diff --git a/manifest b/manifest
index a4a5c34e91..71f5116089 100644
--- a/manifest
+++ b/manifest
@@ -1,28 +1,28 @@
-C :-)\s(CVS\s79)
-D 2000-06-08T11:25:01
+C remove\sall\smemory\sleaks\s(CVS\s80)
+D 2000-06-08T13:36:40
 F COPYRIGHT 74a8a6531a42e124df07ab5599aad63870fa0bd4
 F Makefile.in 17ba1ccf8d2d40c627796bba8f72952365d6d644
 F README 51f6a4e7408b34afa5bc1c0485f61b6a4efb6958
 F configure 00a5b5c82147a576fa6e82d7c1b0d55c321d6d2c x
 F configure.in 6ccfd5fc80517f7cfe605a7fc7e0f62d962a233c
 F doc/lemon.html e233a3e97a779c7a87e1bc4528c664a58e49dd47
-F src/build.c 5e3b6bab5604cd99019ea6d58f9166d879476991
+F src/build.c 925a785da2758269cb8773691e157ea5269178ba
 F src/dbbe.c 9b191b16ff01ec5bc0af436558501d07938ba4f0
 F src/dbbe.h a8a46f71238e0f09f3ec08fd9d1c8c7f4cdc49bf
 F src/delete.c c267b93f7ccb5493b677fa18201880267c699aa8
-F src/expr.c ab419c2f09529c8c518484b7f9af68b79e481064
+F src/expr.c 8c79de4d19081fe81765dac47bd496c32b606369
 F src/insert.c ac4edfff474589c00b2490f206317dc5822122e5
 F src/main.c e3297835b8e38ca726ac73f2c2bdb7cf08103197
-F src/parse.y bb2126c8313c111184b89af8675911dcb57f1dca
-F src/select.c d0b54f5f5a2bb6cd5aebc24c192dea4d4dbaeb84
+F src/parse.y e6c61f20620b4a331fecb5217eb556ac41aa441c
+F src/select.c b1ffe8e6a03540f690c3749c9c12257fca3463bc
 F src/shell.c 3f4afc39a36e4824e8aa262623fd03568874799e
 F src/sqlite.h 58da0a8590133777b741f9836beaef3d58f40268
-F src/sqliteInt.h 816c491f9896090dde03804fd3f60346456b99df
+F src/sqliteInt.h 0aac58ed2e9fe46f24411e2e012fe85cd3457129
 F src/tclsqlite.c 9f358618ae803bedf4fb96da5154fd45023bc1f7
-F src/tokenize.c 900af9479d0feaa76b0225680196aa81afec930a
+F src/tokenize.c cb9eacd12548ee1ae7089eb3177b38851d7f0a1f
 F src/update.c d8d90df714bac99c68446a0c49f3d957ca6fc3c8
-F src/util.c 33f9baa01e45394ef0cf85361a0e872987884315
-F src/vdbe.c 0ce44df13c97472686b376cc93cca5f40079878d
+F src/util.c 38e4bb5edf6fa92e677698c45785bf73c69b9e9f
+F src/vdbe.c 37f3b0824f90bfe3001dcf337bafb982f9d1b025
 F src/vdbe.h 8f79f57c66ce1030f6371ff067b326d627a52c6d
 F src/where.c c9b90e7672f4662a83ef9a27a193020d69fe034c
 F test/all.test 0950c135cab7e60c07bd745ccfad1476211e5bd7
@@ -43,12 +43,13 @@ F test/select5.test b6f8b6bef467764a3edaea4e7cb9b0eb8f02ccd8
