Fix a vdbe stack leak that could occur where one side of a WHERE clause inequality evaluated to SQL null. (CVS 4045)

FossilOrigin-Name: 17152bf1a268e130f0c43046bb438b617a747ff5

src/where.c

@@ -16,7 +16,7 @@
 ** so is applicable.  Because this module is responsible for selecting
 ** indices, you might also think of this module as the "query optimizer".
 **
-** $Id: where.c,v 1.249 2007/05/29 12:11:30 danielk1977 Exp $
+** $Id: where.c,v 1.250 2007/06/02 07:54:38 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 
@@ -2414,7 +2414,7 @@ WhereInfo *sqlite3WhereBegin(
         pX = pTerm->pExpr;
         assert( (pTerm->flags & TERM_CODED)==0 );
         sqlite3ExprCode(pParse, pX->pRight);
-        sqlite3VdbeAddOp(v, OP_IsNull, -(nEq+1), nxt);
+        sqlite3VdbeAddOp(v, OP_IsNull, -(nEq*2+1), nxt);
         topEq = pTerm->eOperator & (WO_LE|WO_GE);
         disableTerm(pLevel, pTerm);
         testOp = OP_IdxGE;