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Note: Xilinx has dropped 32-bit support for version 2015.1 (or later). If you are building on a 32-bit Linux kernel, you will need to use 2014.4 (or earlier).
Note: We are only supporting "incremental compile" for version 2015.3 (or later) <http://www.xilinx.com/video/hardware/incremental-compile-updates-for-2015_3.html>
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