Rollup merge of #121382 - nnethercote:rework-untranslatable_diagnostic-lint, r=davidtwco

Rework `untranslatable_diagnostic` lint

Currently it only checks calls to functions marked with `#[rustc_lint_diagnostics]`. This PR changes it to check calls to any function with an `impl Into<{D,Subd}iagnosticMessage>` parameter. This greatly improves its coverage and doesn't rely on people remembering to add `#[rustc_lint_diagnostics]`. It also lets us add `#[rustc_lint_diagnostics]` to a number of functions that don't have an `impl Into<{D,Subd}iagnosticMessage>`, such as `Diag::span`.

r? ``@davidtwco``

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/rustc_feature/src/builtin_attrs.rs b/compiler/rustc_feature/src/builtin_attrs.rs
index 3f971aad042..0d51e1e46e0 100644
--- a/compiler/rustc_feature/src/builtin_attrs.rs
+++ b/compiler/rustc_feature/src/builtin_attrs.rs
@@ -695,8 +695,8 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     // Used by the `rustc::potential_query_instability` lint to warn methods which
     // might not be stable during incremental compilation.
     rustc_attr!(rustc_lint_query_instability, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE),
-    // Used by the `rustc::untranslatable_diagnostic` and `rustc::diagnostic_outside_of_impl` lints
-    // to assist in changes to diagnostic APIs.
+    // Used by the `rustc::diagnostic_outside_of_impl` lints to assist in changes to diagnostic
+    // APIs. Any function with this attribute will be checked by that lint.
     rustc_attr!(rustc_lint_diagnostics, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE),
     // Used by the `rustc::bad_opt_access` lint to identify `DebuggingOptions` and `CodegenOptions`
     // types (as well as any others in future).