[Bug libitm/55693] [4.8 Regression] libitm.c++/eh-1.C execution test fails on darwin from r193271

[iains at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55693

--- Comment #21 from Iain Sandoe <iains at gcc dot gnu.org> 2013-01-23 08:44:45 UTC ---
(In reply to comment #20)
> crttme.o comes from libgcc/config/darwin-crt-tm.c, which has:
> 
> /* Provide dummy functions to satisfy linkage for versions of the Darwin 
>    tool-chain that that can't handle undefined weak refs at the link stage.
>    ??? Define these dummy functions only when !HAVE_ELF_STYLE_WEAKREF. */
> 
> extern void *__cxa_allocate_exception (size_t) WEAK;
> ...
> ...
> void *__cxa_allocate_exception (size_t s UNUSED) { return NULL; }
> 
> This looks like the NULL returning __cxa_allocate_exception that is causing all
> this grief, and came from Patrick Marlier and Iain Sandoe's patch here:
> 
> http://gcc.gnu.org/ml/gcc-patches/2012-02/msg00851.html
> 
> Again, I'm a Darwin wimp.  Anyone care to comment?

looks like (yet another) permutation of what works/doesn't with "ELF-style weak
linking" I don't have darwin11 or 12 (yet) - but should do soon.