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

[Anatoly Trosinenko via llvm-commits]

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@@ -129,26 +129,29 @@ struct UnwindInfoSections {
     defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) ||                              \
     defined(_LIBUNWIND_USE_DL_ITERATE_PHDR)
   // No dso_base for SEH.
-  uintptr_t       dso_base;
+  uintptr_t __ptrauth_unwind_info_section_dso_base dso_base = 0;
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atrosinenko wrote:

Is zero-initialization added intentionally here and below?

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