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

[Erich Keane via cfe-commits]

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@@ -20,6 +20,20 @@ class SpaceShipDefaultCompare {
   int operator<=>(const SpaceShipDefaultCompare &) const = default;
 };
 
+class EqDefaultCompareOutOfClass {
+  int used;
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erichkeane wrote:

A comment here pointing out that we're validating that `used` doesn't get diagnosed would be helpful.

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