Index: mlir/include/mlir/TableGen/Dialect.h
===================================================================
--- mlir/include/mlir/TableGen/Dialect.h
+++ mlir/include/mlir/TableGen/Dialect.h
@@ -107,6 +107,8 @@
   // Returns whether the dialect is defined.
   explicit operator bool() const { return def != nullptr; }
 
+  const llvm::Record &getDef() const { return *def; }
+
 private:
   const llvm::Record *def;
   std::vector<StringRef> dependentDialects;
Index: mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
===================================================================
--- mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
+++ mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
@@ -2330,6 +2330,20 @@
     return;
 
   Dialect::FolderAPI folderApi = op.getDialect().getFolderAPI();
+  if (folderApi == Dialect::FolderAPI::RawAttributes) {
+    static bool emitted = false;
+    if (!emitted) {
+      emitted = true;
+      llvm::PrintWarning(op.getDialect().getDef().getLoc(),
+                         "'useFoldAPI' of 'kEmitRawAttributesFolder' (default) "
+                         "has been deprecated and is pending removal. Please "
+                         "switch to 'kEmitFoldAdaptorFolder'. See "
+                         "https://discourse.llvm.org/t/"
+                         "psa-new-improved-fold-method-signature-has-landed-"
+                         "please-update-your-downstream-projects/67618");
+    }
+  }
+
   SmallVector<MethodParameter> paramList;
   if (folderApi == Dialect::FolderAPI::RawAttributes)
     paramList.emplace_back("::llvm::ArrayRef<::mlir::Attribute>", "operands");