[clang] [AArch64][PAC][clang][ELF] Support PAuth ABI compatibility tag (PR #85235)

[Fangrui Song via cfe-commits]

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@@ -7203,6 +7203,33 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                    options::OPT_fno_ptrauth_intrinsics, false))
     CmdArgs.push_back("-fptrauth-intrinsics");
 
+  if (Args.hasFlag(options::OPT_fptrauth_calls, options::OPT_fno_ptrauth_calls,
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MaskRay wrote:

This should be added in Clang::AddAArch64TargetArgs and use addOptInFlag. See 6ff61914a1ef2c05702ba73cf31ffdeed59c1740

https://github.com/llvm/llvm-project/pull/85235