AR# 16157


5.1i XST - "FATAL_ERROR: Xst:fctutil.c: 997:1.25 - Current result may be incorrect..."


Keywords: 5.1i, VHDL, Verilog, multiple, driver, RTL, view, fatal, error, XST

Urgency: Standard

General Description:
When I synthesize a design through XST, the following error message occurs:

"FATAL_ERROR:Xst:fctutil.c:997:1.25 - Current result may be incorrect, in FctTreeToLPTerm (remove complex constant from specification) Process will terminate. To resolve this error, please consult the Answers Database and other online resources at If you need further assistance, please open a WebCase by clicking on the 'WebCase' link at"


This error occurs when the "Generate RTL Schematic" switch is on and multiple driver errors occur in the design. To determine the source of the multiple driver error problem, turn off "Generate RTL Schematic" as follows:

1. Right-click the "Synthesize" process.
2. Select "Properties".
3. Under the "Synthesis Properties" tab, change "Generate RTL Schematic" from "Yes" to "No".
AR# 16157
Date 10/20/2005
Status Archive
Type General Article
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