Does Quartus 20.1 std support VHDL 2008 vector aggregation?

I believe you are correct - Quartus Standard does not support aggregates for VHDL 2008 due to its limited language support. The following list is the closest I could find of VHDL 2008 features that Quartus Standard supports, prior to the release of Quartus Pro version:

https://www.intel.com/content/www/us/en/programmable/quartushelp/16.0/index.htm#hdl/vhdl/vhdl_list_2008_vhdl_support.htm

I have try to run below code (Fail in Standard but Pass in Pro):

library ieee;
use ieee.std_logic_1164.all;

entity Example is

 port (
  clk : in std_logic;
  reset : in std_logic;
  out_data : out std_logic_vector(7 downto 0)
 );

end entity Example;

architecture Behavioral of Example is
 signal signal_a : std_logic_vector(7 downto 0) := (others => '1');
begin

 process (clk, reset)
 begin
  if reset = '1' then
   -- reset the signal to the initial value
   signal_a <= (3 downto 0 => "0001", others => '1');
  elsif rising_edge(clk) then
   -- do some processing using the signal
   out_data <= signal_a;
  end if;
 end process;

end architecture Behavioral;

Best Regards,

Richard Tan

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