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AR# 32460

11.1 Timing Known Issue - "FATAL_ERROR:Timing:bastwoffsetpref.c:679: - Clock arrival time not found"


When I have an OFFSET OUT constraint with the RISING or FALLING keywords, the following error occurs: 


"FATAL_ERROR:Timing:bastwoffsetpref.c:679: - Clock arrival time 

not found for your_clk. Process will terminate. For 

technical support on this issue, please open a WebCase with this project 

attached at http://www.xilinx.com/support."

How do I work around this issue?


This error can occur when MAP removes one of the clocks, or if the clock contains a TIG constraint. To work around this issue, remove the RISING and FALLING keywords. 


This is a known issue and is scheduled to be fixed in the next major release of the software.

AR# 32460
Date Created 04/10/2009
Last Updated 05/21/2014
Status Archive
Type General Article