Backport SQLite memcmp patch.

third_party/sqlite/src/src/expr.c

 /*
 ** 2001 September 15
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
 **
 **    May you do good and not evil.
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
@@ skipping 560 matching lines @@
     }
     if( i>pParse->nVar ){
       pParse->nVar = (int)i;
     }
   }else{
     /* Wildcards like ":aaa", "$aaa" or "@aaa".  Reuse the same variable
     ** number as the prior appearance of the same name, or if the name
     ** has never appeared before, reuse the same variable number
     */
     int i;
-    u32 n;
-    n = sqlite3Strlen30(z);
     for(i=0; i<pParse->nVarExpr; i++){
       Expr *pE = pParse->apVarExpr[i];
       assert( pE!=0 );
-      if( memcmp(pE->u.zToken, z, n)==0 && pE->u.zToken[n]==0 ){
+      if( strcmp(pE->u.zToken, z)==0 ){
         pExpr->iColumn = pE->iColumn;
         break;
       }
     }
     if( i>=pParse->nVarExpr ){
       pExpr->iColumn = (ynVar)(++pParse->nVar);
       if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
         pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
         pParse->apVarExpr =
             sqlite3DbReallocOrFree(
@@ skipping 3151 matching lines @@
   }
   return i;
 }
 void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){
   sqlite3ExprCacheRemove(pParse, iReg, nReg);
   if( nReg>pParse->nRangeReg ){
     pParse->nRangeReg = nReg;
     pParse->iRangeReg = iReg;
   }
 }