C ++: pointers and scope

Question

int* test( )
{
    int a = 5;
    int* b = &a;
    return b;
}

Will the result testbe a bad pointer? As far as I know, a should be deleted and then bbecome a confused pointer, right?

What about more complex things, not an int pointer, but the same with a class with 20 members or so?

Answer 1

The term for what you return is a dangling pointer . " aIs a local variable allocated on the stack and it is no longer available when it leaves the scope (which is no different from garbage collection). Attempting to use the result of the call test()will be undefined .

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Answer 2

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int test( )
{
    int a = 5;
    return a;
}

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Answer 3

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Answer 4

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