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AR# 42257

13.3 PlanAhead - "WARNING:ConstraintSystem:56;..." An invalid component set invalidates entire constraint

Description

When evaluating and applying constraints from a User Constraints Format (UCF) file, if a component set is invalid, the entire constraint is ignored or invalidated even though there are other valid components set in the constraint.

For example, the following constraint is entered in "my_top.ucf":

MEGRP EVERYTHING = FFS LATCHES PADS BRAMS MULTS;

The Time Group "EVERYTHING" is not created because BRAMS is an invalid keyword.

If the design is run through ISE implementation tools, the NGDBuild report (*.bld) will contain a warning similar to the following:

WARNING:ConstraintSystem:56 - Constraint <TIMEGRP EVERYTHING = FFS LATCHES PADS
BRAMS MULTS;> [my_top.ucf(1)]: Unable to find an active 'TNM' or 'TimeGrp' constraint named 'BRAMS'."

Solution

This behavior represents a difference between the PlanAhead tool and Project Navigator flows in handling of constraints.

Through Project Navigator, only the incorrect constraint group is ignored.

Through the PlanAhead tool, the incorrect constraint group invalidates the entire constraint.

To avoid this issue in PlanAhead 13.3, correct the constraint so that it only contains valid groups.

The issue is resolved in PlanAhead 13.4.
AR# 42257
Date Created 05/20/2011
Last Updated 05/19/2012
Status Active
Type Known Issues
Tools
  • PlanAhead - 11.1
  • PlanAhead - 12.1
  • PlanAhead - 13.1