[Bug target/113874] GNU2 TLS descriptor calls do not follow psABI on x86_64-linux-gnu

["hjl.tools at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113874

--- Comment #33 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to H.J. Lu from comment #32)
> (In reply to Michael Matz from comment #31)
> > (In reply to H.J. Lu from comment #30)
> > > (In reply to Michael Matz from comment #29)
> > > > It not only can call malloc.  As the backtrace of H.J. shows, it quite
> > > > clearly _does_ so :-)
> > > 
> > > ld.so can only call the malloc implementation internal to ld.so.
> > 
> > (And string functions for initializing that memory)  If that's ensured
> > already
> > everywhere: super.  Because I agree, that this is the best thing to do here.
> > From my perspective this is pure internal implementation details and hence
> > setting up thread-local areas should not be expected to be interposable by
> > users.
> > (a custom allocator that isn't malloc or doesn't interact with it also would
> > work)
> 
> Since ia32 ld.so in glibc is compiled with:
> 
> Makefile:rtld-CFLAGS += -mno-sse -mno-mmx -mfpmath=387
> 
> ia32 _dl_tlsdesc_dynamic is OK.

387 registers may be an issue.