diff -urpN gdb-7.12.1.orig/gdb/event-loop.h gdb-7.12.1/gdb/event-loop.h
--- gdb-7.12.1.orig/gdb/event-loop.h	2017-01-21 05:46:46.000000000 -0800
+++ gdb-7.12.1/gdb/event-loop.h	2019-03-14 11:55:56.280325742 -0700
@@ -66,6 +66,8 @@
    infinite loop.
 
    Corollary tasks are the creation and deletion of event sources.  */
+#ifndef _EVENT_LOOP_H_
+#define _EVENT_LOOP_H_
 
 typedef void *gdb_client_data;
 struct async_signal_handler;
@@ -127,3 +129,5 @@ extern void mark_async_event_handler (st
 extern void clear_async_event_handler (struct async_event_handler *handler);
 
 extern void initialize_async_signal_handlers (void);
+
+#endif