ERROR: In process testbench.vhd:stim_proc Signal EXCEPTION

HI all,

For the following VHDL code, I am stuck with this error message.
This error is in procedure PrepareInput . Can anybody tell me what is the mistake I have done in that procedure.

ERROR: In process testbench.vhd:stim_proc
Signal EXCEPTION_ACCESS_VIOLATION received

***************
ARCHITECTURE behavior OF testbench IS


-- Clock period definitions
constant i_clk_period : time := 1us;

-- internal signal declaration....
type memory_0 is array (0 to IR*IC-1) of integer;
type memory_1 is array (0 to Cool of integer;
type memory_2 is array (0 to Cool of real;
type memory_3 is array (0 to IR*IC-1) of real;
type memory_4 is array (0 to 53) of std_logic_vector (7 downto 0);

signal pixelImage, thresh, RTL_output : memory_0;
signal dx, dy : memory_1;
signal gaussian, kernel, non : memory_2;
signal p, conv_in, ix, iy, ix2, iy2, ixiy : memory_3;
signal A_matrix, B_matrix, C_matrix, cornerness, non_max, conv_out : memory_3;
signal header_data : memory_4;
signal start_count: std_logic;
signal done: std_logic;
signal index : integer:= 0;


procedure PrepareInput is
variable inLIne: line;
variable c_buf: character;
variable int_text : integer:= 0;
type data_file_t is file of text;
-- file file_in : data_file_t open READ_MODE is "../data/input/lena_64_64.bmp";
file file_in : text open read_mode is "../data/input/lena_64_64.txt";
begin
report " Prepare Input is going on";
dx(0) <= -1; dy(0) <= -1;
dx(1) <= 0; dy(1) <= -1;
dx(2) <= 1; dy(2) <= -1;
dx(3) <= -1; dy(3) <= 0;
dx(4) <= 0; dy(4) <= 0;
dx(5) <= 1; dy(5) <= 0;
dx(6) <= -1; dy(6) <= 1;
dx(7) <= 0; dy(7) <= 1;
dx(Cool <= 1; dy(Cool <= 1;

-- Sigma = 1.4 ---g33
-- gaussian(0) <= 0.0924; gaussian(1) <= 0.1192; gaussian(2) <= 0.0924;
-- gaussian(3) <= 0.1192; gaussian(4) <= 0.1538; gaussian(5) <= 0.1192;
--gaussian(6) <= 0.0924; gaussian(7) <= 0.1192; gaussian(Cool <= 0.0924;

while(not endfile(file_in)) loop
report " entering loop";
readline(file_in, inLIne);
exit when endfile (file_in);
read(inLIne, int_text);
-- read(file_in, c_buf);
-- pixelImage(index+1) <=integer'value(s);
-- pixelImage(index+1) <=character'pos(c_buf);
-- pixelImage(index) <= int_text;
-- index <= index + 1;
end loop;
report " out of lopp";

file_close(file_in);

end PrepareInput;

begin

process
begin
PrepareInput; -- procedure calling
end process;

end;