--- orig5037/mysys/my_alloc.c	2007-03-05 11:21:13.000000000 -0800
+++ new5037/mysys/my_alloc.c	2009-04-30 11:05:24.000000000 -0700
@@ -21,6 +21,41 @@
 #undef EXTRA_DEBUG
 #define EXTRA_DEBUG
 
+#if defined(USE_VALGRIND)
+/* Please use Valgrind version 3.2 or later */
+#include <valgrind/memcheck.h>
+
+/* some macros definitions, pretty much same as in innobase/include/univ.i */
+#define VG_MEM_ALLOC(addr, size)   VALGRIND_MAKE_MEM_UNDEFINED(addr, size)
+
+/* Mark the free'd memory unusable */
+#define VG_TRASH_MEM(X) \
+    VALGRIND_MAKE_MEM_NOACCESS(((char*)(X) + ((X)->size-(X)->left)), (X)->left)
+
+#else
+
+#define VG_MEM_ALLOC(addr, size)
+#define VG_TRASH_MEM(X) 
+
+#endif /* USE_VALGRIND */
+
+/* Clobber the free'd memory */
+#ifndef DBUG_OFF
+#define SCRUB_MEM(X) \
+do { \
+  VG_MEM_ALLOC(((char*)(X) + ((X)->size-(X)->left)), (X)->left); \
+  bfill(((char*)(X) + ((X)->size-(X)->left)), (X)->left, 0x8f); \
+} while(0)
+#else
+#define SCRUB_MEM(X) 
+#endif /* DBUG_OFF */
+
+/* Clobber the free'd memory and mark it unusable */
+#define TRASH_MEM(X) \
+do { \
+  SCRUB_MEM(X); \
+  VG_TRASH_MEM(X); \
+} while (0)
 
 /*
   Initialize memory root
@@ -145,6 +180,7 @@
 {
 #if defined(HAVE_purify) && defined(EXTRA_DEBUG)
   reg1 USED_MEM *next;
+  gptr ret;
   DBUG_ENTER("alloc_root");
   DBUG_PRINT("enter",("root: 0x%lx", (long) mem_root));
 
@@ -157,12 +193,14 @@
       (*mem_root->error_handler)();
     DBUG_RETURN((gptr) 0);			/* purecov: inspected */
   }
+
   next->next= mem_root->used;
   next->size= Size;
+  next->left= Size-ALIGN_SIZE(sizeof(USED_MEM));
   mem_root->used= next;
-  DBUG_PRINT("exit",("ptr: 0x%lx", (long) (((char*) next)+
-                                           ALIGN_SIZE(sizeof(USED_MEM)))));
-  DBUG_RETURN((gptr) (((char*) next)+ALIGN_SIZE(sizeof(USED_MEM))));
+  ret= (gptr) (((char*) next)+ALIGN_SIZE(sizeof(USED_MEM)));
+  DBUG_PRINT("exit",("ptr: 0x%lx", (long) ret));
+  DBUG_RETURN(ret);
 #else
   uint get_size, block_size;
   gptr point;
@@ -217,6 +255,7 @@
     mem_root->first_block_usage= 0;
   }
   DBUG_PRINT("exit",("ptr: 0x%lx", (ulong) point));
+  VG_MEM_ALLOC(point, Size);
   DBUG_RETURN(point);
 #endif
 }
@@ -272,8 +311,6 @@
   DBUG_RETURN((gptr) start);
 }
 
-#define TRASH_MEM(X) TRASH(((char*)(X) + ((X)->size-(X)->left)), (X)->left)
-
 /* Mark all data in blocks free for reusage */
 
 static inline void mark_blocks_free(MEM_ROOT* root)
@@ -344,13 +381,19 @@
   {
     old=next; next= next->next ;
     if (old != root->pre_alloc)
+    {
+      SCRUB_MEM(old);
       my_free((gptr) old,MYF(0));
+    }
   }
   for (next=root->free ; next ;)
   {
     old=next; next= next->next;
     if (old != root->pre_alloc)
+    {
+      SCRUB_MEM(old);
       my_free((gptr) old,MYF(0));
+    }    
   }
   root->used=root->free=0;
   if (root->pre_alloc)