diff --git a/gdbserver/ChangeLog b/gdbserver/ChangeLog
index 2b381455ed7..2abe0f1268c 100644
--- a/gdbserver/ChangeLog
+++ b/gdbserver/ChangeLog
@@ -1,3 +1,7 @@
+2020-04-15  Simon Marchi  <simon.marchi@polymtl.ca>
+
+	* win32-low.cc (get_child_debug_event): Fix format string warning.
+
 2020-04-13  Tom Tromey  <tom@tromey.com>
 
 	* server.h (gdb_fildes_t): Remove typedef.
diff --git a/gdbserver/win32-low.cc b/gdbserver/win32-low.cc
index e1226b4b0db..75305a4cfab 100644
--- a/gdbserver/win32-low.cc
+++ b/gdbserver/win32-low.cc
@@ -1457,7 +1457,7 @@ get_child_debug_event (DWORD *continue_status,
       /* Pending stop.  See the comment by the definition of
 	 "pending_stops" for details on why this is needed.  */
       OUTMSG2 (("get_windows_debug_event - "
-		"unexpected stop in 0x%x (expecting 0x%x)\n",
+		"unexpected stop in 0x%lx (expecting 0x%x)\n",
 		ptid.lwp (), desired_stop_thread_id));
       maybe_adjust_pc ();
       pending_stops.push_back ({(DWORD) ptid.lwp (), *ourstatus, current_event});