2013/1/20 Ion Gaztañaga <igaztanaga@gmail.com>
El 19/01/2013 13:06, TONGARI escribió:
Hi there,
The code below would simply crash on g++ 4.7.1/MinGW with default
optimization level, it doesn't shown with -O/1/2/3
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boost::container::deque<int> d;
--d.begin();
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The problem is that decrementing a begin iterator is not a valid operator, since it would point out of the container.
But wouldn't it be a valid operation as long as we don't dereference from it?
I don't believe so.
If it was a pointer, then yes.
The closest I could find in the standard was section 24.2.6 (talking about bidirectional iterators), it says that a precondition for --r is:
there exists s such that r == ++s