 F test/sort.test d582086c4bb7df3fbf50aa72e69d7e235e9f8e31
 F test/subselect.test bf8b251a92fb091973c1c469ce499dc9648a41d5
 F test/table.test 85d6f410d127ec508c6640f02d7c40d218414e81
-F test/tester.tcl 44690d463c1dc83a4c76ccde07cc146a988600f6
+F test/tester.tcl 95b286791e6256bb6db0165f9342c70fff549a62
 F test/update.test 69459302ea75cafac1479e60b0e36efb88123c0e
 F test/vacuum.test 8becf5cfeb897108b35cdd996793e7f1df2f28fd
 F tool/gdbmdump.c 529e67c78d920606ba196326ea55b57b75fcc82b
 F tool/lemon.c 1f0e96515c12e9e413f5b8fdebc79ddcf18ddc9d
 F tool/lempar.c a1eec94d6eacc12332368660ec65f3b248853833
+F tool/memleak.awk a0a11dd84bf4582acc81c3c61271021ae49b3f15
 F tool/opNames.awk 2bd9071a138e4e2be13dc98fe066398a61219e1e
 F tool/opcodeDoc.awk b3a2a3d5d3075b8bd90b7afe24283efdd586659c
 F tool/renumberOps.awk 6d067177ad5f8d711b79577b462da9b3634bd0a9
@@ -56,7 +57,7 @@ F www/c_interface.tcl 9ac800854272db5fe439e07b7435b243a5422293
 F www/changes.tcl 04e66b4257589ff78a7e1de93e9dda4725fb03d6
 F www/index.tcl 52e29a4eeda8d59e91af43c61fef177c5f2ffd53
 F www/sqlite.tcl 2f933ce18cffd34a0a020a82435ab937137970fd
-P 923c14fe120c7d5470a18257659154c4f98226b7
-R 57bfb2e9c02ed1359339dbb2f56b538b
+P 305b043f4f71278d6d2c32e6e457f63efefae20d
+R 2e8cf1a074c330c6453a374880c3eab1
 U drh
-Z d5e2038c5fa3d3fb8e65d77ade627b18
+Z f0a43ffe3166fea312bf9330021c453e
diff --git a/manifest.uuid b/manifest.uuid
index 799644c392..58b0a76d00 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-305b043f4f71278d6d2c32e6e457f63efefae20d
\ No newline at end of file
+bf98cf82a73c54c4eced04994bb1a019844dfc03
\ No newline at end of file
diff --git a/src/build.c b/src/build.c
index ad6113e75b..692b61a418 100644
--- a/src/build.c
+++ b/src/build.c
@@ -33,7 +33,7 @@
 **     COPY
 **     VACUUM
 **
-** $Id: build.c,v 1.16 2000/06/07 23:51:50 drh Exp $
+** $Id: build.c,v 1.17 2000/06/08 13:36:40 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -191,6 +191,7 @@ void sqliteDeleteTable(sqlite *db, Table *pTable){
     pNext = pIndex->pNext;
     sqliteDeleteIndex(db, pIndex);
   }
+  sqliteFree(pTable->zName);
   sqliteFree(pTable->aCol);
   sqliteFree(pTable);
