stream iterators into different streams compare equal

• Key: STDCXX-645
• Type: Bug
• Status: Closed
• Resolution: Fixed
• Priority: Major
• Assignee: Martin Sebor
• Reporter: Mark Brown
• Component/s: 24. Iterators
• Affects Version/s: 4.1.3, 4.2.0
• Fix Version/s: 4.2.1

Description

As Travis says in his reply to my post here:
http://www.nabble.com/stream-iterators-into-different-streams-compare-equal--tf4721505.html#a13498487:

Given 24.5.1.1 p1 and p2, it is pretty clear to me that the two iterators are both non-end-of-stream type, and they are both created on different streams. The streams are different, so the iterators should not compare equal. I guess one could claim that 24.5.1.2 p6 conflicts with 24.5 p3 because 'end-of-stream' isn't clearly defined, but in this particular case that doesn't matter.

This program aborts with stdcxx but not with gcc:

#include <assert.h>
#include <iterator>
#include <sstream>

int main ()
{
    std::istringstream a ("1");
    std::istream_iterator<int> i (a);

    std::istringstream b ("2");
    std::istream_iterator<int> j (b);

    assert (!(i == j));
}