Originally posted by: Nawel

Hello,

I'm trying to solve a MIP problem using Cplex 12.6.  I get an IloCplex Exception in a particular situation. I tried to reproduce the issue with the following simple code (attached in this post).

The excustion aborted with this message: 

Error :CPLEX Error  9023:  Unknown error code.

terminate called after throwing an instance of 'IloCplex::Exception' 

Aborted (core dumped)

Can you help me find out the source of the problem ?
 

To find the source of your problem you could run your program through a debugger and have it stop once an exception is thrown. That should point you to the offending line of code.

In general, you should wrap your program into a try/catch block like this:

try {
    // Your code here
    ...
}
catch (IloException &e) {
    std::cerr << e << std::endl;
    throw e;
}

This will print out the exception message before the program dies. In most cases the exception message gives a very good hint about what is going wrong.