Pick D42933 back up, and make NSInteger/NSUInteger with %zu/%zi specifiers on Darwin warn only in pedantic mode. The default -Wformat recently started warning for the following code because of the added support for analysis for the '%zi' specifier.
NSInteger i = NSIntegerMax; NSLog(@"max NSInteger = %zi", i);
The problem is that on armv7 %zi is 'long', and NSInteger is typedefed to 'int' in Foundation. We should avoid this warning as it's inconvenient to our users: it's target specific (happens only on armv7 and not arm64), and breaks their existing code. We should also silence the warning for the '%zu' specifier to ensure consistency. This is acceptable because Darwin guarantees that, despite the unfortunate choice of typedef, sizeof(size_t) == sizeof(NS[U]Integer), the warning is therefore noisy for pedantic reasons. Once this is in I'll update public documentation.
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