some cannot be used instead of a generic placeholder for never-returned type inference

[JessyCatterwaul]

Description

some Any works for most replacements of generic placeholders that only get used one time. But it doesn't work with whatever type inference errors use.

Reproduction

Compiles:

extension Error {
  func `throw`<Never>() throws -> Never {
    throw self
  }
}

Function declares an opaque return type, but has no return statements in its body from which to infer an underlying type :

extension Error {
  func `throw`() throws -> some Any {
    throw self
  }
}

---

The throw function is very useful. I haven't had a use for similar, when it comes to Never returns, but the same problem occurs there:

✅:

func never<Never>() -> Never { 
  fatalError()
}

❌:

func never() -> some Any {
  fatalError()
}

Expected behavior

The versions using some Any compile.

Environment

swift-driver version: 1.90.11.1 Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4)
Target: arm64-apple-macosx14.0

Additional information

No response