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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Compiler checking of String lengths during assignment (Newbie
 Question)
Date: Fri, 16 Jan 2015 07:28:58 +0000
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Date: 2015-01-16T07:28:58+00:00
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Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org> writes:

> On 01/15/2015 02:18 PM, Simon Wright wrote:
>> 
>> As I think I've said before, with the same compiler (on Mac OS X, but
>> I'd be _very_ surprised if that made a difference) I get warnings on
>> all three lines.
>
> You don't have the code the OP compiled, since he didn't post
> it. There's no telling what may appear between "begin" and the lines
> in question in that code.  As Duff showed, a null procedure call is
> enough to eliminate the warning on the line using I.

It was Adam, not Bob.

Adam showed that

   procedure Main is
      Head : String (1..5) := "XXX_N";
      i : Positive;
      Line : String := "12312312312312312";
      procedure Nothing is null;
   begin
      i := 2;
      Nothing;                   -- <<<<< prevents the 3rd warning 
      Head := "123";
      Head := Line(1 .. 2);
      Head := Line(i+2 .. i+4);
   end Main;

and, while I agree with you that the OP should have posted a compilable
example that demonstrated the problem, the posted code had nothing
between the assignment to i and the assignments to Head.