Weird const-ness troubles

From: James Aguilar (jfa1_at_cec.wustl.edu)
Date: 03/03/05 

Date: Thu, 3 Mar 2005 02:26:00 -0600

Take the following code example:

class Array {
 double *m_array;
public:
 Array() { m_array = new double[10]; }
 double *begin() const {return m_array;}
};

int main() {
 const Array a = Array();
 double *iShouldNotExist(a.begin());
 iShouldNotExist[0] = -1000;
 return 0;
}

This code compiles and runs on g++ 3.3.3 with -pedantic and -ansi set. As I
see it, this code allows me to take an object declared as const and mess
around with its private internals because of a method call that promises
that the object will not be changed. What's up with that? I know that the
right way is to return a const double *, but shouldn't this kind of thing be
disallowed?

- JFA1

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