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AR# 41727

13.1 XST - Using pre-compiled libraries fails when targeting Virtex-6, Spartan-6, and newer architectures


Using pre-compiled libraries in my VHDL files of a new project does not work correctly. This is very useful for code re-use across project.

Use XST property to set the location of the required library:

set -xsthdpini ".\hdl.ini"

This library is then referenced in the VHDL files as follows:

library mylib;
use mylib.lib.all;

For the most recent architectures using the new XST parser, this fails with errors as follows:

"ERROR:HDLCompiler:104 - "main.vhd" Line 4: Cannot find <lib> in library <mylib>. Please ensure that the library was compiled, and that a library and a use clause are present in the VHDL file.
Parsing entity <main>.
ERROR:HDLCompiler:854 - "main.vhd" Line 7: Unit <main> ignored due to previous errors.
Parsing architecture <default> of entity <main>."


This is aknown limitation with the new parser.

To work around this issue, the library files must be included in the current project and compiled again.

AR# 41727
Date Created 04/21/2011
Last Updated 12/15/2012
Status Active
Type General Article
  • ISE Design Suite - 12.4
  • ISE Design Suite - 13.1