 }
@@ -202,8 +203,7 @@ void sqliteDeleteTable(sqlite *db, Table *pTable){
 ** be freed by the calling function.
 */
 char *sqliteTableNameFromToken(Token *pName){
-  char *zName = 0;
-  sqliteSetNString(&zName, pName->z, pName->n, 0);
+  char *zName = sqliteStrNDup(pName->z, pName->n);
   sqliteDequote(zName);
   return zName;
 }
diff --git a/src/expr.c b/src/expr.c
index 54840b07d8..a3200eb4d9 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -23,7 +23,7 @@
 *************************************************************************
 ** This file contains C code routines used for processing expressions
 **
-** $Id: expr.c,v 1.12 2000/06/08 11:25:01 drh Exp $
+** $Id: expr.c,v 1.13 2000/06/08 13:36:40 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -118,8 +118,7 @@ int sqliteExprResolveIds(Parse *pParse, IdList *pTabList, Expr *pExpr){
     case TK_ID: {
       int cnt = 0;   /* Number of matches */
       int i;         /* Loop counter */
-      char *z = 0;
-      sqliteSetNString(&z, pExpr->token.z, pExpr->token.n, 0);
+      char *z = sqliteStrNDup(pExpr->token.z, pExpr->token.n);
       for(i=0; i<pTabList->nId; i++){
         int j;
         Table *pTab = pTabList->a[i].pTab;
@@ -159,10 +158,8 @@ int sqliteExprResolveIds(Parse *pParse, IdList *pTabList, Expr *pExpr){
       pRight = pExpr->pRight;
       assert( pLeft && pLeft->op==TK_ID );
       assert( pRight && pRight->op==TK_ID );
-      zLeft = 0;
-      sqliteSetNString(&zLeft, pLeft->token.z, pLeft->token.n, 0);
-      zRight = 0;
-      sqliteSetNString(&zRight, pRight->token.z, pRight->token.n, 0);
+      zLeft = sqliteStrNDup(pLeft->token.z, pLeft->token.n);
+      zRight = sqliteStrNDup(pRight->token.z, pRight->token.n);
       for(i=0; i<pTabList->nId; i++){
         int j;
         char *zTab;
@@ -512,8 +509,23 @@ void sqliteExprCode(Parse *pParse, Expr *pExpr){
       sqliteVdbeAddOp(v, OP_AddImm, -1, 0, 0, 0);
       break;
     }
-    case TK_NOT:
     case TK_UMINUS: {
+      assert( pExpr->pLeft );
+      if( pExpr->pLeft->op==TK_INTEGER ){
+        int i = atoi(pExpr->pLeft->token.z);
+        sqliteVdbeAddOp(v, OP_Integer, -i, 0, 0, 0);
+        break;
+      }else if( pExpr->pLeft->op==TK_FLOAT ){
+        Token *p = &pExpr->pLeft->token;
+        char *z = sqliteMalloc( p->n + 2 );
+        sprintf(z, "-%.*s", p->n, p->z);
+        sqliteVdbeAddOp(v, OP_String, 0, 0, z, 0);
+        sqliteFree(z);
+        break;
+      }
+      /* Fall true into TK_NOT */
+    }
+    case TK_NOT: {
       sqliteExprCode(pParse, pExpr->pLeft);
       sqliteVdbeAddOp(v, op, 0, 0, 0, 0);
       break;
diff --git a/src/parse.y b/src/parse.y
index 864bce4cff..5b58983021 100644
--- a/src/parse.y
+++ b/src/parse.y
@@ -26,7 +26,7 @@
 ** the parser.  Lemon will also generate a header file containing
 ** numeric codes for all of the tokens.
 **
-** @(#) $Id: parse.y,v 1.16 2000/06/07 23:51:50 drh Exp $
+** @(#) $Id: parse.y,v 1.17 2000/06/08 13:36:40 drh Exp $
 */
 %token_prefix TK_
 %token_type {Token}
@@ -271,16 +271,14 @@ itemlist(A) ::= item(X).     {A = sqliteExprListAppend(0,X,0);}
 item(A) ::= INTEGER(X).      {A = sqliteExpr(TK_INTEGER, 0, 0, &X);}
 item(A) ::= PLUS INTEGER(X). {A = sqliteExpr(TK_INTEGER, 0, 0, &X);}
 item(A) ::= MINUS INTEGER(X). {
-  A = sqliteExpr(TK_INTEGER, 0, 0, 0);
-  A->token.z = 0;
-  sqliteSetNString(&A->token.z, "-", 1, X.z, X.n, 0);
+  A = sqliteExpr(TK_UMINUS, 0, 0, 0);
+  A->pLeft = sqliteExpr(TK_INTEGER, 0, 0, &X);
 }
 item(A) ::= FLOAT(X).        {A = sqliteExpr(TK_FLOAT, 0, 0, &X);}
 item(A) ::= PLUS FLOAT(X).   {A = sqliteExpr(TK_FLOAT, 0, 0, &X);}
 item(A) ::= MINUS FLOAT(X).  {
-  A = sqliteExpr(TK_FLOAT, 0, 0, 0);
-  A->token.z = 0;
-  sqliteSetNString(&A->token.z, "-", 1, X.z, X.n, 0);
+  A = sqliteExpr(TK_UMINUS, 0, 0, 0);
+  A->pLeft = sqliteExpr(TK_FLOAT, 0, 0, &X);
