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AR# 34751

11.x XST - Constants from undeclared packages being used during parsing


I have two constants with the same name declared in two different VHDL package files. In a third source file, I use the first package file, but not the second, and reference the constant.

It appears that the value for the constant is being pulled from the second package file, which is not used in the source file. Therefore, it appears that the names of constants in package files are in at least some cases more global than they should be.

How can I resolve this issue so the appropriate constant is used in my entity?


This issue has been found in XST for devices older than Virtex-6 / Spartan-6 FPGA. This issue does not exist in XST for Virtex-6 / Spartan-6 FPGA.

To work around this issue in XST for Virtex-6 FPGA and older devices, rename the constants so they have a unique name.

AR# 34751
Date Created 03/15/2010
Last Updated 12/15/2012
Status Active
Type General Article