some questions on installing Ada on Linux

some questions on installing Ada on Linux

[Nasser M. Abbasi]

some basic questions. Goggling these is giving me hard so
I thought I ask here.

What is the correct way to install Ada on Linux these days?
I am on Linux mint 17.

1) Should one install GNAT on Linux by downloading tar files from
http://libre.adacore.com  (GPL 2014 edition) or use

   sudo apt-get install gnat-4.8

2) Will the sudo installation install all the stuff listed at
libre.adacore.com? including GPS editor and all the other
packages?

3) Which is more recent, gnat-4.8 or GPL 2014 edition?

4) When I go to http://libre.adacore.com/download/configurations
is there a way to tell it to check everything for download,
without one having to spend 1 hr clicking on the check-box
for each item? I do not see "select all"

It is really confusing having Ada/GNAT in 2 different places.
Why not have one place to install Ada from so it is less
confusing to users?

--Nasser

Re: some questions on installing Ada on Linux

[Simon Clubley]

On 2014-07-04, Nasser M. Abbasi <nma@12000.org> wrote:
>
> some basic questions. Goggling these is giving me hard so
> I thought I ask here.
>
> What is the correct way to install Ada on Linux these days?
> I am on Linux mint 17.
>
> 1) Should one install GNAT on Linux by downloading tar files from
> http://libre.adacore.com  (GPL 2014 edition) or use
>
>    sudo apt-get install gnat-4.8
>
> 2) Will the sudo installation install all the stuff listed at
> libre.adacore.com? including GPS editor and all the other
> packages?
>
> 3) Which is more recent, gnat-4.8 or GPL 2014 edition?
>
> 4) When I go to http://libre.adacore.com/download/configurations
> is there a way to tell it to check everything for download,
> without one having to spend 1 hr clicking on the check-box
> for each item? I do not see "select all"
>
> It is really confusing having Ada/GNAT in 2 different places.
> Why not have one place to install Ada from so it is less
> confusing to users?
>

I'll let someone who installs the pre-packaged toolchains answer your
other questions (I'm RedHat based and just build a new gcc/binutils
toolchain from the FSF source when the need arises) but the core problem
is that there are two distinct branches of the GNAT sources which cannot
be merged due to licence conflicts.

The FSF branch is the main gcc toolchain branch (C, C++, Ada, Fortran,
etc) which is present in all non-Ada installations and whose licence
allows you to create closed source commercial applications with it.
When a non-Ada person talks about "gcc" without identifying a specific
branch that's almost certainly the branch they are talking about.

In addition, AdaCore have their own version of this toolchain with
various Ada enhancements present in it (I don't know the details).
However, the public version of this AdaCore specific version of the
toolchain is strict GPL only which means you cannot create closed
source applications with it.

And yes, you are correct, it's probably all very confusing to a
newcomer to Ada to have multiple toolchains with incompatible licences
and it is just another barrier in the way of people trying out Ada.

I work with the FSF branch only because of it's additional freedoms
and because this branch is also the basis (for example) for Ada
language application support in RTEMS.

Simon.

-- 
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world

Re: some questions on installing Ada on Linux

[Dan'l Miller]

On Friday, July 4, 2014 7:22:37 AM UTC-5, Simon Clubley wrote:
> > What is the correct way to install Ada on Linux these days?
> ...
> > 1) Should one install GNAT on Linux by downloading tar files from
> > http://libre.adacore.com  (GPL 2014 edition)

Do this only if:
1) the entirety of each executable containing your Ada work and all of its supporting libraries are licensed under GPL; or
2) throwaway work, such as replicating a bug; or
3) trying out AdaCore's version before paying the over-$10,000-per-seat license.

> > or use:  sudo apt-get install gnat-4.8

Do this (or analogue on various distributions of Linux) for all other cases.  For example, I install GCC 4.9 from http://FinkProject.org for my MacOSX development.

> > 2) Will the sudo installation install all the stuff listed at
> > libre.adacore.com?