 }
 item(A) ::= STRING(X).       {A = sqliteExpr(TK_STRING, 0, 0, &X);}
 item(A) ::= NULL.            {A = sqliteExpr(TK_NULL, 0, 0, 0);}
diff --git a/src/select.c b/src/select.c
index 0aa76ff011..58b35ce1a7 100644
--- a/src/select.c
+++ b/src/select.c
@@ -24,7 +24,7 @@
 ** This file contains C code routines that are called by the parser
 ** to handle SELECT statements.
 **
-** $Id: select.c,v 1.21 2000/06/08 11:25:01 drh Exp $
+** $Id: select.c,v 1.22 2000/06/08 13:36:40 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -144,6 +144,7 @@ static int selectInnerLoop(
     }
     zSortOrder[pOrderBy->nExpr] = 0;
     sqliteVdbeAddOp(v, OP_SortMakeKey, pOrderBy->nExpr, 0, zSortOrder, 0);
+    sqliteFree(zSortOrder);
     sqliteVdbeAddOp(v, OP_SortPut, 0, 0, 0, 0);
   }else 
 
@@ -378,12 +379,12 @@ static int matchOrderbyToColumn(
     for(j=0; j<pEList->nExpr; j++){
       if( pEList->a[i].zName && (pE->op==TK_ID || pE->op==TK_STRING) ){
         char *zName = pEList->a[i].zName;
-        char *zLabel = 0;
-        sqliteSetNString(&zLabel, pE->token.z, pE->token.n, 0);
+        char *zLabel = sqliteStrNDup(pE->token.z, pE->token.n);
         sqliteDequote(zLabel);
         if( sqliteStrICmp(zName, zLabel)==0 ){ 
           match = 1; 
         }
+        sqliteFree(zLabel);
       }
       if( match==0 && sqliteExprCompare(pE, pEList->a[i].pExpr) ){
         match = 1;
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index a4530ce79b..eec9e4b861 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -23,7 +23,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.22 2000/06/07 23:51:51 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.23 2000/06/08 13:36:40 drh Exp $
 */
 #include "sqlite.h"
 #include "dbbe.h"
@@ -40,11 +40,23 @@
 # define sqliteMalloc(X)    sqliteMalloc_(X,__FILE__,__LINE__)
 # define sqliteFree(X)      sqliteFree_(X,__FILE__,__LINE__)
 # define sqliteRealloc(X,Y) sqliteRealloc_(X,Y,__FILE__,__LINE__)
+# define sqliteStrDup(X)    sqliteStrDup_(X,__FILE__,__LINE__)
+# define sqliteStrNDup(X,Y) sqliteStrNDup_(X,Y,__FILE__,__LINE__)
   void sqliteStrRealloc(char**);
 #else
 # define sqliteStrRealloc(X)
 #endif
 
+/*
+** The following global variables are used for testing and debugging
+** only.  Thy only work if MEMORY_DEBUG is defined.
