diff --git a/torch_xla/csrc/ops/select.cpp b/torch_xla/csrc/ops/select.cpp
index 8e673bc21161..67c02fc177b1 100644
--- a/torch_xla/csrc/ops/select.cpp
+++ b/torch_xla/csrc/ops/select.cpp
@@ -34,35 +34,35 @@ XlaOpVector Select::Lower(LoweringContext* loctx) const {
     return ReturnOp(output, loctx);
   } else {
     // When input has unbounded dynamic dim and target dim is the unbounded
-    // dim, slice full range along the dynamic dim.
-    // TODO: support slice a constant size from unbounded dynamic dim. This
-    // Requires passing additional info from LTC to XLA Node.
+    // dim, slice full range along the dynamic dim. We will assert now.
     std::vector<int32_t> start_vec(input_shape.rank(), 0);
     start_vec[dim_] = start_;
-    xla::XlaOp starts = xla::ConstantR1(input.builder(),
-      absl::Span<const int32_t>(start_vec));
+    xla::XlaOp starts =
+        xla::ConstantR1(input.builder(), absl::Span<const int32_t>(start_vec));
     std::vector<int32_t> stride_vec(input_shape.rank(), 1);
     stride_vec[dim_] = GetStride(start_, end_, stride_);
-    xla::XlaOp strides = xla::ConstantR1(input.builder(),
-      absl::Span<const int32_t>(stride_vec));
-    xla::Shape final_shape = MakeSelectShape(input_shape, dim_, start_, end_,
-                                       stride_);
+    xla::XlaOp strides =
+        xla::ConstantR1(input.builder(), absl::Span<const int32_t>(stride_vec));
+    xla::Shape final_shape =
+        MakeSelectShape(input_shape, dim_, start_, end_, stride_);
     std::vector<xla::XlaOp> limit_ops;
     for (int i = 0; i < input_shape.rank(); ++i) {
       if (input_shape.is_unbounded_dynamic_dimension(i)) {
         limit_ops.push_back(xla::Reshape(xla::GetDimensionSize(input, i), {1}));
         final_shape.set_unbounded_dynamic_dimension(i);
+        XLA_CHECK(dim_ != i)
+            << "Selecting unbounded dimension is not supported.";
       } else {
         int32_t limit = i == dim_ ? end_ : input_shape.dimensions(i);
-        limit_ops.push_back(xla::ConstantR1(input.builder(),
-                            absl::Span<const int32_t>({limit})));
+        limit_ops.push_back(xla::ConstantR1(
+            input.builder(), absl::Span<const int32_t>({limit})));
       }
     }
     xla::XlaOp concat_limit = xla::ConcatInDim(input.builder(), limit_ops, {0});
-    xla::XlaOp output = xla::CustomCall(
-      input.builder(), "mhlo.real_dynamic_slice",
-      /*operands=*/ {input, starts, concat_limit, strides},
-      /*shape*/ final_shape);
+    xla::XlaOp output =
+        xla::CustomCall(input.builder(), "mhlo.real_dynamic_slice",
+                        /*operands=*/{input, starts, concat_limit, strides},
+                        /*shape*/ final_shape);
     return ReturnOp(output, loctx);
   }
 }
diff --git a/torch_xla/csrc/runtime/stablehlo_helper.cc b/torch_xla/csrc/runtime/stablehlo_helper.cc
index dc3259875acf..74ae3cde2470 100644
--- a/torch_xla/csrc/runtime/stablehlo_helper.cc
+++ b/torch_xla/csrc/runtime/stablehlo_helper.cc
@@ -77,12 +77,13 @@ static absl::Status ConvertHloToMhlo(const xla::HloModuleProto* proto,
 static absl::Status mhloToStablehloHelper(mlir::ModuleOp* mlir_module,
                                           mlir::MLIRContext* context) {
   mlir::PassManager pm(context);
-  // legalize `mhlo.dot` to `mhlo.dot_general` to workaround the shape refinement
-  // issue in `stablehlo.dot`.
-  // TODO(lsy323): Remove this pass when mhlo.dot will can be leagalized to 
+  // legalize `mhlo.dot` to `mhlo.dot_general` to workaround the shape
+  // refinement issue in `stablehlo.dot`.
+  // TODO(lsy323): Remove this pass when mhlo.dot will can be leagalized to
   // stablehlo.dot_general in MHLO->StableHLO converter. Or shape refinement
   // logic is fixed for stablehlo.dot.
-  pm.addNestedPass<mlir::func::FuncOp>(mlir::mhlo::createLegalizeDotToDotGeneralPass());
+  pm.addNestedPass<mlir::func::FuncOp>(
+      mlir::mhlo::createLegalizeDotToDotGeneralPass());
   // Apply pass to remove HLO tuple output, as MHLO/StableHLO supports multiple
   // outputs.
   pm.addPass(mlir::mhlo::createExpandHloTuplesPass());