[Bug libstdc++/64535] Emergency buffer for exception allocation too small

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64535

--- Comment #23 from rguenther at suse dot de <rguenther at suse dot de> ---
On Tue, 27 Jan 2015, jakub at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64535
> 
> --- Comment #22 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
> Can't you use a .bss object for the initial case, so you don't malloc anything
> in the ctor unless user requests something larger than that?

Is there a non-zeroed .bss section?  I think using dynamically allocated
memory might be cheaper.

But sure - it was a .bss object previously (four actually).

> That way "freeing" that would be handled in most cases.  And I assume you
> really can't dlclose libstdc++ while other threads are handling exceptions,
> because then those libraries should use libstdc++ entry points and either would
> need to be dlclosed too, or libstdc++ wouldn't be really unmapped.

Ok, so what's the real issue then with the destructor?  Don't we destroy
the global IO and locale stuff as well?