+*/
+#ifdef MEMORY_DEBUG
+int sqlite_nMalloc;         /* Number of sqliteMalloc() calls */
+int sqlite_nFree;           /* Number of sqliteFree() calls */
+int sqlite_iMallocFail;     /* Fail sqliteMalloc() after this many calls */
+#endif
+
 /*
 ** The number of entries in the in-memory hash table holding the
 ** schema.
@@ -306,10 +318,14 @@ int sqliteSortCompare(const char *, const char *);
   void *sqliteMalloc_(int,char*,int);
   void sqliteFree_(void*,char*,int);
   void *sqliteRealloc_(void*,int,char*,int);
+  char *sqliteStrDup_(const char*,char*,int);
+  char *sqliteStrNDup_(const char*, int,char*,int);
 #else
   void *sqliteMalloc(int);
   void sqliteFree(void*);
   void *sqliteRealloc(void*,int);
+  char *sqliteStrDup(const char*);
+  char *sqliteStrNDup(const char*, int);
 #endif
 int sqliteGetToken(const char*, int *);
 void sqliteSetString(char **, const char *, ...);
diff --git a/src/tokenize.c b/src/tokenize.c
index ef2726a4f5..b0f197efae 100644
--- a/src/tokenize.c
+++ b/src/tokenize.c
@@ -27,7 +27,7 @@
 ** individual tokens and sends those tokens one-by-one over to the
 ** parser for analysis.
 **
-** $Id: tokenize.c,v 1.9 2000/06/07 02:04:23 drh Exp $
+** $Id: tokenize.c,v 1.10 2000/06/08 13:36:40 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -328,6 +328,7 @@ int sqliteRunParser(Parse *pParse, char *zSql, char **pzErrMsg){
         ** special SQL comments.  Check for the special comments
         ** here and take approriate action if found.
         */
+#ifndef NDEBUG
         char *z = pParse->sLastToken.z;
         if( sqliteStrNICmp(z,"--parser-trace-on--",19)==0 ){
           trace = stderr;
@@ -339,7 +340,26 @@ int sqliteRunParser(Parse *pParse, char *zSql, char **pzErrMsg){
           pParse->db->flags |= SQLITE_VdbeTrace;
         }else if( sqliteStrNICmp(z,"--vdbe-trace-off--", 18)==0 ){
           pParse->db->flags &= ~SQLITE_VdbeTrace;
+#ifdef MEMORY_DEBUG
+        }else if( sqliteStrNICmp(z,"--malloc-file=",14)==0 ){
+          sqlite_iMallocFail = atoi(&z[14]);
+        }else if( sqliteStrNICmp(z,"--malloc-stats--", 16)==0 ){
+          if( pParse->xCallback ){
+            static char *azName[4] = {"malloc", "free", "to_fail", 0 };
+            char *azArg[4];
+            char zVal[3][30];
+            sprintf(zVal[0],"%d", sqlite_nMalloc);
+            sprintf(zVal[1],"%d", sqlite_nFree);
+            sprintf(zVal[2],"%d", sqlite_iMallocFail);
+            azArg[0] = zVal[0];
+            azArg[1] = zVal[1];
+            azArg[2] = zVal[2];
+            azArg[3] = 0;
+            pParse->xCallback(pParse->pArg, 3, azArg, azName);
+          }
+#endif
         }
+#endif
         break;
       }
       case TK_ILLEGAL:
@@ -349,31 +369,36 @@ int sqliteRunParser(Parse *pParse, char *zSql, char **pzErrMsg){
         break;
       default:
         sqliteParser(pEngine, tokenType, pParse->sLastToken, pParse);
-        if( pParse->zErrMsg ){
+        if( pParse->zErrMsg && pParse->sErrToken.z ){
           sqliteSetNString(pzErrMsg, "near \"", -1, 
              pParse->sErrToken.z, pParse->sErrToken.n,
              "\": ", -1,
              pParse->zErrMsg, -1,
              0);
           nErr++;
+          sqliteFree(pParse->zErrMsg);
+          pParse->zErrMsg = 0;
         }
         break;
     }
   }
   if( nErr==0 ){
     sqliteParser(pEngine, 0, pParse->sLastToken, pParse);
-    if( pParse->zErrMsg ){
+    if( pParse->zErrMsg && pParse->sErrToken.z ){
        sqliteSetNString(pzErrMsg, "near \"", -1, 
           pParse->sErrToken.z, pParse->sErrToken.n,
           "\": ", -1,
           pParse->zErrMsg, -1,
           0);
        nErr++;
+       sqliteFree(pParse->zErrMsg);
+       pParse->zErrMsg = 0;
     }
   }
   sqliteParserFree(pEngine, free);
   if( pParse->zErrMsg ){
     if( pzErrMsg ){
+      sqliteFree(*pzErrMsg);
       *pzErrMsg = pParse->zErrMsg;
     }else{
       sqliteFree(pParse->zErrMsg);
