Index: /trunk/src/VBox/Additions/common/VBoxService/VBoxServicePageSharing.cpp
===================================================================
--- /trunk/src/VBox/Additions/common/VBoxService/VBoxServicePageSharing.cpp	(revision 29639)
+++ /trunk/src/VBox/Additions/common/VBoxService/VBoxServicePageSharing.cpp	(revision 29640)
@@ -22,4 +22,5 @@
 #include <iprt/assert.h>
 #include <iprt/avl.h>
+#include <iprt/asm.h>
 #include <iprt/mem.h>
 #include <iprt/stream.h>
@@ -157,5 +158,5 @@
                     {
                         /* Try to trick the optimizer to leave the page touching code in place. */
-                        dummy += *(char *)pRegion;
+                        ASMProbeReadByte(pRegion);
                         pRegion += PAGE_SIZE;
                     }