* The buffer-pointer based init methods were passing the dispatch
data default destructor in such a way that the
@convention(block)-ness was lost. This leads to a thunk being passed
to dispatch instead of NULL. Subsequently, dispatch would reference
rather than copy the provided data.
Fixes:
SR-2050 (<rdar://problem/27293973>)
* Fix DispatchSourceSignal initialisation such that it no longer
registers for the wrong source type.
* Remove (group:) option from DispatchWorkItem, introduce group
options to `.async` methods that accept DispatchWorkItem.
* Rename `DispatchSourceType` to `DispatchSourceProtocol`
* Rework DispatchQueue attributes and flags into a less confusing
approach.
* Fixes:
SR-1817, SR-1771, SR-1770, SR-1769
<rdar://problem/26725156> <rdar://problem/26873917>
<rdar://problem/26918843> <rdar://problem/26810149>
<rdar://problem/27117023> <rdar://problem/27121422>
<rdar://problem/27236887> <rdar://problem/27337555>
Rather than managing API notes directly in the Clang importer, tell
Clang where to find the API notes files and let it map them directly
to attributes. Then, use the existing attribute-mapping
mechanisms---with minor extensions for cases where Clang previously
didn't map some Swift-specific API notes---to get at that information.
There is a minor regression where we can no longer apply API notes to
declarations that don't have a specific Clang declaration. The
specific example (NSError's inherited init()) comes from
rdar://problem/21042412; we've regressed here, but the correct fix is
(and has always been) on the Objective-C side
(rdar://problem/19977891).
Finishes rdar://problem/24447420.