diff --git a/src/util.c b/src/util.c
index b3e0d7760c..5d53beb98d 100644
--- a/src/util.c
+++ b/src/util.c
@@ -26,7 +26,7 @@
 ** This file contains functions for allocating memory, comparing
 ** strings, and stuff like that.
 **
-** $Id: util.c,v 1.11 2000/06/05 16:01:39 drh Exp $
+** $Id: util.c,v 1.12 2000/06/08 13:36:41 drh Exp $
 */
 #include "sqliteInt.h"
 #include <stdarg.h>
@@ -43,6 +43,11 @@ void *sqliteMalloc_(int n, char *zFile, int line){
   void *p;
   int *pi;
   int k;
+  sqlite_nMalloc++;
+  if( sqlite_iMallocFail>=0 ){
+    sqlite_iMallocFail--;
+    if( sqlite_iMallocFail==0 ) return 0;
+  }
   k = (n+sizeof(int)-1)/sizeof(int);
   pi = malloc( (3+k)*sizeof(int));
   if( pi==0 ) return 0;
@@ -65,6 +70,7 @@ void sqliteFree_(void *p, char *zFile, int line){
     int *pi, k, n;
     pi = p;
     pi -= 2;
+    sqlite_nFree++;
     if( pi[0]!=0xdead1122 ){
       fprintf(stderr,"Low-end memory corruption at 0x%x\n", (int)p);
       return;
@@ -123,7 +129,7 @@ void *sqliteRealloc_(void *oldP, int n, char *zFile, int line){
   memset(oldPi, 0, (oldK+3)*sizeof(int));
   free(oldPi);
 #if MEMORY_DEBUG>1
-  fprintf(stderr,"realloc %d->%d bytes at 0x%x->0x%x at %s:%d\n", oldN, n,
+  fprintf(stderr,"realloc %d to %d bytes at 0x%x to 0x%x at %s:%d\n", oldN, n,
     (int)oldP, (int)p, zFile, line);
 #endif
   return p;
@@ -142,6 +148,24 @@ void sqliteStrRealloc(char **pz){
   *pz = zNew;
 }
 
+/*
+** Make a copy of a string in memory obtained from sqliteMalloc()
+*/
+char *sqliteStrDup_(const char *z, char *zFile, int line){
+  char *zNew = sqliteMalloc_(strlen(z)+1, zFile, line);
+  if( zNew ) strcpy(zNew, z);
+  return zNew;
+}
+char *sqliteStrNDup_(const char *z, int n, char *zFile, int line){
+  char *zNew = sqliteMalloc_(n+1, zFile, line);
+  if( zNew ){
+    memcpy(zNew, z, n);
+    zNew[n] = 0;
+  }
+  return zNew;
+}
+
+
 #else  /* !defined(MEMORY_DEBUG) */
 /*
 ** Allocate new memory and set it to zero.  Return NULL if
@@ -178,6 +202,23 @@ void *sqliteRealloc(void *p, int n){
   }
   return realloc(p, n);
 }
+
+/*
+** Make a copy of a string in memory obtained from sqliteMalloc()
+*/
+char *sqliteStrDup(const char *z){
+  char *zNew = sqliteMalloc(strlen(z)+1);
+  if( zNew ) strcpy(zNew, z);
+  return zNew;
+}
+char *sqliteStrNDup(const char *z, int n){
+  char *zNew = sqliteMalloc(n+1);
+  if( zNew ){
+    memcpy(zNew, z, n);
+    zNew[n] = 0;
+  }
+  return zNew;
+}
 #endif /* MEMORY_DEBUG */
 
 /*
@@ -210,6 +251,11 @@ void sqliteSetString(char **pz, const char *zFirst, ...){
     zResult += strlen(zResult);
   }
   va_end(ap);
+#ifdef MEMORY_DEBUG
+#if MEMORY_DEBUG>1
+  fprintf(stderr,"string at 0x%x is %s\n", (int)*pz, *pz);
+#endif
+#endif
 }
 
 /*
@@ -243,6 +289,11 @@ void sqliteSetNString(char **pz, ...){
     zResult += n;
   }
   *zResult = 0;
+#ifdef MEMORY_DEBUG
+#if MEMORY_DEBUG>1
+  fprintf(stderr,"string at 0x%x is %s\n", (int)*pz, *pz);
+#endif
+#endif
   va_end(ap);
 }
 
diff --git a/src/vdbe.c b/src/vdbe.c
index 1f99a61754..6fbb5bae98 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -41,7 +41,7 @@
