[clang] [Clang] Only ignore special methods for unused private fields in BuildFieldReferenceExpr (PR #116965)

[Mészáros Gergely via cfe-commits]

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@@ -20,6 +20,20 @@ class SpaceShipDefaultCompare {
   int operator<=>(const SpaceShipDefaultCompare &) const = default;
 };
 
+class EqDefaultCompareOutOfClass {
+  int used; // no warning
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Maetveis wrote:

Okay, sorry I wasn't sure what you were referring to, but I get know that from the change-set it is not obvious how / why the issue in #116961 is fixed by this change and why it is a special case not covered by the current testing. I expanded quite a bit on the comment, hopefully it did not become too verbose now.

https://github.com/llvm/llvm-project/pull/116965