[Bug libstdc++/21334] Lack of Posix compliant thread safety in std::basic_string

["pcarlini at suse dot de" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From pcarlini at suse dot de  2005-05-03 09:29 -------
> I'm not sure what sort of help you are looking for.  I thought
> that I very clearly pointed out the problem, and the point in
> the code where it occured.

Ok, my message was not clear. I'm looking for help about the
*performance* issue, not the correctness issue. To your best
knowledge all those users that avoid v3 basic_string for MT
applications do that for performance or for correctness (wrt
the Posix issue that you are pointing out in detail)?? Reading
those papers that I mentioned before (+ another one on C/C++
Users Journal which exactly touches *your* issue) it's *not*
at all clear that the latter is the main issue, in the general
understanding.

> It would help.  But an implementation designed with reference
> counting in mind is likely to be rather slow when reference
> counting is turned off.  IMHO, correct and slow is better than
> the current situation, but not all compiler users agree.

Indeed. Of course I'm talking about a *switch* (off by default)
But, about the correctness point...

> Most other implementations I'm aware of don't use std::string in
> exceptions.  That would seem to be the best solution.

Ok, but I don't think we can also change that in the short term
and not affecting the ABI, we are definitely going to do that in
v7-branch and I would appreciate if you could advise about the
best solution among all those proposed (see the thread).

Returning to our issue, however, do you still believe that a
switch turning off RC would be useful if we don't change the
treatment of exceptions? I don't know, maybe we can have 
something simple for that within the present ABI, but I cannot
make promises and want to have an idea of the amount of work.

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21334