diff --git a/mlir/include/mlir/ExecutionEngine/AsyncRuntime.h b/mlir/include/mlir/ExecutionEngine/AsyncRuntime.h
--- a/mlir/include/mlir/ExecutionEngine/AsyncRuntime.h
+++ b/mlir/include/mlir/ExecutionEngine/AsyncRuntime.h
@@ -14,6 +14,7 @@
 #ifndef MLIR_EXECUTIONENGINE_ASYNCRUNTIME_H_
 #define MLIR_EXECUTIONENGINE_ASYNCRUNTIME_H_
 
+#include <cstddef>
 #include <stdint.h>
 
 #ifdef mlir_async_runtime_EXPORTS
@@ -38,7 +39,7 @@
 using AsyncValue = struct AsyncValue;
 
 // Async value payload stored in a memory owned by the async.value.
-using ValueStorage = void *;
+using ValueStorage = std::byte *;
 
 // Async runtime uses LLVM coroutines to represent asynchronous tasks. Task
 // function is a coroutine handle and a resume function that continue coroutine
diff --git a/mlir/lib/ExecutionEngine/AsyncRuntime.cpp b/mlir/lib/ExecutionEngine/AsyncRuntime.cpp
--- a/mlir/lib/ExecutionEngine/AsyncRuntime.cpp
+++ b/mlir/lib/ExecutionEngine/AsyncRuntime.cpp
@@ -199,7 +199,7 @@
   std::atomic<State::StateEnum> state;
 
   // Use vector of bytes to store async value payload.
-  std::vector<int8_t> storage;
+  std::vector<std::byte> storage;
 
   // Pending awaiters are guarded by a mutex.
   std::mutex mu;