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AR# 61548

Vivado Sysgen - When Logical block has output set to Boolean and "ERROR: [Synth 8-944] 0 definitions of operator "/=" match here" may occur


When I try to generate the Synthesized Checkpoint from the Vivado Sysgen Token or when Synthesizing the generated HDL Netlist or IP Catalog output from Sysgen I receive the following error:

ERROR: [Synth 8-944] 0 definitions of operator "/=" match here [F:/<path_to_test_model>/export_cast/Synthesized Checkpoint/logical_bool.srcs/sources_1/imports/sysgen/logical_bool_entity_declarations.vhd:62]

The line of code referred to is part of the Logical block code generated from Sysgen.

  unregy_3_1_convert <= (fully_2_1_bit /= "0");

Is this a known issue?

Is there any workaround?


This is a known issue and occurs when the Logical block has its output set to Boolean and the Sysgen language is set to VHDL.

There are two work-arounds at this time:

  1. Set the Sysgen language to Verilog.
  2. Change the output of the Logical block to UFIX_1_0 and then add the Convert block after the Logical block to change this UFIX_1_0 signal to a Boolean.

A request has been filed for this issue to be fixed in the next release.

AR# 61548
Date Created 07/18/2014
Last Updated 07/21/2014
Status Active
Type General Article
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