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

[Oliver Hunt via llvm-commits]

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@@ -30,6 +30,46 @@ EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD, void *, PCONTEXT,
                                             _Unwind_Personality_Fn);
 #endif
 
+#if __has_include(<ptrauth.h>)
+#include <ptrauth.h>
+#endif
+
+#if defined(__APPLE__) && __has_feature(ptrauth_qualifier)
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ojhunt wrote:

yeah, I wonder if there's any existing precedence for cmake variables the apply to all the runtimes?

Also, given some of the other issues you've hit with building don't expend too much effort trying to build/test - I need to work out what parts I've managed to screw up while building out this PR - some of the issues you've hit seem likely to be me screwing up during the preparation of the PR and I don't want you folk to slog through issues caused by my muppetry

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