[clang] [clang] Function type attribute to prevent CFI instrumentation (PR #135836)

[Paul Kirth via cfe-commits]

================
@@ -12711,6 +12711,11 @@ def warn_noderef_on_non_pointer_or_array : Warning<
 def warn_noderef_to_dereferenceable_pointer : Warning<
   "casting to dereferenceable pointer removes 'noderef' attribute">, InGroup<NoDeref>;
 
+def warn_cast_discards_cfi_unchecked_callee
+    : Warning<"implicit conversion from %0 to %1 discards "
+              "`cfi_unchecked_callee` attribute">,
----------------
ilovepi wrote:

These look like backticks ... should they be single quotes? That's the pattern I see above for `noderef`. Was wondering if that's why the docs build broke in the premerge check.
```suggestion
              "'cfi_unchecked_callee' attribute">,
```

https://github.com/llvm/llvm-project/pull/135836