[clang] [clang] Fix a crash issue that caused by handling of fields with initializers in nested anonymous unions (PR #113049)

[Haojian Wu via cfe-commits]

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@@ -750,6 +750,18 @@ void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
     if (Field->hasInClassInitializer()) {
       if (VerifyOnly)
         return;
+
+      // We do not want to aggressively set the hadError flag and cutoff
+      // parsing. Try to recover when in-class-initializer is a RecoveryExpr.
+      if (isa_and_nonnull<RecoveryExpr>(Field->getInClassInitializer())) {
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hokein wrote:

It is unclear to me why we need to check the specific `RecoveryExpr`? Can we just use the `Field->getInClassInitializer()->containsErrors()`?

https://github.com/llvm/llvm-project/pull/113049