diff -r 9046db64ca39 -r cddef3bde924 src/hotspot/share/runtime/os.cpp
--- a/src/hotspot/share/runtime/os.cpp	Wed Sep 11 14:16:27 2019 +0200
+++ b/src/hotspot/share/runtime/os.cpp	Wed Sep 11 14:16:30 2019 +0200
@@ -796,7 +796,7 @@
 #endif
 }
 
-
+// handles NULL pointers
 void  os::free(void *memblock) {
   NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
 #ifdef ASSERT