Add the `RE2_BUILD_FRAMEWORK` option to build RE2 as a framework.

See for details.
This has no effect unless RE2 is being built for an Apple platform
such as macOS or iOS.

Credit and gratitude to Yi Wang for proposing and explaining this.

Change-Id: I881e5707fd43cbfcef04e048ca68bcb6da9846ed
Reviewed-by: Alex Chernyakhovsky <>
Reviewed-by: Paul Wankadia <>
1 file changed