iOS 15 crash with objc_getClass

I’ll need more details to offer any advice here. Let’s start with the basics: Please post an Apple crash report of the problem, per the advice in Posting a Crash Report.

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The text version of the crash report should be attached. There are two relevant snippets of code for this crash to happen:

@available(iOS 16.0, *)
@MainActor
final class ScanViewModel {

    var scanTextType: DataScannerViewController.TextContentType?

    @Published var recognizedItems: [RecognizedItem] = []
}

In this block, we use the @available annotation to try and stop things that don't exist in iOS 15 from being accessed. Later, in instrumentation:

    unsigned int classNameCount = 0;
    const char **classNames = objc_copyClassNamesForImage(mainImageName, &classNameCount);
    for (NSUInteger i = 0; i < classNameCount; i++) {
        Class cls = objc_getClass(classNames[i]);
        NRMA__processClass(cls, results, parents);
    }
    free(classNames);

This crashes on the call to objc_getClass() when passed the class which has the @available annotation.

What I am asking is if there is a workaround for this bug in iOS 15 (this doesn't happen on iOS 16 and above)? Thank you.

Hi. Is there a more convenient workaround, or something that can perhaps be done when calling objc_getClass to avoid this crash, or am I doomed to have to annotate every aspect of the class until iOS 15 goes out of style?