test/Constraints/valid_pointer_conversions.swift

// RUN: %target-typecheck-verify-swift

func foo(_ a: [[UInt8]], _ p: [UnsafeRawPointer]) {
  foo(a, a) // expect-warning {{all paths through this function will call itself}}
}

// rdar://problem/44658089
func takesPtr(_: UnsafePointer<UInt8>) {}

func givesPtr(_ str: String) {
    takesPtr(UnsafePointer(str))
}