 ** But other routines are also provided to help in building up
 ** a program instruction by instruction.
 **
-** $Id: vdbe.c,v 1.27 2000/06/07 15:39:04 drh Exp $
+** $Id: vdbe.c,v 1.28 2000/06/08 13:36:41 drh Exp $
 */
 #include "sqliteInt.h"
 #include <unistd.h>
@@ -254,7 +254,7 @@ int sqliteVdbeAddOp(Vdbe *p, int op, int p1, int p2, const char *p3, int lbl){
   }
   p->aOp[i].p2 = p2;
   if( p3 && p3[0] ){
-    sqliteSetString(&p->aOp[i].p3, p3, 0);
+    p->aOp[i].p3 = sqliteStrDup(p3);
   }else{
     p->aOp[i].p3 = 0;
   }
@@ -523,8 +523,7 @@ static int hardStringify(Vdbe *p, int i){
     p->aStack[i].flags |= STK_Str;
     return 0;
   }
-  p->zStack[i] = 0;
-  sqliteSetString(&p->zStack[i], zBuf, 0);
+  p->zStack[i] = sqliteStrDup(zBuf);
   if( p->zStack[i]==0 ) return 1;
   p->aStack[i].n = strlen(p->zStack[i])+1;
   p->aStack[i].flags |= STK_Str|STK_Dyn;
@@ -846,7 +845,6 @@ static Sorter *Merge(Sorter *pLeft, Sorter *pRight){
   return sHead.pNext;
 }
 
-
 /*
 ** Execute the program in the VDBE.
 **
@@ -886,11 +884,17 @@ int sqliteVdbeExec(
   /* if( pzErrMsg ){ *pzErrMsg = 0; } */
   for(pc=0; rc==SQLITE_OK && pc<p->nOp && pc>=0; pc++){
     pOp = &p->aOp[pc];
+
+    /* Only allow tracing if NDEBUG is not defined.
