/* * Copyright (c) 2014 - Facebook. * All rights reserved. */ #import @interface Fraction : NSObject { int numerator; int denominator; } - (void)setNumerator:(int)n; - (void)setDenominator:(int)d; - (int)getNumerator; - (int)getDenominator; @end @implementation Fraction - (void)setNumerator:(int)n { numerator = n; } - (void)setDenominator:(int)d { denominator = d; } - (int)getNumerator { return numerator; } - (int)getDenominator { return denominator; } @end Fraction *Fraction_create() { Fraction *f = NULL; return f; } int null_deref_objc_class() { Fraction *fraction = Fraction_create(); [fraction setNumerator: 5]; return 0; } void test_virtual_call() { id *fraction = [Fraction alloc]; // virtual call: the type of fraction is obtained from the allocation [fraction setNumerator: 5]; if ([fraction getNumerator] != 4) { // unreachable int *x = NULL; *x = 0; } [fraction release]; }