Re: Bug in GNAT GPL 2006?

[Per Sandberg <per.sandberg@bredband.net>]

Well it is fixed in the latest version (GNATPro 6.0.1).
/Per

(see below) wrote:
> On 22/2/07 02:14, in article
> 1172110443.971020.58150@v33g2000cwv.googlegroups.com, "Adam Beneschan"
> <adam@irvine.com> wrote:
> 
>> On Feb 21, 12:19 pm, "Randy Brukardt" <r...@rrsoftware.com> wrote:
>>> Bill Findlay writes:
>>>> Using GNAT GPL 2006 (20060522-34) I get warning messages
>>>> like the following when using extended return statements:
>>>>     function is_empty (the_table : a_safe_table) return Boolean is
>>>>     begin
>>>>        return result : Boolean do
>>>>               |
>>>>>>> warning: variable "result" is assigned but never read
>>>>           lock_table;
>>>>              result := is_empty(a_basic_table(the_table));
>>>>           unlock_table;
>>>>        end return;
>>>>     end is_empty;
>>>> I'm inclined to assume that this is a compiler bug, but can
>>>> anyone more knowledgeable about Ada 200[57] confirm this?
>>> Sure looks like a (harmless) compiler bug to me. It's hard to imagine why
>>> you would be required to read the result of a function before returning it.
>> Looks to me like the compiler is (incorrectly) pretending it's a
>> normal variable.  If you had declared "result : Boolean" before the
>> "begin", and then assigned it but never used it, I can imagine the
>> compiler being suspicious that something was perhaps mistyped
>> somewhere, and displaying a warning.  Just a very understandable
>> implementation bug.
> 
> Yes, I think so. 
> Extraordinarily, the example given in the Ada 2005 RM has this property.
> 
> Unfortunately, it is not the only extended return bug in GNAT GPL 2006.
> 
> Obtaining the value of a defining identifier from a call to another
> (inlined) function having itself an extended return also fails to compile;
> giving a nonsensical message at the point of call of the latter.
>