描述

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

"FATAL_ERROR:Timing:bastwoffsetpref.c:679:1.160.14.3.10.1 - 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?

解决方案

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.