While editing VHDL files I randomly get spammed with a bunch of errors like this:
null pointer

Each of the details shows the same error (null pointer). Once I clear these, it leaves the editor in an inconsistent state with a lot of valid text marked as errors. Closing and re-opening the file seems to be the only method of recovery. I'm able to reproduce this using a simple file, follow the directions in the comment at that line, it's actually pretty annoying when creating new entities:

library ieee;

use ieee.std_logic_1164.all;

use ieee.numeric_std.all;

 

entity test is

port (clk       : in    std_logic;
      reset     : in    std_logic;
      d         : in    std_logic;   --TRY DELETING THE "logic;"  using backspace starting at the ';' or even selecting and using delete
      q         : in    std_logic

);

end entity;

It appears that the error has some interaction with the semi-colon at the end of that line. The error only occurs when the semi-colon is missing (which is the case when you're typing in a new port for example), if the semi-colon is present then it's correctly underlined as an error when the word is not std_logic.