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AR# 60892

Vivado Synthesis - Undefined or undeclared attributes are ignored without any message


Undefined or undeclared attributes are ignored silently without any error or warning.

Below is an example code which demonstrates this issue.
architecture RTL of top is
    --attribute RLOC : string;
    attribute RLOC of LUT1_inst1 : label is "X0Y0";

    --attribute FOO : string;
    attribute FOO of LUT1_inst0 : label is "bar";


This is a known issue for Vivado Synthesis 2014.4 and older versions.
This has been fixed in Vivado 2015.1.

Vivado Synthesis now returns the following error on undeclared attributes.

ERROR: [Synth 8-1031] RLOC is not declared
ERROR: [Synth 8-1031] FOO is not declared

AR# 60892
Date Created 05/30/2014
Last Updated 12/15/2012
Status Active
Type Known Issues
  • Vivado Design Suite - 2014.1
  • Vivado Design Suite - 2014.2
  • Vivado Design Suite - 2013.4
  • Vivado Design Suite - 2013.3