[WIP] Hashable: ~Copyable

[airspeedswift]

Based on #85079 but this last part is trapping in SILGen:

Assertion failed: (genericSig.getCanonicalSignature() == subs.getGenericSignature().getCanonicalSignature()), function emitApply, file SILGenApply.cpp, line 6099.
Please submit a bug report (https://swift.org/contributing/#reporting-bugs) and include the crash backtrace.
...
1.	Swift version 6.3-dev (LLVM 81388c1cc1c4050, Swift 510c0b87708fa62)
2.	Compiling with effective version 5.10
3.	While evaluating request ASTLoweringRequest(Lowering AST to SIL for module Swift)
4.	While silgen emitFunction SIL function "@$ss20_ArrayAnyHashableBoxVys0bC0VSicig".
 for getter for subscript(_:) (at /Users/ben/src/swift/swift/stdlib/public/core/Array.swift:2117:12)

[airspeedswift]

@swift-ci please smoke test macOS platform

[slavapestov]

That's an interesting assertion. Does a clean build not resolve it? Can you dump both generic signatures?

[slavapestov]

Oh, SILGen might have some magic for AnyHashable or keypaths that needs a minor fix for this.