Why does std::cout convert volatile pointers to bool?

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ostream::operator<< has the following overloads, among others:

ostream& operator<< (bool val );
ostream& operator<< (const void* val );

When you pass in a volatile pointer, the second overload can’t apply because volatile pointers cannot be converted to non-volatile without an explicit cast. However, any pointer can be converted to bool, so the first overload is chosen, and the result you see is 1 or 0.

So the real reason for this is not an intentional decision on behalf of the standards committe, but simply that the standard does not specify an overload that takes a volatile pointer.

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