Re: problem: returned iterator is valid but the std:list is empty

"Doug Harrison [MVP]" <>
Fri, 09 Jun 2006 14:04:44 -0500
On Fri, 9 Jun 2006 09:56:01 -0700, Jaime Stuardo
<> wrote:

Hi all...

I have a strange problem...

I have this code in a destructor :

for( std::list<COraDatabase *>::iterator it = m_listDB.begin(); it !=
m_listDB.end(); it++ )
            delete (*it);

Where m_listDB is of std::list<COraDatabase *> type. Before the "for",
m_listDB.size( ) returns 0. When I debug the "for", m_listDB.begin( ) retuns
an iterator that is different from m_lisDB.end( ), so execution continues
inside the "for". Of course, application crashes, because (*it) is undefined.

Do you know what is happening here? what else can I test in order to find
the explanation and the solution?

VC's std::list maintains its size as a member variable (providing O(1) size
determination which is _not_ guaranteed), so I'd say you have corrupted
your std::list object at some point, or you've somehow triggered a bug in
the compiler. What do you expect the list size to be at this point?

Doug Harrison
Visual C++ MVP

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