[libcxx-commits] [libcxxabi] [libc++abi] Always use thread_local for cxa_exception_storage (PR #79868)

[Sean Perry via libcxx-commits]

perry-ca wrote:

> @perry-ca @zibi2 Is there a timeline for adding support for TLS? TLS is technically a required part of the spec since it's mentioned in the spec, and it would be nice to drive towards that on all platforms whenever possible.
> 
The currently supported versions of z/OS are LE 2.4, LE 2.5 and LE 3.1.  TLS is supported in LE 3.1 (no C++ ctors/dtors) but not LE 2.4 or 2.5.  The libc++ library needs to run on all of these versions of z/OS.  We will need to continue building with the pthread method for a number of years until LE 2.5 is out of service and we no longer support that version of LE.  

> Also, in your build where do you define `HAS_THREAD_LOCAL`? It's currently dead code since nothing else in the code defines that macro, it would be nice to make that less hacky.

We don't define this macro.  We use the code in the `#else` block.  



https://github.com/llvm/llvm-project/pull/79868