swift

7b46d418 - [DebugInfo] Fix infinite recursion when opaque return type is defined

[DebugInfo] Fix infinite recursion when opaque return type is defined inside function returning it A stack overflow would happen when the compiler tried emitting debug info for a function whose opaque return type was declared inside the function itself. This fixes the issue by emitting a forward declaration for the function before emitting it. rdar://150313956 (cherry picked from commit c03831f70da3d67f7a024658595e47667e1f63ea)