is ambiguous
[INFO] [stdout]    --> src/lib.rs:108:53
[INFO] [stdout]     |
[INFO] [stdout] 108 | fn handle_json(request: UreqRequest, body: &str) -> Result<UreqResponse, HttpPluginError> {
[INFO] [stdout]     |                                                     ^^^^^^ ambiguous name
[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 #114095 <https://github.com/rust-lang/rust/issues/114095>
[INFO] [stdout]     = note: ambiguous because of multiple glob imports of a name in the same module
[INFO] [stdout] note: `Result` could refer to the type alias defined here
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/polywrap_plugin-0.1.11/src/lib.rs:25:9
[INFO] [stdout]     |
[INFO] [stdout]  25 | pub use serde_json::*;
[INFO] [stdout]     |         ^^^^^^^^^^
[INFO] [stdout]     = help: consider updating this dependency to resolve this error
[INFO] [stdout]     = help: if updating the dependency does not resolve the problem report the problem to the author of the relevant crate
[INFO] [stdout] note: `Result` could also refer to the type alias defined here
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/polywrap_plugin-0.1.11/src/lib.rs:17:69
[INFO] [stdout]     |
[INFO] [stdout]  17 | pub use polywrap_msgpack_serde::{serde_bytes::ByteBuf, to_vec, Map, *};
[INFO] [stdout]     |                                                                     ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0107]: type alias takes 1 generic argument but 2 generic arguments were supplied
[INFO] [stdout]   --> src/wrap/module.rs:22:67
[INFO] [stdout]    |
[INFO] [stdout] 22 |   fn get(&mut self, args: &ArgsGet, invoker: Arc<dyn Invoker>) -> Result<Option<Response>, PluginError>;
[INFO] [stdout]    |                                                                   ^^^^^^                 ------------- help: remove the unnecessary generic argument
[INFO] [stdout]    |                                                                   |
[INFO] [stdout]    |                                                                   expected 1 generic argument
[INFO] [stdout]    |
[INFO] [stdout] note: type alias defined here, with 1 generic parameter: `T`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/serde_json-1.0.149/src/error.rs:25:10
[INFO] [stdout]    |
[INFO] [stdout] 25 | pub type Result<T> = result::Result<T, Error>;
[INFO] [stdout]    |          ^^^^^^ -

[eggyal]

Having some trouble bisecting gh/3scale-rs.threescale-wasm-auth and reg/hebo-0.3.3 (the former is doing some conditional compilation via autoconf, which results in different failures under the bisector; and the latter hits some interim failures when using a version of proc_macro2 that requires the since-removed proc_macro::LineColumn). I'll return to them a bit later.

The failures in gh/Joystream.runtime-example-module and gh/kRITZCREEK.siml bisect to 9b81629 (#139493).

The failure in reg/polywrap_http_plugin-0.1.11 bisects to c61a3a4 (#147984).

[apiraino]

For #139493 cc @Voultapher and @petrochenkov (unsure if in the end a breaking change was ruled out)

For #147984 instead we do have a relnotes label - so I assume it's expected

[Voultapher]

At least the threescalres one is a known and expected regression #139493 (comment).

I'll try to flesh out #150437

[apiraino]

Removing prioritization since these are expected breakages

@rustbot label -I-prioritize