[Bug c++/46097] Switch to warn of global variables in a C++ shared object

["noloader at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46097

--- Comment #3 from Jeffrey Walton <noloader at gmail dot com> 2010-10-20 17:38:59 UTC ---
(In reply to comment #2)
> (In reply to comment #1)
> > (In reply to comment #0)
> > > When a module meets the above compile and runtime requirements, a crash can
> > > occur in global objects with destructors when more than one process loads and
> > > subsequently unloads a shared object.
> > Are you saying independent processes interfere with each other?
> ...
> Crpyto++ has a test case demonstrating the RTLD_GLOBAL crash at [1]. [1] is
> accompanied by an analysis under GDB at [2]. Unfortunately, the test case is
> not minimal. It is based on the Crypto++ library and needs intermediate SOs to
> load the SO of interest. So the final executable never directly loads the
> Crypto++ shared object.
If a picture is worth a 1000 words, here's the scenario we are trying to
accomplist (to verify Crypto++ does not crash when unloaded). But keep in mind
that two distinct process will perform what's in the image.
http://www.cryptopp.com/wiki/File:Cryptopp-so-test.png