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

[Oliver Hunt via llvm-commits]

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@@ -83,7 +83,13 @@ __llvm_profile_iterate_data(const __llvm_profile_data *Data) {
 /* This method is only used in value profiler mock testing.  */
 COMPILER_RT_VISIBILITY void *
 __llvm_get_function_addr(const __llvm_profile_data *Data) {
-  return Data->FunctionPointer;
+  void *FP = Data->FunctionPointer;
+#if __has_feature(ptrauth_calls)
+  // This is only used for tests where we compare against what happens to be
+  // signed pointers.
+  FP = ptrauth_sign_unauthenticated(FP, VALID_CODE_KEY, 0);
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ojhunt wrote:

hmmm, I'll see if this actually caused any of the bot failures, and if it's not responsible for any I'll try to work out why

@kovdan01 @asl do you folk have a vm setup you can test on? I realize I'm currently limited to building for darwin so it's easy for me to luck out on implicit/transitive includes from other places.

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