diff --git a/tensorflow/core/common_runtime/gpu/gpu_adjustable_allocator.h b/tensorflow/core/common_runtime/gpu/gpu_adjustable_allocator.h
index 4d675aad5ec..9bca4cf9d98 100644
--- a/tensorflow/core/common_runtime/gpu/gpu_adjustable_allocator.h
+++ b/tensorflow/core/common_runtime/gpu/gpu_adjustable_allocator.h
@@ -46,6 +46,7 @@ class GPUAdjustableAllocator final {
   size_t FreeEmptyMemory(size_t target_memory_bytes,
                          BFCAllocator* bfc_allocator)
       EXCLUSIVE_LOCKS_REQUIRED(lock_);
+    mutex lock_;
 };
 
 }  // namespace tensorflow