[clang] [PAC] Add support for __ptrauth type qualifier (PR #100830)

[Aaron Ballman via cfe-commits]

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@@ -980,6 +980,25 @@ def err_ptrauth_indirect_goto_addrlabel_arithmetic : Error<
   "%select{subtraction|addition}0 of address-of-label expressions is not "
   "supported with ptrauth indirect gotos">;
 
+// __ptrauth qualifier
+def err_ptrauth_qualifier_invalid : Error<
+  "%select{return types|parameter types|properties}1 may not be qualified with __ptrauth; type is %0">;
+def err_ptrauth_qualifier_cast : Error<
+  "cast types may not be qualified with __ptrauth; type is %0">;
+def err_ptrauth_qualifier_nonpointer : Error<
+  "__ptrauth qualifier may only be applied to pointer types; type here is %0">;
----------------
AaronBallman wrote:

```suggestion
  "'__ptrauth' qualifier only applies to pointer types; %0 is invalid">;
```

https://github.com/llvm/llvm-project/pull/100830