+    */
+#ifndef NDEBUG
     if( p->trace ){
       fprintf(p->trace,"%4d %-12s %4d %4d %s\n",
         pc, zOpName[pOp->opcode], pOp->p1, pOp->p2,
            pOp->p3 ? pOp->p3 : "");
     }
+#endif
+
     switch( pOp->opcode ){
       /* Opcode:  Goto P2 * *
       **
@@ -1893,7 +1897,6 @@ int sqliteVdbeExec(
       */
       case OP_KeyAsData: {
         int i = pOp->p1;
-        VdbeTable *pTab;
         if( i>=0 && i<p->nTable && p->aTab[i].pTable!=0 ){
           p->aTab[i].keyAsData = pOp->p2;
         }
@@ -2683,6 +2686,7 @@ int sqliteVdbeExec(
         int i = pOp->p1;
         int tos = p->tos;
         Mem *pMem;
+        char *zOld;
         if( tos<0 ) goto not_enough_stack;
         if( i>=p->nMem ){
           int nOld = p->nMem;
@@ -2695,14 +2699,16 @@ int sqliteVdbeExec(
         }
         pMem = &p->aMem[i];
         if( pMem->s.flags & STK_Dyn ){
-          sqliteFree(pMem->z);
+          zOld = pMem->z;
+        }else{
+          zOld = 0;
         }
         pMem->s = p->aStack[tos];
         if( pMem->s.flags & STK_Str ){
-          pMem->z = 0;
-          sqliteSetString(&pMem->z, p->zStack[tos], 0);
+          pMem->z = sqliteStrNDup(p->zStack[tos], pMem->s.n);
           pMem->s.flags |= STK_Dyn;
         }
+        if( zOld ) sqliteFree(zOld);
         PopStack(p, 1);
         break;
       }
@@ -2824,6 +2830,12 @@ int sqliteVdbeExec(
         if( pFocus==0 ) goto no_mem;
         if( i>=0 && i<p->agg.nMem ){
           Mem *pMem = &pFocus->aMem[i];
+          char *zOld;
+          if( pMem->s.flags & STK_Dyn ){
+            zOld = pMem->z;
+          }else{
+            zOld = 0;
+          }
           pMem->s = p->aStack[tos];
           if( pMem->s.flags & STK_Str ){
             pMem->z = sqliteMalloc( p->aStack[tos].n );
@@ -2831,6 +2843,7 @@ int sqliteVdbeExec(
             memcpy(pMem->z, p->zStack[tos], pMem->s.n);
             pMem->s.flags |= STK_Str|STK_Dyn;
           }
+          if( zOld ) sqliteFree(zOld);
         }
         PopStack(p, 1);
         break;
@@ -2973,6 +2986,13 @@ int sqliteVdbeExec(
         break;
       }
     }
+
+    /* The following code adds nothing to the actual functionality
+    ** of the program.  It is only here for testing and debugging.
+    ** On the other hand, it does burn CPU cycles every time through
+    ** the evaluator loop.  So we can leave it out when NDEBUG is defined.
+    */
+#ifndef NDEBUG
     if( pc<-1 || pc>=p->nOp ){
       sqliteSetString(pzErrMsg, "jump destination out of range", 0);
       rc = SQLITE_INTERNAL;
@@ -2999,6 +3019,7 @@ int sqliteVdbeExec(
       }
       fprintf(p->trace,"\n");
     }
+#endif
   }
 
 cleanup:
diff --git a/test/tester.tcl b/test/tester.tcl
index eb18a46ce1..cf132bf6da 100644
--- a/test/tester.tcl
+++ b/test/tester.tcl
@@ -23,7 +23,7 @@
 # This file implements some common TCL routines used for regression
 # testing the SQLite library
 #
-# $Id: tester.tcl,v 1.4 2000/05/31 17:59:27 drh Exp $
+# $Id: tester.tcl,v 1.5 2000/06/08 13:36:41 drh Exp $
 
 # Create a test database
 #
@@ -74,6 +74,7 @@ proc do_test {name cmd expected} {
 #
 proc finish_test {} {
   global nTest nErr
+  catch {db close}
   puts "$nErr errors out of $nTest tests"
   exit $nErr
 }
diff --git a/tool/memleak.awk b/tool/memleak.awk
new file mode 100644
index 0000000000..ca3366cf0d
--- /dev/null
+++ b/tool/memleak.awk
@@ -0,0 +1,25 @@
+#
+# This script looks for memory leaks by analyzing the output of "sqlite" 
+# when compiled with the MEMORY_DEBUG=2 option.
+#
+/^malloc / {
+  mem[$5] = $0
+}
+/^realloc / {
+  mem[$7] = "";
+  mem[$9] = $0
+}
+/^free / {
+  mem[$5] = "";
+}
+/^string at / {
+  addr = $3
+  sub("string at " addr " is ","")
+  str[addr] = $0
+}
+END {
+  for(addr in mem){
+    if( mem[addr]=="" ) continue
+    print mem[addr], str[addr]
+  }
+}