[5.1 08-28-2019] [Serialization] Teach serialization to get a generic signature from opaque types #27141
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Description: Fixes incorrect serialization of opaque return types for @inlinable code, and teaches serialization how to deserialize a generic signature from an opaque result type.
Scope of the issue: This prevents returning opaque result types from some @inlinable declarations when in incremental mode
Risk: Low, the patch ensures we start a cross-reference correctly regardless if the return type of a function is an opaque return type, and that we're able to deserialize it
Testing: Manually compiling projects using SwiftUI with @inlinable declarations and CI testing of reduced reproduction cases.
Reviewed-by: @jckarter
Radar: rdar://53958358