--- a/src/hotspot/os/aix/os_aix.cpp	Tue Aug 20 10:46:23 2019 +0200
+++ b/src/hotspot/os/aix/os_aix.cpp	Tue Aug 20 10:11:53 2019 +0100
@@ -4338,3 +4338,7 @@
   time_t t2 = get_mtime(file2);
   return t1 - t2;
 }
+
+bool os::supports_map_sync() {
+  return false;
+}