FreeTDS Development Group

["ZIGLIO, Frediano, VF-IT" <Frediano.Ziglio AT vodafone.com>]

> 
> "ZIGLIO, Frediano, VF-IT" <Frediano.Ziglio AT vodafone.com> wrote:
> > "Assertion `result_found || tds->current_results == ((void 
> *)0)' failed"
> > means that current_results do not point to any known data. 
> From gdb you
> > can see that current_results point to a buffer however we 
> can find this
> > buffer in res_info, param_info, compute, cursors or 
> dynamic... I always
> > though that current_results should point to one of these members...
> > valgrind prove that there is no memory leaks however I 
> don't understand
> > how this can happen....
> 
> Couldn't that be:
>       
>       result_found || tds->current_results == NULL
> 
> just as well?  That should be legal C everywhere.  
> 

Well this in my environment (Linux FC2) it's expanded to 
"result_found || tds->current_results == ((void *)0)"

> You don't need a memory leak for this to happen.  If you free 
> the memory,
> and don't set the pointer to NULL, the assertion will fail.  
> Maybe if we
> used TDS_ZERO_FREE more consistently, that wouldn't happen.  
> (Not that I
> do, but still.)
> 

In this case tds->current_results points but not own the pointer (it's
an alias) so freeing it it's wrong. It was a pointer to garbage (which
it's not that correct and can lead to corruption). It's now fixed in CVS
(0.64). It do not seems to cause problem in 0.63...

freddy77