1.1.8.9. osx.cocoa.IncompatibleMethodTypes (ObjC)
Warn about Objective-C method signatures with type incompatibilities.

Examples:

@interface MyClass1 : NSObject
- (int)foo;
@end

@implementation MyClass1
- (int)foo { return 1; }
@end

@interface MyClass2 : MyClass1
- (float)foo;
@end

@implementation MyClass2
- (float)foo { return 1.0; } // warn
@end