[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 #20 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
> 
> Jakub Jelinek <jakub at gcc dot gnu.org> changed:
> 
>            What    |Removed                     |Added
> ----------------------------------------------------------------------------
>                  CC|                            |mark at gcc dot gnu.org
> 
> --- Comment #19 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
> I think a destructor is too risky here.
> Can't you just register with valgrind a pointer known not to be freed at exit?
> Would be nice to have something like __libc_freeres for libstdc++ too, that
> valgrind/mtrace/LeakSanitizer could invoke.
> I'm afraid tons of programs just do busy work in various threads until some
> thread exits the whole app, and your change could break it.

It indeed would free memory of in-flight exceptions.  Which means that
process termination in OOM situations might become interesting?

OTOH we now leak with dlopen/dlclose of libstdc++.so (just consider
doing that multiple times).