[clang] [Clang][Sema] Diagnose class member access expressions naming non-existent members of the current instantiation prior to instantiation in the absence of dependent base classes (PR #84050)

[Erich Keane via cfe-commits]

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@@ -990,6 +970,18 @@ Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType,
                                const Scope *S,
                                bool SuppressQualifierCheck,
                                ActOnMemberAccessExtraArgs *ExtraArgs) {
+  assert(!SS.isInvalid() && "nested-name-specifier cannot be invalid");
+  if (R.wasNotFoundInCurrentInstantiation() ||
+#if 0
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erichkeane wrote:

Oh?

https://github.com/llvm/llvm-project/pull/84050