debugger fails to stop at breakpoint in plain c++ code

[prady]

Hi,

I am using Qt 4.8.1 in Win 7, and have not installed VS.

when I add a "Plain C++ project" in Qt creator and set a breakpoint, the debugger is not stopping at the breakpoint.
I set build and run settings in Debug mode. but when I start debugging the application runs successfully but failed to stop at breakpoint.

The code is very simple like...

#include <iostream>
 
using namespace std;
 
int main()
{
    cout << "Hello World!" << endl;
    return 0;
}

#include <iostream>

using namespace std;

int main()
{
    cout << "Hello World!" << endl;
    return 0;
}

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I set a breakpoint at 'cout' statement. but its not hitting the breakpoint.
what else I have to do to debug the application ?