[clang] [Clang] Handle structs with inner structs and no fields (PR #89126)

[Eli Friedman via cfe-commits]

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@@ -826,29 +826,32 @@ const FieldDecl *CodeGenFunction::FindFlexibleArrayMemberField(
     ASTContext &Ctx, const RecordDecl *RD, StringRef Name, uint64_t &Offset) {
   const LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel =
       getLangOpts().getStrictFlexArraysLevel();
-  unsigned FieldNo = 0;
-  bool IsUnion = RD->isUnion();
+  uint32_t FieldNo = 0;
 
-  for (const Decl *D : RD->decls()) {
-    if (const auto *Field = dyn_cast<FieldDecl>(D);
-        Field && (Name.empty() || Field->getNameAsString() == Name) &&
+  if (RD->isImplicit())
+    return nullptr;
+
+  for (const FieldDecl *FD : RD->fields()) {
+    if ((Name.empty() || FD->getNameAsString() == Name) &&
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efriedma-quic wrote:

Minor question I thought of looking at this one more time for the backport; why are we checking the name of the FieldDecl, instead just checking pointer equality? The caller has a FieldDecl, I think.

https://github.com/llvm/llvm-project/pull/89126