Pointer initialization in class initialization

Question

Given

class Foo {
    public:
        bool *b;
        Foo();
};
Foo::Foo()
    :b()
{      
}

int main()
{
    Foo foo;
}

What does the b() do in the class initializer list? It seems to maybe initialize the pointer's value to 0.

songyuanyao · Accepted Answer · 2019-07-10 04:36:04Z

3

This is value initialization; as the effect, built-in types will be zero-initialized. That means b will be initialized to 0 (the null pointer).

4) otherwise, the object is zero-initialized.

and

If T is a scalar type, the object's initial value is the integral constant zero explicitly converted to T.

and also

Zero- and value-initialization also initialize pointers to their null values.

answered Jul 10, 2019 at 4:26

songyuanyao

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