[clang] [Sema] Instantiate destructors for initialized anonymous union fields (PR #128866)

[Eli Friedman via cfe-commits]

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@@ -5451,10 +5451,23 @@ bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
            NumInitializers * sizeof(CXXCtorInitializer*));
     Constructor->setCtorInitializers(baseOrMemberInitializers);
 
+    SourceLocation Location = Constructor->getLocation();
+
+    for (CXXCtorInitializer *Initializer : Info.AllToInit) {
+      FieldDecl *Field = Initializer->getAnyMember();
+      if (!Field)
+        continue;
+
+      RecordDecl *FieldRecordDecl = Field->getParent();
+      if (!FieldRecordDecl->isUnion() ||
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efriedma-quic wrote:

The `member with destructor not allowed in anonymous aggregate` error is separate from what we're trying to do here; I'd say don't worry about it.

https://github.com/llvm/llvm-project/pull/128866