Fix calls to std-library functions
Fix calls to std-library functions

On Windows this was giving compile errors.

Contributes to issue CURA-3238.

Ultimaker/CuraEngine,ROBO3D/CuraEngine,alephobjects/CuraEngine,ROBO3D/CuraEngine,alephobjects/CuraEngine,Ultimaker/CuraEngine,ROBO3D/CuraEngine,alephobjects/CuraEngine