Re: [PATCH] elf: Assume TLS is initialized in _dl_map_object_from_fd

[Florian Weimer <fweimer at redhat dot com>]

On 11/14/2016 03:57 PM, Florian Weimer wrote:
> On 11/11/2016 10:17 PM, Florian Weimer wrote:
>
> > And so on.  My question is this: Can we actually enter the final part,
> > under “We can do the TLS right now!” in a shared build?
> >
> > I doubt that because during the initial link, we will hit the second
> > break statement for libraries, and the third break statement for the
> > main program.  Before user code runs, rtld.c sets up the TLS data
> > structures, so any future dlopen calls hit the second break again
> > because GL(dl_tls_dtv_slotinfo_list) != NULL at this point.
> >
> > Is this reasoning correct?  I put in a debug printf and ran the elf
> > tests, and there was nothing printed.
>
> I've simplified the code accordingly and added asserts.
>
> I have verified that the elf/* test suite still passes on s390, s390x,
> ppc64, ppc, x86_64, i386.  On x86_64, I also performed an installed-tree
> test (and the assert did not fire).

I will check this in soon unless someone objects.

TLS initialization has P&C issues, and I hope this cleanup makes it 
easier to fix that.  (It is impossible to review dead code for P&C issues.)

Thanks,
Florian