diff --git a/muduo/base/Thread.cc b/muduo/base/Thread.cc
index c8a052eeb..e8e581175 100644
--- a/muduo/base/Thread.cc
+++ b/muduo/base/Thread.cc
@@ -63,26 +63,25 @@ struct ThreadData
   typedef muduo::Thread::ThreadFunc ThreadFunc;
   ThreadFunc func_;
   string name_;
-  std::weak_ptr<pid_t> wkTid_;
+  pid_t* tid_;
+  CountDownLatch* latch_;
 
   ThreadData(ThreadFunc func,
              const string& name,
-             const std::shared_ptr<pid_t>& tid)
+             pid_t* tid,
+             CountDownLatch* latch)
     : func_(std::move(func)),
       name_(name),
-      wkTid_(tid)
+      tid_(tid),
+      latch_(latch)
   { }
 
   void runInThread()
   {
-    pid_t tid = muduo::CurrentThread::tid();
-
-    std::shared_ptr<pid_t> ptid = wkTid_.lock();
-    if (ptid)
-    {
-      *ptid = tid;
-      ptid.reset();
-    }
+    *tid_ = muduo::CurrentThread::tid();
+    tid_ = NULL;
+    latch_->countDown();
+    latch_ = NULL;
 
     muduo::CurrentThread::t_threadName = name_.empty() ? "muduoThread" : name_.c_str();
     ::prctl(PR_SET_NAME, muduo::CurrentThread::t_threadName);
@@ -156,9 +155,10 @@ Thread::Thread(ThreadFunc func, const string& n)
   : started_(false),
     joined_(false),
     pthreadId_(0),
-    tid_(new pid_t(0)),
+    tid_(0),
     func_(std::move(func)),
-    name_(n)
+    name_(n),
+    latch_(1)
 {
   setDefaultName();
 }
@@ -187,13 +187,18 @@ void Thread::start()
   assert(!started_);
   started_ = true;
   // FIXME: move(func_)
-  detail::ThreadData* data = new detail::ThreadData(func_, name_, tid_);
+  detail::ThreadData* data = new detail::ThreadData(func_, name_, &tid_, &latch_);
   if (pthread_create(&pthreadId_, NULL, &detail::startThread, data))
   {
     started_ = false;
     delete data; // or no delete?
     LOG_SYSFATAL << "Failed in pthread_create";
   }
+  else
+  {
+    latch_.wait();
+    assert(tid_ > 0);
+  }
 }
 
 int Thread::join()
diff --git a/muduo/base/Thread.h b/muduo/base/Thread.h
index b5ac4dad6..36efd5e56 100644
--- a/muduo/base/Thread.h
+++ b/muduo/base/Thread.h
@@ -7,6 +7,7 @@
 #define MUDUO_BASE_THREAD_H
 
 #include <muduo/base/Atomic.h>
+#include <muduo/base/CountDownLatch.h>
 #include <muduo/base/Types.h>
 
 #include <functional>
@@ -30,7 +31,7 @@ class Thread : noncopyable
 
   bool started() const { return started_; }
   // pthread_t pthreadId() const { return pthreadId_; }
-  pid_t tid() const { return *tid_; }
+  pid_t tid() const { return tid_; }
   const string& name() const { return name_; }
 
   static int numCreated() { return numCreated_.get(); }
@@ -41,9 +42,10 @@ class Thread : noncopyable
   bool       started_;
   bool       joined_;
   pthread_t  pthreadId_;
-  std::shared_ptr<pid_t> tid_;
+  pid_t      tid_;
   ThreadFunc func_;
   string     name_;
+  CountDownLatch latch_;
 
   static AtomicInt32 numCreated_;
 };
diff --git a/muduo/base/tests/Thread_test.cc b/muduo/base/tests/Thread_test.cc
index 2bbc10ab9..36c32b356 100644
--- a/muduo/base/tests/Thread_test.cc
+++ b/muduo/base/tests/Thread_test.cc
@@ -55,11 +55,13 @@ int main()
 
   muduo::Thread t1(threadFunc);
   t1.start();
+  printf("t1.tid=%d\n", t1.tid());
   t1.join();
 
   muduo::Thread t2(std::bind(threadFunc2, 42),
                    "thread for free function with argument");
   t2.start();
+  printf("t2.tid=%d\n", t2.tid());
   t2.join();
 
   Foo foo(87.53);