--- old/src/hotspot/os_cpu/linux_x86/gc/z/zPhysicalMemoryBacking_linux_x86.hpp	2019-03-13 12:29:26.121270899 +0100
+++ new/src/hotspot/os_cpu/linux_x86/gc/z/zPhysicalMemoryBacking_linux_x86.hpp	2019-03-13 12:29:25.787260124 +0100
@@ -58,7 +58,9 @@
 
   void map(ZPhysicalMemory pmem, uintptr_t offset) const;
   void unmap(ZPhysicalMemory pmem, uintptr_t offset) const;
-  void flip(ZPhysicalMemory pmem, uintptr_t offset) const;
+
+  void debug_map(ZPhysicalMemory pmem, uintptr_t offset) const;
+  void debug_unmap(ZPhysicalMemory pmem, uintptr_t offset) const;
 };
 
 #endif // OS_CPU_LINUX_X86_GC_Z_ZPHYSICALMEMORYBACKING_LINUX_X86_HPP