NSFastEnumeration doesn't warn about mismatched types when using Objective-C generics

Originator:heath.borders
Number:rdar://25060476 Date Originated:09-Mar-2016 10:38 AM
Status:Open Resolved:
Product:Developer Tools Product Version:Version 7.2 (7C68)
Classification:Serious Bug Reproducible:Always
 
Summary:
Using NSFastEnumeration with for..in syntax does not warn on generic type mismatches.

Steps to Reproduce:
Compile the following code:
    NSArray<NSString *> *strings = @[@"1",
                         ];
    for (NSNumber *number in strings) {
        NSLog(@"number: %@",
              number);
    }
    
    NSDictionary<NSString *, NSString *> *stringsByString = @{@"1" : @"1",
                                                              };
    for (NSNumber *number in stringsByString) {
        NSLog(@"number: %@",
              number);
    }

Expected Results:
The compiler should emit warnings about both for loops because their types don’t match the generic type of the container.

Actual Results:
The compile emits no warnings.

Regression:


Notes:

Comments


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