Re: What does -gnato do?

["Jeffrey R. Carter" <spam.not.jrcarter@acm.not.spam.org>]

Peter C. Chapin wrote:
> 
> with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;
> procedure Check is
>    X : Integer := Integer'Last;
> begin
>    X := X + 1;
>    Put(X);
> end Check;
> 
> When I build this program *without* the -gnato option I get the 
> following warning:
> 
> check.adb:6:11: warning: value not in range of type "Standard.Integer"
> check.adb:6:11: warning: "Constraint_Error" will be raised at run time

It's apparent that the compiler has calculated the result of the 
addition in order to issue this warning. It may then have replaced the 
assignment by "raise Constraint_Error;".

Make the value of X dynamic and see if -gnato makes a difference:

X : Integer := Integer'Value (Ada.Command_Line.Argument (1) );

-- 
Jeff Carter
"Sheriff murdered, crops burned, stores looted,
people stampeded, and cattle raped."
Blazing Saddles
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