[libunwind] [libunwind] Fix exposure of UNW_AARCH64_RA_SIGN_STATE through _Unwind… (PR #205188)

[Jon Roelofs via cfe-commits]

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@@ -0,0 +1,155 @@
+// -*- C++ -*-
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jroelofs wrote:

The usual reason to compile C-flavored code as C++ in unwinder tests is because on some platforms, the unwind tables are not emitted by default for C. All the rest of the tests here are either the same C++ style, or they're pure ASM, so I'm inclined to leave it as is for consistency.

https://github.com/llvm/llvm-project/pull/205188