[PR19826] fix non-LE TLS in static programs

[Florian Weimer]

On 12/06/2016 07:56 AM, Alexandre Oliva wrote:
> On Dec  2, 2016, Florian Weimer <fweimer@redhat.com> wrote:
>> What's the status here?  It seems that Alexandre committed it on
>> September 22nd, despite Torvald's objections.
>
> No, I committed the *first* of two patches, that I'd posted on 2016-09-20.
> https://sourceware.org/ml/libc-alpha/2016-09/msg00365.html

I'm sorry I reconstructed the history here incorrectly.

>> This patch broke non-optimized global-dynamic TLS on aarch64 (for
>> shared builds), as shown by my new tst-tls-manydynamic test case.
>
> Would you please try the second patch and confirm that it fixes the
> problem?

If I revert the change to allocatestack.c, the test case passes.

> What you're hitting is most likely the DTV resizing race
> condition described in the comments there, at the '(**)' note.

It's not even a race.  The test case serializes DTV access externally, 
and still fails.  So the comment about a race is rather misleading.

Thanks,
Florian