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AR# 41521

13.1 PlanAhead - Constraints are ignored if there are syntax errors in the ".ucf" file


A user makes some changes to the ".ucf" file in the PlanAhead tool and in the process accidentally introduces syntactical errors in the ".ucf" file:

Example: NET "my_clk" LOC = "AA25;

Notice that it is missing an ending double quote for the site.

The PlanAhead tool ignores the constraints during implementation and does not indicate that it has been ignored.

When an impl run is launched the new ".ucf" file (Top.ucf) that gets copied into the impl run directory is missing this loc constraint.


The TCL console in the PlanAhead tool does show the following warning:

"CRITCAL WARNING : [Designutils-31] Unrecognized Symbol ;"

However, there are no errors or warnings that come up explicitly. The warning in the TCL console can easily be missed and is not intuitive.

In the PlanAhead 13.2 tool, a pop-up message has been added to make it obvious that there is a syntax error in the constraints file.
AR# 41521
Date Created 03/29/2011
Last Updated 07/06/2011
Status Active
Type Known Issues
  • PlanAhead - 13.2