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

[Fangrui Song via llvm-commits]

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@@ -566,6 +570,7 @@ constexpr const char *knownZFlags[] = {
     "origin",
     "pac-plt",
     "pack-relative-relocs",
+    "pack-relative-auth-relocs",
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MaskRay wrote:

Is there justification for adding a new option?
Why can't we just use `pack-relative-relocs`?
This is a new ABI and we are adding stuff that existing linkers don't know, so there isn't any compatibility concern.

If there is sufficient justification for a new option, we should have agreement with binutils folks on the name.


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