Non generic functions accept generic specialization syntax in some cases

[TeamPuzel]

Description

Swift is allowing a syntax mistake.

Reproduction

It seems that a function can "accept" explicit generic parameters in this situation:

func z() -> Int { 1 }                 // Non generic function
func z<T: FloatingPoint>() -> T { 1 } // Generic overload of that function
let y: Int = z<Float>()               // Nonsense syntax compiles (the parameter is ignored but there is no error)

It does not seem to happen when either of the overloads is commented out, catching the invalid syntax.

Expected behavior

An error message detecting the misleading syntax.

Environment

Apple Swift version 6.0-dev (LLVM 3417addab6ff197, Swift d677b7c23fd6355)
Target: arm64-apple-macosx14.0

Additional information

No response

[tbkka]

CC: @slavapestov @xedin

[xedin]

I think @gregomni fixed this recently via #75526

[xedin]

Main compiler produces:

3 | let y: Int = z<Float>()
  |              `- error: cannot specialize non-generic type '() -> Int'

[AnthonyLatsis]

Almost certainly. Bug still there in my June 4th checkout.

[AnthonyLatsis]

Duplicate of #74857