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

[Eli Friedman via cfe-commits]

================
@@ -750,6 +750,19 @@ 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 had errors.
+      if (Field->getInClassInitializer() &&
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efriedma-quic wrote:

I'm not sure I understand the purpose of this code.  Why are we not handling this in BuildCXXDefaultInitExpr()?

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