  No.  None of it exactly as supplied by AdaCore.  Some AdaCore libraries are licensed as GPL only, which is useful only in executables entirely licensed as GPL.  For this reason, the GPL-only libraries from AdaCore (i.e., dual-licensed GPL and over-$10,000 per seat) are generally not distributed in the open-source community.

> including GPS editor and all the other packages?

  No.  GPS is not distribute as source code publicly.  I am unclear whether source code to GPS is included in the over-$10,000-per-seat license for GNAT Pro.

> > 3) Which is more recent, gnat-4.8 or GPL 2014 edition?

The answer is:  it depends on which portion of GCC you are talking about.  As I understand it (2nd hand), generally, AdaCore uses an older back-end for its latest GPL & Pro editions.  So if you want the most recent back-end to all of GCC including to GNAT, then FSF GCC 4.9 is currently the most-recent version of the back-end.  But FSF uses a merge of its historical codebase plus an annual snapshot of GCC-GNAT source code that AdaCore is obligated by the GPL to make available.  So there is a natural lag time from AdaCore's release of 1) GNAT Pro versions versus 2) when the annual snapshot occurs to form a now FSF GCC release, such as 4.9.  As I understand it, FSF GNAT front-end lags behind GNAT Pro front-end approximately 1 year, or perhaps a year plus a fraction of a year.  So if you want the most-recent GNAT front-end for Ada, then GNAT Pro is very current (with multiple releases throughout the year) or GNAT GPL edition is 2nd best, being current on the day of its release and then getting stale throughout the year until the next GPL Edition version.

> > 4) When I go to http://libre.adacore.com/download/configurations
> > is there a way to tell it to check everything for download,
> > without one having to spend 1 hr clicking on the check-box
> > for each item? I do not see "select all"

  No, that would be yet another benefit of prepackaged FSF GCC (including GNAT) over AdaCore GPL Edition.

> > It is really confusing having Ada/GNAT in 2 different places.

  It is not done for reducing confusion.  The AdaCore repository is done for AdaCore to have a way to fund itself (which is better than the alternative:  no revenue).  The FSF repository is done for legal reasons as FSF is the ultimate owner of the rights to copy the GNAT compiler within GCC, not AdaCore.

> > Why not have one place to install Ada from so it is less
> > confusing to users?

  The solution that I foresee long-term would be for a community outside of AdaCore to become strong enough to support FSF GNAT well.  I suspect that means that eventually at least one other corporation other than AdaCore would need to donate some of its employees' time to maintenance & expansion of FSF GNAT, analogous to Red Hat and IBM and Canonical and so forth donating some of their time to maintenance & expansion of the Linux kernel.

> I'll let someone who installs the pre-packaged toolchains answer your
> other questions (I'm RedHat based and just build a new gcc/binutils
> toolchain from the FSF source when the need arises) but the core problem
> is that there are two distinct branches of the GNAT sources which cannot
> be merged due to licence conflicts.

  Is this actually factually correct?  I was of the understanding that they are substantially merged approximately once per year.  What obstructs a wholesale merge is the fact that AdaCore's GNAT lags behind 2 or 3 versions from the latest stable back-end.  FSF merges the vast majority of AdaCore's evolution of GNAT that does not conflict with changes in the back-end.  It is bit-rot, not legalese, that naturally causes 2 source bases for GNAT.  The relationship is symbiotic:  FSF depends on AdaCore for most of the evolution of the Ada front-end, whereas AdaCore depends on FSF for most of the evolution of the back-end.  AdaCore merges in a newer (but still lagging) back-end version approximately once per year to AdaCore's state-of-the-art front-end.  Separately, FSF merges in a newer (but still lagging) GNAT front-end version approximately once per year to FSF's state-of-the-art back-end.

Re: some questions on installing Ada on Linux

[Simon Wright]

"Dan'l Miller" <optikos@verizon.net> writes:

> On Friday, July 4, 2014 7:22:37 AM UTC-5, Simon Clubley wrote:
>> > What is the correct way to install Ada on Linux these days?
>> ...
>> > 1) Should one install GNAT on Linux by downloading tar files from
>> > http://libre.adacore.com  (GPL 2014 edition)
>
> Do this only if:
> 1) the entirety of each executable containing your Ada work and all of
> its supporting libraries are licensed under GPL; or

.. if you intend to distribute executables under the GPL.

