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AR# 43271

Vivado HLS/AutoESL - RTL Implementation results in "@E [IMPL-4] 'autoimpl' failed: 'xtclsh' cannot be found. Please check your PATH variable."


RTL Implementation results in the following error:

@E [IMPL-4] 'autoimpl' failed: 'xtclsh' cannot be found. Please check your PATH variable.


To perform RTL implementation, AutoESL must invoke Xilinx ISE tools. Therefore, the Xilinx ISE tools path must be known; two ways to achieve this are explained below.

First, update the ".bat" file that invokes AutoESL. This can be performed with the following:

  1. Right-click on the shortcut in the Windows Start Menu to start the AutoESL GUI or command prompt, and select Properties.
  2. Prepend the ISE path to Target field; typically "C:\Xilinx\xilinx_version_number\ISE_DS\settings64.bat" for Win 64-bits OS, or "settings32.bat" for Win 32-bits OS.
  3. Finally, the Target field looks like "C\Xilinx\14.6\ISE_DS\settings64.bat C:\Xilinx\Vivado_HLS\2013.2\bin\vivado_hls.bat"

Alternatively, make sure the PATH environment variable points to Xilinx implementation tools.

For Windows, use the following commands (note that setx will make the environment variable stick):

  1. set XILINX=C:\Xilinx\xilinx_version_number\ISE_DS
  2. set PATH=%PATH%;%XILINX%\bin\nt
  3. [Optional] setx XILINX %XILINX%
  4. [Optional] setx PATH %PATH%

Linked Answer Records

Master Answer Records

Answer Number Answer Title Version Found Version Resolved
47429 Xilinx Vivado HLS Solution Center - Top Issues N/A N/A

Associated Answer Records

AR# 43271
Date Created 01/17/2012
Last Updated 11/07/2013
Status Active
Type General Article
  • Vivado Design Suite
  • Vivado Design Suite - 2013.2