Re: Ada in Debian: transition to GCC 4.3 for Lenny

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

Tero Koskinen wrote:
> On Tue, 5 Feb 2008 02:03:49 -0800 (PST) Ludovic Brenta wrote:
> > As a consequence, I feel that
> > gnat-4.3 will be more stable and correct than gnat-4.2 (which is
> > already pretty good).
>
> I have been playing with gnat-4.3 on OpenBSD lately. Early January
> snapshots had some strange regression and "make bootstrap" took
> over 30 hours when it normally takes only about 2-3 hours on my computer.
> Fortunately, this was fixed in later snapshots and so far gnat-4.3
> has behaved nicely for me. For example, gnat-4.3 seems to be about
> 10%-20% faster than gnat-gpl-2007.

I know. This is http://gcc.gnu.org/PR34400 and I refrained from
uploading to Debian until it was fixed :)

> > In addition, it seems suitable for building the
> > latest versions of AWS and ASIS (but I'll report separately on that
> > when the time comes).
>
> I would like to know if you get ASIS working with gnat-4.3.

Sure, I'll let you know. The code base of gnat-4.3 seems close to GNAT
GPL 2007 so I'll try ASIS 2007 first. Failing that, I'll fall back on
ASIS 2006.

> I tried to compile gnat-asis-2007 using my customized gnat-4.3, but
> adabrowse and adacontrol started to give Program_Errors and
> Constrain_Errors, so I had to revert back to gnat-gpl-2007+gnat-asis-2007
> combination for ASIS. Those errors might be because of my own
> customizations, but I don't have a Linux computer around so I cannot
> verify where the problem is.
>
> -snip-
> Example errors:
>
> +===========================ASIS BUG DETECTED==============================+
> | ASIS 2.0.R for GNAT GPL 2007 (20070402)) PROGRAM_ERROR Inconsistent versions of GNAT and ASIS|

The root cause for this problem is that ASIS contains duplicate copies
of parts of GNAT - but, you giessed it, with different versions. ASIS
explicitly checks the value of GNATVSN.GNAT_Version_String and raises
this Program_Error if it finds a mismatch.

In Debian, this problem cannot arise because I have removed the root
cause for it. I build a library called libgnatvsn directly from the
GCC sources; then I remove the duplicate and inconsistent sources from
ASIS and build ASIS using libgnatvsn instead, and, of course, linking
dynamically.

The same applies to GPS which contains even more of GNAT's internal.
Specifically, in addition to the files in libgnatvsn, it contains an
out-of-date copy of the project manager. For this I build libgnatprj
from the GCC sources, remove the duplicates from GPS, and link
dynamically against both libgnatvsn and libgnatprj. Past versions of
GPS even contained an out-of-date copy of GtkAda which I also removed.

> +===========================ASIS BUG DETECTED==============================+
> | ASIS 2.0.R for GNAT GPL 2007 (20070402)) CONSTRAINT_ERROR table.adb:199 range check failed|
> | when processing A4G.Contt.SD.Read_and_Check_New (tree file /home/tkoskine/work/ahven/ahven-doubly_linked_list.adt)|

That one is different but may still be related to a version clash. If
I see it, I'll fix it.

--
Ludovic Brenta.