BUG in Ada compiler?

[rargyle@wsccs.UUCP (Bob Argyle)]

greetings Ada wizards, 

The following program on a VAX 8700 prints out:
"Hello, your program is exceptional!"
but if I change either 32767 to 32768, it runs fine: "Hello, World"
Two questions: 1. Am I overlooking something very basic?  Or, 
2.  Is the compiler here broken? Is _yours_?

with text_io; use text_io;
procedure bug is
   m:array (0..32767,0..32767) of character;
   begin
      m(0,8) := 'c';
      put("Hello, ");
      m(1,8) := 'c';
      put_line("World");
   exception
      when numeric_error | constraint_error => 
         put_line("numeric_error | constraint_error"); 
         -- must have same handler or compiler complains.
      when program_error => put_line("program_error");
      when storage_error => put_line("storage_error");
      when tasking_error => put_line("tasking_error");
      when data_error	 => put_line("data_error");
      when status_error	 => put_line("status_error");
      when mode_error	 => put_line("mode_error");
      when name_error	 => put_line("name_error");
      when use_error	 => put_line("use_error");
      when device_error	 => put_line("device_error");
      when end_error	 => put_line("end_error");
      when layout_error	 => put_line("layout_error");
      when others 	 => put_line("your program is exceptional!");
      -- no known named exception raised
   end bug;

-- 
bob argyle @ wsccs      void where prohibited.  int where not declared.
#ifndef disclaimer
	/*
#endif