Re: GNAT GPL 2012 bug of iterator?

[Martin <martin@thedowies.com>]

On Wednesday, June 27, 2012 7:43:19 AM UTC+1, kylix wrote:
> I try to compile the test code under GNAT GPL 2012, and it give a error message:
> gcc -c -O2 test.adb
> test.adb:42:13: invalid prefix in selected component "c"
> gnatmake: "test.adb" compilation error
> 
> It seems can't use list iterator in generic package.
> 
> Here are the test code:
> 
> pragma Ada_2012;
> with Ada.Text_IO;
> with Ada.Containers, Ada.Containers.Doubly_Linked_Lists;
> use Ada.Containers;
> procedure test is
> 
>    package Foo is
> 
>       type Rect_Type is tagged record
> 	 w, h, a : Integer := 0;
>       end record;
> 
>       procedure Calc (this : in out Rect_Type);
> 
>       type Rect_Ptr is access Rect_Type;
>    end Foo;
> 
>    package body Foo is
> 
>       procedure Calc (this : in out Rect_Type) is
>       begin
> 	 this.a := this.w * this.h;
>       end Calc;
> 
>    end Foo;
> 
> 
>    generic
>    package Generic_Pkg is
>       use Foo;
>       package Lists is new Doubly_Linked_Lists(Foo.Rect_Type);
> 
>       procedure Calc (list : in out Lists.List);
> 
>    end Generic_Pkg;
> 
>    package body Generic_Pkg is
> 
>       procedure Calc (list : in out Lists.List) is
>       begin
> 	 for c of list loop
> 	    c.Calc; -- if this code not in generic package, it works fine
> 	 end loop;
>       end;
>    end Generic_Pkg;
> 
>    package Rect is new Generic_Pkg;
> 
>    rs : Rect.Lists.List;
> 
> begin
>    for i in 1 .. 5 loop
>       rs.Append ((others => i));
>    end loop;
>    Rect.Calc(rs);
>    for c of rs loop
>       Ada.Text_IO.Put_Line (Integer'Image(c.a));
>    end loop;
> end test;

Same message in GNAT Pro 7.1.0 [actually GNAT Pro 7.1.0w (20120523-45)]

-- Martin