[PATCH] libstdc++: Hide TLS variables in `std::call_once`

[Martin Storsjö]

On Wed, 2 Apr 2025, Martin Storsjö wrote:

> On Fri, 29 Nov 2024, LIU Hao wrote:
>
>> 在 2024-11-29 23:50, Jonathan Wakely 写道:
>>>> It looks like your patch is against gcc-14 not trunk, the
>>>> GLIBCXX_15.1.0 version is already there.
>>> 
>>> Sorry, I mean GLIBCXX_3.4.34 for 15.1.0
>> 
>> Oops that's what I used to test the patch. Reapplied to master now.
>
> Ping - what's the status of this patch?
>
> It would be nice to switch to the new ABI structure for std::call_once as 
> soon as possible, to ease a future switch to native TLS on mingw targets, 
> once https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80881 is done. (This quirk 
> with the exposed cross-DLL TLS data in std::call_once also comes up in a 
> number of other situations on mingw, so it would be nice to switch to the new 
> form where it is hidden.)

Ping; the Windows TLS patch has been merged now, and this patch is needed 
for having a working libstdc++ in that build configuration.

// Martin