7.2.1.1 Merge User SDC file(s) with existing timing constraints

Select Merge User SDC file(s) with existing timing constraints to preserve all existing timing constraints that you have entered using either the constraints editor or in a previously imported SDC file.

If you import new SDC files and you have this checkbox selected, the software merges the existing constraints and the constraints from the new SDC files. In case of a conflict, the new constraints have priority over the existing constraints.

This option is ON by default. When this option is OFF, all the existing timing constraints are replaced by the constraints in the newly imported SDC files.