Use the portable spelling for the nullability keywords (_Nullable, _Nonnullable,
_Null_unspecified) rather than the old spelling (__nullable, __nonnullable,
__null_unspecified). NFC.
The general rule here is that something needs to be SWIFT_CC(swift)
if it's just declared in Swift code using _silgen_name, as opposed to
importing something via a header.
Of course, SWIFT_CC(swift) expands to nothing by default for now, and
I haven't made an effort yet to add the indirect-result / context
parameter ABI attributes. This is just a best-effort first pass.
I also took the opportunity to shift a few files to just implement
their shims header and to demote a few things to be private stdlib
interfaces.
This allows removal of the DebugDescription protocol which is invalid
because no classes actually conform to it. The problem is that we need
to send a debugDescription message to an NSObject without loading
Foundation. This is exactly what shims are for. A very simple shim
solves the problem.
The standard library has grown significantly, and we need a new
directory structure that clearly reflects the role of the APIs, and
allows future growth.
See stdlib/{public,internal,private}/README.txt for more information.
Swift SVN r25876
