[lld] [lld][AArch64][ELF][PAC] Support AUTH relocations and AUTH ELF marking (PR #72714)

[Fangrui Song via llvm-commits]

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@@ -591,15 +603,15 @@ class AndroidPackedRelocationSection final : public RelocationBaseSection {
 };
 
 struct RelativeReloc {
-  uint64_t getOffset() const { return inputSec->getVA(offsetInSec); }
+  uint64_t getOffset() const { return inputSec->getVA(reloc->offset); }
 
   const InputSectionBase *inputSec;
-  uint64_t offsetInSec;
+  Relocation *reloc;
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MaskRay wrote:

I agree that RelativeReloc needs more information but the current code doesn't work. `&isec.relocs().back()` can will become dangling if the `relocations` variable gets resized.

https://github.com/llvm/llvm-project/pull/72714