Is there an Objective-C equivalent to Swift's fatalError?

You can raise an exception in this case. Something like this:

[NSException raise:@"InitNotImplemented" format:@"Subclasses must implement a valid init method"];

NSAssert(NO, @"balabala");

- (instancetype)init NS_UNAVAILABLE;

========== Update ==========

Thanks to @Cœur

NSAssert is disabled by default in production, which is different with FatalError. NSException is better.

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Just call NSObject's doesNotRecognizeSelector: method. You would write:

- (instancetype) init
{
    [self doesNotRecognizeSelector:_cmd];
}

where _cmd is the hidden parameter to every method whose value is the selector of the method.

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