diff --git a/mlir/lib/Bindings/Python/IRCore.cpp b/mlir/lib/Bindings/Python/IRCore.cpp
index b46fe44e9e19f..794be974284cd 100644
--- a/mlir/lib/Bindings/Python/IRCore.cpp
+++ b/mlir/lib/Bindings/Python/IRCore.cpp
@@ -841,7 +841,7 @@ py::tuple PyDiagnostic::getNotes() {
   materializedNotes = py::tuple(numNotes);
   for (intptr_t i = 0; i < numNotes; ++i) {
     MlirDiagnostic noteDiag = mlirDiagnosticGetNote(diagnostic, i);
-    materializedNotes.value()[i] = PyDiagnostic(noteDiag);
+    (*materializedNotes)[i] = PyDiagnostic(noteDiag);
   }
   return *materializedNotes;
 }
diff --git a/mlir/lib/Bindings/Python/IRModule.h b/mlir/lib/Bindings/Python/IRModule.h
index 4738a6fae78cf..2492ad5d1f277 100644
--- a/mlir/lib/Bindings/Python/IRModule.h
+++ b/mlir/lib/Bindings/Python/IRModule.h
@@ -302,7 +302,7 @@ class PyDiagnostic {
   /// If notes have been materialized from the diagnostic, then this will
   /// be populated with the corresponding objects (all castable to
   /// PyDiagnostic).
-  llvm::Optional<pybind11::tuple> materializedNotes;
+  std::optional<pybind11::tuple> materializedNotes;
   bool valid = true;
 };