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AR# 18494

6.2i XST - During incremental synthesis, XST does not generate a new top-level NGC file after changes to source files are made


Keywords: XST, synthesize, synthesis, resynthesize, resynthesis, incremental

Urgency: Standard

General Description:
XST does not regenerate a new top-level NGC file using incremental synthesis if the NGC file already exists. (This occurs when the top-level file is in Verilog.)


This problem has been fixed in the latest 6.2i Service Pack, available at:
The first service pack containing the fix is 6.2i Service Pack 1.

You can also work around this issue by using the RESYNTHESIZE constraint in the XCF to force the regeneration.

For more information on the RESYNTHESIZE constraint, please refer to the Constraints Guide.

For more information on how to use the XCF, please refer to the XST User Guide:
AR# 18494
Date Created 11/26/2003
Last Updated 07/18/2007
Status Archive
Type General Article