 }
 
 CStringTests.test("String.decodeCString.with.String.input") {
+  guard #available(SwiftStdlib 5.7, *) else { return }
   let (u8p, dealloc) = getASCIIUTF8()
   defer { dealloc() }
   var result = String.decodeCString(

}

CStringTests.test("String.decodeCString.with.Array.input") {
  do {
    let (u8p, dealloc) = getASCIIUTF8()
    defer { dealloc() }

}

CStringTests.test("String.decodeCString.with.inout.conversion") {
  guard #available(SwiftStdlib 5.7, *) else { return }
  var c = Unicode.UTF8.CodeUnit.zero
  var result = String.decodeCString(
    &c, as: Unicode.UTF8.self, repairingInvalidCodeUnits: true
