std::auto_ptr as exception object

{ Multi-posted article. -mod }

Hello,

I am using std::auto_ptr to try to keep ownership of resources
straight. However, I became aware that exception objects must provide
a copy constructor, which made me uncertain of the soundness of
throwing std::auto_ptrs...

It was explained to me that a problem is:

try {
   throw std::auto_ptr<int>(new int(10));
} catch (std::auto_ptr<int> a) {
   throw;
}

If I understood correctly, the re-throw would use the original
exception object, which has lost ownership.
Is there a way to prevent catching by value?
Is catching by reference kosher?
Are there other problems with throwing auto_ptrs?

Thanks.

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