diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 92f77fc..dd9983b 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,18 @@
 2019-10-29  Tom Tromey  <tromey@adacore.com>
 
+	* windows-nat.c (windows_add_thread, windows_delete_thread)
+	(windows_nat_target::fetch_registers)
+	(windows_nat_target::store_registers, fake_create_process)
+	(windows_nat_target::resume, windows_nat_target::resume)
+	(get_windows_debug_event, windows_nat_target::wait)
+	(windows_nat_target::pid_to_str)
+	(windows_nat_target::get_tib_address)
+	(windows_nat_target::get_ada_task_ptid)
+	(windows_nat_target::thread_name)
+	(windows_nat_target::thread_alive): Use lwp, not tid.
+
+2019-10-29  Tom Tromey  <tromey@adacore.com>
+
 	* windows-nat.c (handle_exception)
 	(windows_nat_target::thread_name): Update.
 	* nat/windows-nat.h (windows_thread_info): Remove destructor.
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index 12a69bb..b7c8ae5 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -422,9 +422,9 @@
   windows_thread_info *th;
   DWORD id;
 
-  gdb_assert (ptid.tid () != 0);
+  gdb_assert (ptid.lwp () != 0);
 
-  id = ptid.tid ();
+  id = ptid.lwp ();
 
   if ((th = thread_rec (id, FALSE)))
     return th;
@@ -486,9 +486,9 @@
 {
   DWORD id;
 
-  gdb_assert (ptid.tid () != 0);
+  gdb_assert (ptid.lwp () != 0);
 
-  id = ptid.tid ();
+  id = ptid.lwp ();
 
   /* Emit a notification about the thread being deleted.
 
@@ -565,7 +565,7 @@
 void
 windows_nat_target::fetch_registers (struct regcache *regcache, int r)
 {
-  DWORD tid = regcache->ptid ().tid ();
+  DWORD tid = regcache->ptid ().lwp ();
   windows_thread_info *th = thread_rec (tid, TRUE);
 
   /* Check if TH exists.  Windows sometimes uses a non-existent
@@ -635,7 +635,7 @@
 void
 windows_nat_target::store_registers (struct regcache *regcache, int r)
 {
-  DWORD tid = regcache->ptid ().tid ();
+  DWORD tid = regcache->ptid ().lwp ();
   windows_thread_info *th = thread_rec (tid, TRUE);
 
   /* Check if TH exists.  Windows sometimes uses a non-existent
@@ -1363,8 +1363,8 @@
       /*  We can not debug anything in that case.  */
     }
   current_thread
-    = windows_add_thread (ptid_t (current_event.dwProcessId, 0,
-				  current_event.dwThreadId),
+    = windows_add_thread (ptid_t (current_event.dwProcessId,
+				  current_event.dwThreadId, 0),
 			  current_event.u.CreateThread.hThread,
 			  current_event.u.CreateThread.lpThreadLocalBase,
 			  true /* main_thread_p */);
@@ -1421,10 +1421,10 @@
   last_sig = GDB_SIGNAL_0;
 
   DEBUG_EXEC (("gdb: windows_resume (pid=%d, tid=0x%x, step=%d, sig=%d);\n",
-	       ptid.pid (), (unsigned) ptid.tid (), step, sig));
+	       ptid.pid (), (unsigned) ptid.lwp (), step, sig));
 
   /* Get context for currently selected thread.  */
-  th = thread_rec (inferior_ptid.tid (), FALSE);
+  th = thread_rec (inferior_ptid.lwp (), FALSE);
   if (th)
     {
       if (step)
@@ -1458,7 +1458,7 @@
   if (resume_all)
     windows_continue (continue_status, -1, 0);
   else
-    windows_continue (continue_status, ptid.tid (), 0);
+    windows_continue (continue_status, ptid.lwp (), 0);
 }
 
