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AR# 34459

ISE 10.1.3 NGDBuild - Previous constraints showing up that have been removed


I am receiving warnings similar to the following:

WARNING:NgdBuild:1011 - The constraint <TIMESPEC TS_i1_i3_clk0_buf = PERIOD
"i1_i3_clk0_buf" TS_i01_int...> is overridden by the constraint <TIMESPEC
TS_i1_i3_clk0_buf = PERIOD "i1_i3_clk0_buf" TS_i01_int...>.

There are no duplicate constraints in any of my source files.

Where are these extra constraint coming from? 

This does not occur immediately a project cleanup.


This is due to residual constraints being left in the Constraints Database. 

These are left because of a problem with the timestamp checking, which is performed when the '-nt' option is set to timestamp. 

To work around this, set the '-nt' option to on so that the database will always be rebuilt. 

The '-nt' option is called the Netlist Translation Type.

This issue is fixed in the 11.1 ISE release.
AR# 34459
Date 01/13/2015
Status Active
Type General Article
  • ISE - 10.1
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