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

[Anatoly Trosinenko via llvm-commits]

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@@ -129,26 +129,38 @@ struct UnwindInfoSections {
     defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) ||                              \
     defined(_LIBUNWIND_USE_DL_ITERATE_PHDR)
   // No dso_base for SEH.
-  uintptr_t       dso_base;
+  uintptr_t
+      __LIBUNWIND_PTRAUTH_RI_PDD("UnwindInfoSections::dso_base") dso_base = 0;
 #endif
 #if defined(_LIBUNWIND_USE_DL_ITERATE_PHDR)
-  size_t          text_segment_length;
+  size_t __LIBUNWIND_PTRAUTH_RI_PDD("UnwindInfoSections::text_segment_length")
+      text_segment_length = 0;
 #endif
 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
-  uintptr_t       dwarf_section;
-  size_t          dwarf_section_length;
+  uintptr_t __LIBUNWIND_PTRAUTH_RI_PDD("UnwindInfoSections::dwarf_section")
+      dwarf_section = 0;
+  size_t __LIBUNWIND_PTRAUTH_RI_PDD("UnwindInfoSections::dwarf_section_length")
+      dwarf_section_length = 0;
 #endif
 #if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX)
-  uintptr_t       dwarf_index_section;
-  size_t          dwarf_index_section_length;
+  uintptr_t __LIBUNWIND_PTRAUTH_RI_PDD(
+      "UnwindInfoSections::dwarf_index_section") dwarf_index_section = 0;
+  size_t __LIBUNWIND_PTRAUTH_RI_PDD(
+      "UnwindInfoSections::dwarf_index_section_length")
+      dwarf_index_section_length = 0;
 #endif
 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND)
-  uintptr_t       compact_unwind_section;
-  size_t          compact_unwind_section_length;
+  uintptr_t __LIBUNWIND_PTRAUTH_RI_PDD(
+      "UnwindInfoSections::compact_unwind_section") compact_unwind_section = 0;
+  size_t __LIBUNWIND_PTRAUTH_RI_PDD(
+      "UnwindInfoSections::compact_unwind_section_length")
+      compact_unwind_section_length = 0;
 #endif
 #if defined(_LIBUNWIND_ARM_EHABI)
-  uintptr_t       arm_section;
-  size_t          arm_section_length;
+  uintptr_t __LIBUNWIND_PTRAUTH_RI_PDD("UnwindInfoSections::arm_section")
+      arm_section = 0;
+  size_t __LIBUNWIND_PTRAUTH_RI_PDD("UnwindInfoSections::arm_section_length")
+      arm_section_length = 0;
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atrosinenko wrote:

These two fields doesn't seem to be used on AArch64.

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