> 2) throwaway work, such as replicating a bug; or
> 3) trying out AdaCore's version before paying the
> over-$10,000-per-seat license.

.. if paying for support is possible, you should contact AdaCore for ean
eval, since the prime benefit is access to support.

>> > or use:  sudo apt-get install gnat-4.8
>
> Do this (or analogue on various distributions of Linux) for all other
> cases.  For example, I install GCC 4.9 from http://FinkProject.org for
> my MacOSX development.

.. and I build GCC with various AdaCore libraries, released at
SourceForge. Of course this means I have to be careful about the GPL
aspects (as you do with the equivalent Debian packages). (I've never
been comfortable with fink or homebrew).

>> > 2) Will the sudo installation install all the stuff listed at
>> > libre.adacore.com?

There are several extra GNAT-related packages on Debian, eg
asis-programs.

>   No.  None of it exactly as supplied by AdaCore.  Some AdaCore
> libraries are licensed as GPL only, which is useful only in
> executables entirely licensed as GPL.  For this reason, the GPL-only
> libraries from AdaCore (i.e., dual-licensed GPL and over-$10,000 per
> seat) are generally not distributed in the open-source community.

If you look at GNAT GPL library source you will see some blank lines
after the standard GPL header; these are where the runtime exception,
which is embedded in the code provided to AdaCore supported customers
and in the FSF version, has been stripped out (I imagine there's an
automated script to do this in the release process).

>> including GPS editor and all the other packages?
>
>   No.  GPS is not distribute as source code publicly.  I am unclear
> whether source code to GPS is included in the over-$10,000-per-seat
> license for GNAT Pro.

Source code to GPS is distributed as part of GNAT GPL. But unless you
plan to distribute executables based on GPS source I don't see why you
need worry about its license; it's a development tool (cf Emacs). And it
requires a *lot* of external libraries. Just use the GPL distribution
for your system!

Actually, I suspect there's a Debian package .. yes, gnat-gps.

>> > 4) When I go to http://libre.adacore.com/download/configurations
>> > is there a way to tell it to check everything for download,
>> > without one having to spend 1 hr clicking on the check-box
>> > for each item? I do not see "select all"

You must click very slowly!

Re: some questions on installing Ada on Linux

[Simon Clubley]

On 2014-07-04, Dan'l Miller <optikos@verizon.net> wrote:
> On Friday, July 4, 2014 7:22:37 AM UTC-5, Simon Clubley wrote:
>
>> > It is really confusing having Ada/GNAT in 2 different places.
>
>   It is not done for reducing confusion.  The AdaCore repository is done for
> AdaCore to have a way to fund itself (which is better than the alternative:  no
> revenue).  The FSF repository is done for legal reasons as FSF is the ultimate
> owner of the rights to copy the GNAT compiler within GCC, not AdaCore.
>

Are you sure about that ? If the FSF has had a copyright assignment for
the GNAT compiler from AdaCore, then surely it's only for the FSF branch
of the gcc code. Please see below for my reasoning.

>
>> I'll let someone who installs the pre-packaged toolchains answer your
>> other questions (I'm RedHat based and just build a new gcc/binutils
>> toolchain from the FSF source when the need arises) but the core problem
>> is that there are two distinct branches of the GNAT sources which cannot
>> be merged due to licence conflicts.
>
>   Is this actually factually correct?

As I understand it, yes. If I am wrong about this, I would appreciate
being corrected as this can be a bit subtle in areas.

A third party cannot take the AdaCore GPL sources, import them into
FSF GCC and then distribute the combined sources under the terms of
the GMGPL.

However, AdaCore, as the owner of the code in question, can choose, if
it wishes, to add code to the FSF GCC codebase under more permissive
GMGPL terms and then assign the rights to that copy of the added code
to the FSF (if AdaCore indeed does do that).

