1 // CS4025: The CallerFilePath applied to parameter `x' will have no effect because it applies to a member that is used in context that do not allow optional arguments
3 // Compiler options: -warnaserror
5 using System
.Runtime
.CompilerServices
;
9 partial void Foo (string x
= "x");
14 partial void Foo ([CallerFilePath
] string x
)