 /* Ctrl-C handler used when the inferior is not run in the same console.  The
@@ -1537,7 +1537,7 @@
       /* Record the existence of this thread.  */
       thread_id = current_event.dwThreadId;
       th = windows_add_thread
-        (ptid_t (current_event.dwProcessId, 0, current_event.dwThreadId),
+        (ptid_t (current_event.dwProcessId, current_event.dwThreadId, 0),
 	 current_event.u.CreateThread.hThread,
 	 current_event.u.CreateThread.lpThreadLocalBase,
 	 false /* main_thread_p */);
@@ -1549,8 +1549,8 @@
 		     (unsigned) current_event.dwProcessId,
 		     (unsigned) current_event.dwThreadId,
 		     "EXIT_THREAD_DEBUG_EVENT"));
-      windows_delete_thread (ptid_t (current_event.dwProcessId, 0,
-				     current_event.dwThreadId),
+      windows_delete_thread (ptid_t (current_event.dwProcessId,
+				     current_event.dwThreadId, 0),
 			     current_event.u.ExitThread.dwExitCode,
 			     false /* main_thread_p */);
       th = &dummy_thread_info;
@@ -1568,8 +1568,8 @@
       current_process_handle = current_event.u.CreateProcessInfo.hProcess;
       /* Add the main thread.  */
       th = windows_add_thread
-        (ptid_t (current_event.dwProcessId, 0,
-		 current_event.dwThreadId),
+        (ptid_t (current_event.dwProcessId,
+		 current_event.dwThreadId, 0),
 	 current_event.u.CreateProcessInfo.hThread,
 	 current_event.u.CreateProcessInfo.lpThreadLocalBase,
 	 true /* main_thread_p */);
@@ -1590,8 +1590,8 @@
 	}
       else if (saw_create == 1)
 	{
-	  windows_delete_thread (ptid_t (current_event.dwProcessId, 0,
-					 current_event.dwThreadId),
+	  windows_delete_thread (ptid_t (current_event.dwProcessId,
+					 current_event.dwThreadId, 0),
 				 0, true /* main_thread_p */);
 	  ourstatus->kind = TARGET_WAITKIND_EXITED;
 	  ourstatus->value.integer = current_event.u.ExitProcess.dwExitCode;
@@ -1675,7 +1675,7 @@
     }
   else
     {
-      inferior_ptid = ptid_t (current_event.dwProcessId, 0, thread_id);
+      inferior_ptid = ptid_t (current_event.dwProcessId, thread_id, 0);
       current_thread = th;
       if (!current_thread)
 	current_thread = thread_rec (thread_id, TRUE);
@@ -1733,7 +1733,7 @@
       SetConsoleCtrlHandler (&ctrl_c_handler, FALSE);
 
       if (retval)
-	return ptid_t (current_event.dwProcessId, 0, retval);
+	return ptid_t (current_event.dwProcessId, retval, 0);
       else
 	{
 	  int detach = 0;
@@ -2892,8 +2892,8 @@
 std::string
 windows_nat_target::pid_to_str (ptid_t ptid)
 {
-  if (ptid.tid () != 0)
-    return string_printf ("Thread %d.0x%lx", ptid.pid (), ptid.tid ());
+  if (ptid.lwp () != 0)
+    return string_printf ("Thread %d.0x%lx", ptid.pid (), ptid.lwp ());
 
   return normal_pid_to_str (ptid);
 }
@@ -2978,7 +2978,7 @@
 {
   windows_thread_info *th;
 
-  th = thread_rec (ptid.tid (), 0);
+  th = thread_rec (ptid.lwp (), 0);
   if (th == NULL)
     return false;
 
@@ -2991,7 +2991,7 @@
 ptid_t
 windows_nat_target::get_ada_task_ptid (long lwp, long thread)
 {
-  return ptid_t (inferior_ptid.pid (), 0, lwp);
+  return ptid_t (inferior_ptid.pid (), lwp, 0);
 }
 
 /* Implementation of the to_thread_name method.  */
@@ -2999,7 +2999,7 @@
 const char *
 windows_nat_target::thread_name (struct thread_info *thr)
 {
-  return thread_rec (thr->ptid.tid (), 0)->name.get ();
+  return thread_rec (thr->ptid.lwp (), 0)->name.get ();
 }
 
 
@@ -3159,8 +3159,8 @@
 {
   int tid;
 
-  gdb_assert (ptid.tid () != 0);
-  tid = ptid.tid ();
+  gdb_assert (ptid.lwp () != 0);
+  tid = ptid.lwp ();
 
   return WaitForSingleObject (thread_rec (tid, FALSE)->h, 0) != WAIT_OBJECT_0;
 }
