Error --unconstrained record or array type is not supported

I was trying to compile the VHDL code with generic (Widthositive:=
;

In Quartus, I got the following error.
Error (10427): VHDL aggregate error at GCD.vhd(49): OTHERS choice used
in aggregate for unconstrained record or array type is not supported

-----------------------------------------------------------------
library IEEE;
use IEEE.STD_Logic_1164.all, IEEE.Numeric_STD.all;
entity GCD is
generic (Widthositive:= ; ---I have also tried natural and
integer, but all failed.
port (Clock,Reset,Load: in std_logic;
A,B: in unsigned(Width-1 downto 0);
Done: out std_logic;
Y: out unsigned(Width-1 downto 0));
end entity GCD;
architecture RTL of GCD is
signal A_New,A_Hold,B_Hold: unsigned(Width-1 downto 0);
signal A_lessthan_B: std_logic;
begin
----------------------------------------------------
-- Load 2 input registers and ensure B_Hold < A_Hold
---------------------------------------------------
LOAD_SWAP: process (Clock)
begin
if rising_edge(Clock) then
if (Reset = '0') then
A_Hold <= (others => '0');
B_Hold <= (others => '0');
elsif (Load = '1') then
A_Hold <= A;
B_Hold <= B;
elsif (A_lessthan_B = '1') then
A_Hold <= B_Hold;
B_Hold <= A_New;
else A_Hold <= A_New;
end if;
end if;
end process LOAD_SWAP;

SUBTRACT_TEST: process (A_Hold, B_Hold)
begin
-------------------------------------------------------
-- Subtract B_Hold from A_Hold if A_Hold >= B_Hold
------------------------------------------------------
if (A_Hold >= B_Hold) then
A_lessthan_B <= '0';
A_New <= A_Hold - B_Hold;
else
A_lessthan_B <= '1';
A_New <= A_Hold;
end if;
-------------------------------------------------
-- Greatest common divisor found if B_Hold = 0
-------------------------------------------------
if (B_Hold = (others => '0')) then -- here is the error B_Hold =
(others => '0')
Done <= '1';
Y <= A_Hold;
else
Done <= '0';
Y <= (others => '0');
end if;
end process SUBTRACT_TEST;
end architecture RTL;
-------------------------------------------------------------------------------
I also googled some topic about it, is it true that when using
generics, B_Hold = (others => '0') OTHERS choice used in aggregate for
unconstrained record or array type is not supported?

Zheyu.Gao@googlemail.com

[joris]

Try this instead:

if (B_Hold = (B_Hold'range => '0'))

joris

> Zheyu....@googlemail.com wrote:
> > I was trying to compile the VHDL code with generic (Widthositive:=
> > ;
>
> > In Quartus, I got the following error.
> > Error (10427): VHDL aggregate error at GCD.vhd(49): OTHERS choice used
> > in aggregate for unconstrained record or array type is not supported
>
> <snip>
>
> > -----------------------------------------------------------------
> > library IEEE;
> > use IEEE.STD_Logic_1164.all, IEEE.Numeric_STD.all;
> > entity GCD is
> > generic (Widthositive:= ; ---I have also tried natural and
> > integer, but all failed.
> > port (Clock,Reset,Load: in std_logic;
> > * *A,B: * in unsigned(Width-1 downto 0);
> > * *Done: *out std_logic;
> > * *Y: * * out unsigned(Width-1 downto 0));
> > end entity GCD;
> > architecture RTL of GCD is
> > * *signal A_New,A_Hold,B_Hold: unsigned(Width-1 downto 0);
> > * *signal A_lessthan_B: std_logic;
> > begin
>
> <snip>
>
> > * *if (B_Hold = (others => '0')) then *-- here is the error B_Hold =
> > (others => '0')
> > -------------------------------------------------------------------------------
> > I also googled some topic about it, is it true that when using
> > generics, B_Hold = (others => '0') OTHERS choice used in aggregate for
> > unconstrained record or array type is not supported?
>


Since B_hold is unsigned, you can take advantage of the overloading
and compare to an integer:

if B_hold = 0 then

Cheers,
Jim
SynthWorks VHDL Training
http://www.synthworks.com

JimLewis