[Bug c++/30603] New: wrong results - when long long varaible is multiplied with big number

["jvn245 at yahoo dot com" <gcc-bugzilla at gcc dot gnu dot org>]

I am trying to check memory limit for my application. I am multiplying some
constant with argv[1]. I am getting correct results if my arg[1] is 5000 and
incorrect value if arg[1] is 6000. Infact it is returning samller value when I
multiply with 6000.
my code is as follows:
======================
#include <iostream>
#include <stdio.h>
using namespace std;

int main(int args, char **argv)
{
  int rowsetSize = atoi(argv[1]);
  const long long twoGB = 2560000000UL;  //2.5 GB
  const unsigned int recordLength = 30046;
  long long totalMemory = (long long) ( 50L * rowsetSize * recordLength ) ;
    {
      cout << "total Memory: " << totalMemory << " rowset size: " << rowsetSize
 << " record length: " << recordLength << endl;     
    }
    if ( totalMemory > twoGB )
    {
      cout <<  "program memory requirement exceeds 2.5GB, try again by
decreasing the transaction size." << endl;
    }


I compiled as 
gcc -lstdc++ -g -o limit1.exe limit1.cpp

output
=======
$ ./limit1.exe 6000
total Memory: 423865408 rowset size: 6000 record length: 30046
$ ./limit1.exe 5000
total Memory: 3216532704 rowset size: 5000 record length: 30046
program memory requirement exceeds 2.5GB, try again by decreasing the
transaction size.

my system specification:
=========================
$ uname -a
Linux BMC011 2.6.9-22.0.2.ELsmp #1 SMP Thu Jan 5 17:13:01 EST 2006 i686 i686
i386 GNU/Linux

thank
nirmala


-- 
           Summary: wrong results - when long long varaible is multiplied
                    with big number
           Product: gcc
           Version: 3.4.4
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jvn245 at yahoo dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30603