[libcxx-commits] [libcxx] [libc++] Document our ABI guarantees and what ABI flags exist to modify these guarantees (PR #132615)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,206 @@
+=======================
+libc++'s ABI Guarantees
+=======================
+
+libc++ provides multiple types of ABI guarantees. These include stability of the layout of structs, the linking of TUs
+built against different versions and configurations of the library, and more. This document describes what guarantees
+libc++ provides in these different fields as well as what options exist for users and vendors to affect these
----------------
ldionne wrote:

```suggestion
libc++ provides in these different areas as well as what options exist for vendors to affect these
```

https://github.com/llvm/llvm-project/pull/132615