[STDCXX-769] __rw_debug_iter iterators are partially invalidated after swap() operation

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Won't Fix
• Affects Version/s: 4.1.2, 4.1.3, 4.1.4, 4.2.0
• Component/s: 24. Iterators

Environment

All

• Severity: Runtime Error
• Assignee: Unassigned
• Reporter: Farid Zaripov
• Created: 16/Mar/08 05:37
• Updated: 16/Mar/08 23:29
• Resolved: 16/Mar/08 05:42

Description

The __rw_debug_iter class contains pointer to associated container. After swap() operation the __rw_debug_iter iterators, obtained from container method (i.e. begin()) are associated with another container variable. Due to this any operation between iterators, obtained before swap and after swap will fail on assert (except operator==(), maybe some others).

The testcase:

test.cpp

#include <vector>
#include <cassert>

int main ()
{
    typedef std::vector<int> Vector;
    typedef Vector::iterator Iter;

    Vector v1, v2;
    v1.push_back (1);

    Iter v1_begin = v1.begin ();

    v1.swap (v2);

    assert (v1_begin == v2.begin ());
    assert (0 == v1_begin - v2.begin ());

    return 0;
};

The testcase result:

rw/_iterbase.h:527: int __thiscall __rw::__rw_debug_iter<class std::vector<int,class std::allocator<int> >,int *,int *>::operator -<int*>(const class __rw::__rw_debug_iter<class std::vector<int,class std::allocator<int> >,int *,int *> &) const: Assertion '_C_cont && _C_cont == __rhs._C_cont' failed.

This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.

Issue Links

• is related to: STDCXX-635 std::deque::swap invalidates begin() and end() iterators on empty container