There are a lot mismatches. For example, I reported a bug about CFRunLoopMode, where the original C-based CF used a comparison of pointer address to determine

There are a lot mismatches. For example, I reported a bug about CFRunLoopMode, where the original C-based CF used a comparison of pointer address to determine the equality of two run mode names. The original C version actually compared using the identity rather than equality as the commonModes was defined as a static CFStringRef (CONST_STRING_DECL(kCFRunLoopCommonModes, "kCFRunLoopCommonModes")). Of course this is an optimization for speed on Mac but this is, unfortunately, not supported in Swift and its replication of CF, because in Swift it has to be a public static String. As for today you cannot use commonModes in Linux.