Skip to content

[cxx-interop] Add documentation about inferring SWIFT_SHARED_REFERENCE in c++ inheritance #1078

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 4 commits into from
Closed

[cxx-interop] Add documentation about inferring SWIFT_SHARED_REFERENCE in c++ inheritance #1078

Changes from 2 commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
0548af8
[cxx-interop] Add documentation about inferring SWIFT_SHARED_REFERENC…
fahadnayyar Jun 10, 2025
5115e68
Removed Swift class types from the text
fahadnayyar Jul 1, 2025
dd4d780
edits
fahadnayyar Jul 4, 2025
66da0bf
added some more info
fahadnayyar Jul 4, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 4 additions & 0 deletions documentation/cxx-interop/index.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1255,6 +1255,10 @@ object.doSomething()
// `object` will be released here.
```

### Inference for Derived Types

Swift compiler automatically infers the ```SWIFT_SHARED_REFERENCE``` annotation for C++ types that inherit from a base type annotated with ```SWIFT_SHARED_REFERENCE```. These derived types are also imported as a reference type in Swift that use the same ```retain``` and ```release``` functions as the base type. No additional annotation is required on the derived types.

Copy link
Contributor Author

@fahadnayyar fahadnayyar Jul 4, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@j-hui I changed some text based on your suggestions but added my flavor as well. How does it look now?

### Inheritance and Virtual Member Functions

Similar to value types, casting an instance of a derived reference type to a
Expand Down