Re: GNAT GPL 2009 for Mac OS X (Snow Leopard)

[Jerry <lanceboyle@qwest.net>]

On Dec 22, 8:29 pm, "(see below)" <yaldni...@blueyonder.co.uk> wrote:
> On 22/12/2009 23:37, in article
> 96854a61-2032-49b1-a8b2-8a5aee181...@22g2000yqr.googlegroups.com, "sjw"
>
> <simon.j.wri...@mac.com> wrote:
> > Have just uploaded gnat-gpl-2009-i386-apple-darwin10.2.0-1.tar.bz2,
> > without the dependency; will remove the offending files after a day or
> > two.
>
> Unfortunately, it goes very badly wrong at -O1 optimization level on another
> example:
>
> --------------------------------------------------------------------------- -
> package test is
>    type i64 is mod 2**64;
>    for  i64'Size use 64;
>    subtype a_virtual_address is i64;
>    subtype an_offset is a_virtual_address;
>
>    function fetch_byte_from (
>          location : i64;
>          position : an_offset )
>    return i64;
> end test;
> --
> package body test is
>    type i08 is mod 2**8;
>    for  i08'Size use 8;
>    type an_i08_array is array (a_virtual_address range <>) of i08;
>    for  an_i08_array'Component_Size use i08'Size;
>    type an_i08_group is new an_i08_array (0..7);
>    for  an_i08_group'Size use i64'Size;
>    pragma Convention (C, an_i08_group);
>
>    function fetch_byte_from (
>          location : i64;
>          position : an_offset )
>    return i64 is
>       the_location_as_i08s : an_i08_group;
>       for the_location_as_i08s'Address use location'Address;
>       pragma Import (Ada, the_location_as_i08s);
>    begin
>       return i64(the_location_as_i08s
>                   ((position and 2#111#) xor 2#111#));
>    end fetch_byte_from;
> end test;
> --------------------------------------------------------------------------- -
>
> thus:
>
> +===========================GNAT BUG DETECTED==============================+
> | GPL 2009 (20090519) (i386-apple-darwin10.2.0) GCC error:                 |
> | in gnat_to_gnu_entity, at ada/gcc-interface/decl.c:312                   |
> | Error detected at test.adb:14:7                                          |
> ...
>
> This error message does not appear at -O3, but the generated object program
> is non-functional, although that may be for a different reason, of course.
>
> This code compiled and ran correctly under the Leopard compilers I was using
> until I stupidly installed SL.
>
> What on earth has happened for GNAT to regress so badly in the face of what
> is often described as a tidying-up and performance release of OS X?
>
> --
> Bill Findlay
> <surname><forename> chez blueyonder.co.uk

I thought OS X was officially supported by AdaCore. From the viewpoint
of a casual bystander, it looks like someone is asleep at the wheel.
This isn't support that I can believe in.

Jerry