[Cbc] integer overflow in CglGomory.cpp

[Tobias Stengel]

Hi,

I noticed an integer overflow in CglGomory.cpp / nearestRational(double, int) lines 445 and 446. That specific MIP is solved correctly, but I have no idea whether such an overflow can lead to wrong cuts that e.g. cut off the optimal solution. Anyway integer overflow is undefined behaviour in C/C++ and the returned fractional is not "near" the input...

2 parameter sets for nearestRational that lead to overflow can be found in the attached test program. Does anyone know how nearestRational works and how the overflow can be fixed properly?

Thanks

Tobias



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