[compiler-rt] [libcxxabi] [libunwind] [runtimes][PAC] Harden unwinding when possible (#138571) (PR #143230)

[Daniil Kovalev via cfe-commits]

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@@ -109,4 +110,38 @@
 #  define _LIBCXXABI_NOEXCEPT noexcept
 #endif
 
+#if __has_include(<ptrauth.h>)
+#  include <ptrauth.h>
+#endif
+
+#if defined(__APPLE__) && __has_feature(ptrauth_qualifier)
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kovdan01 wrote:

It looks like that `__has_feature(ptrauth_qualifier)` should be replaced with `__has_extension(ptrauth_qualifier)`. It is defined as `EXTENSION` in clang/include/clang/Basic/Features.def, and existing tests use `__has_extension` instead of `__has_feature` for this.

https://github.com/llvm/llvm-project/pull/143230