[clang] [Clang][attr] Add 'kcfi_salt' attribute (PR #141846)

[Aaron Ballman via cfe-commits]

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@@ -3929,6 +3929,14 @@ def CFICanonicalJumpTable : InheritableAttr {
   let SimpleHandler = 1;
 }
 
+def CFISalt : DeclOrTypeAttr {
+  let Spellings = [Clang<"cfi_salt">];
+  let Args = [StringArgument<"Salt">];
+  let Subjects = SubjectList<[Function, Field, Var, TypedefName], ErrorDiag>;
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AaronBallman wrote:

I would expect those cases to work, at least with the `[[]]` spelling because that applies the attribute to the type spelled immediately on its left. Those should both resolve to `fp_t __cfi_salt` aka `int (*)(void) __cfi_salt`

https://github.com/llvm/llvm-project/pull/141846