Description

I get the following error in XST when targeting Virtex-6/Spartan-6 devices, but do not have any issues when I target older devices. why?

ERROR:HDLCompiler:69 - "<file>.vhd" Line xx:: <xyz> is not declared.

ERROR:HDLCompiler:461 - "<file>.vhd" Line xx:: If you are trying to directly instantiate a design entity, please use expanded name.

Example code:

library ieee;

use ieee.std_logic_1164.all;

entity subb_0007 is

port(in_port : in std_logic;

out_port: out std_logic);

end subb_0007;

architecture beh of subb_0007 is

begin

out_port <= in_port;

end;

-----------------------------------

library ieee;

use ieee.std_logic_1164.all;

entity ex_0007 is

port(in_port : in std_logic;

out_port: out std_logic);

end ex_0007;

architecture beh of ex_0007 is

begin

my_name : entity subb_0007 port map(in_port =>in_port,

out_port=>out_port);

end;

Solution

The above example attempts to use direct instantiation, but the subb_0007 entity is used without a library name. This is not a VHDL LRM compliant code. To solve the problem you have to use expanded name for the instantiations.

For example:- work.subb_0007 is used to fix the above code.

library ieee;

use ieee.std_logic_1164.all;

entity subb_0007 is

port(in_port : in std_logic;

out_port: out std_logic);

end subb_0007;

architecture beh of subb_0007 is

begin

out_port <= in_port;

end;

-----------------------------------

library ieee;

use ieee.std_logic_1164.all;

entity ex_0007 is

port(in_port : in std_logic;

out_port: out std_logic);

end ex_0007;

architecture beh of ex_0007 is

begin

my_name : entity work.subb_0007 port map(in_port =>in_port, -- Note: Error points here

out_port=>out_port);

end;

In 11.2 XST introduced a new VHDL/Verilog parser for Virtex-6 and Spartan-6 families. For more information on this change please refer (Xilinx Answer 32927)