However, as I understand it, in the absence of any contracts/agreements
granting additional rights to the customer, all AdaCore has to legally
do to satisfy the GPL is to release it's source code, under the pure GPL,
to the customers who purchase it's products or download the
binaries from AdaCore's website.

There's no requirement, unless it's part of some additional non-GPL
contract, to release any source code under the GMGPL unless AdaCore
choose to do so.

Therefore, as I understand it, AdaCore could stop contributing code
to the FSF gcc branch if it chooses, provided it makes the source code
for the binaries it actually supplies to customers available under the
GPL.

>  I was of the understanding that they
> are substantially merged approximately once per year.  What obstructs a
> wholesale merge is the fact that AdaCore's GNAT lags behind 2 or 3 versions
> from the latest stable back-end.  FSF merges the vast majority of AdaCore's
> evolution of GNAT that does not conflict with changes in the back-end.  It is
> bit-rot, not legalese, that naturally causes 2 source bases for GNAT.  The
> relationship is symbiotic:  FSF depends on AdaCore for most of the evolution of
> the Ada front-end, whereas AdaCore depends on FSF for most of the evolution of
> the back-end.  AdaCore merges in a newer (but still lagging) back-end version
> approximately once per year to AdaCore's state-of-the-art front-end. 
> Separately, FSF merges in a newer (but still lagging) GNAT front-end version
> approximately once per year to FSF's state-of-the-art back-end.

Unless there's some contract I am unaware of, there's nothing to
stop AdaCore saying that future releases to the FSF gcc codebase are
done under the terms of the pure GPL.

They have already done this once with another product. GtkAda used to
have a GMGPL style licence up to around GtkAda 2.4, but the public
version of GtkAda was converted (overnight) to a pure GPL licence.
Existing releases of GtkAda stayed under the GMGPL; new releases were
under the pure GPL.

And once again, if I am wrong about this, please feel free to correct
me. :-)

Simon.

PS: I have a polite request. Would it be possible for you to break up
your paragraphs please ? They come across as a monolithic block of text
which can be hard to read.

Thanks.

-- 
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world

Re: some questions on installing Ada on Linux

[Ludovic Brenta]

"Nasser M. Abbasi" <nma@12000.org> writes:
> some basic questions. Goggling these is giving me hard so
> I thought I ask here.
>
> What is the correct way to install Ada on Linux these days?
> I am on Linux mint 17.
>
> 1) Should one install GNAT on Linux by downloading tar files from
> http://libre.adacore.com  (GPL 2014 edition) or use
>
>   sudo apt-get install gnat-4.8

gnat-4.8 is an experimental version of the compiler that will not be
maintained and has been removed from Debian.  Your use of a derivative
cuts you off from both the stable branch of Debian, which uses gnat-4.6
and provides many precompiled libraries for it, and from the unstable
and testing branches, which are in the process of switching to gnat-4.9.

Therefore, if you don't want to use Debian, you should use GNAT GPL
Edtition.  The downside is that you will have to recompile any and all
libraries that you use in your programs (only the compiler and GPS are
precompiled).

> 2) Will the sudo installation install all the stuff listed at
> libre.adacore.com? including GPS editor and all the other packages?

On Debian, yes.  On Mint and other derivatives, probably not if they
carry only gnat-4.8.

> 3) Which is more recent, gnat-4.8 or GPL 2014 edition?

See http://people.debian.org/~lbrenta/debian-ada-policy.html for full
details; in particular the section 2.3.4 "FSF Releases".

> 4) When I go to http://libre.adacore.com/download/configurations
> is there a way to tell it to check everything for download,
> without one having to spend 1 hr clicking on the check-box
> for each item? I do not see "select all"
>
> It is really confusing having Ada/GNAT in 2 different places.  Why not
> have one place to install Ada from so it is less confusing to users?

The confusion will disappear if you read the introduction to Debian
Policy for Ada :)

-- 
Ludovic Brenta.

Re: some questions on installing Ada on Linux

[Simon Clubley]

On 2014-07-04, Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> wrote:
>
> However, AdaCore, as the owner of the code in question, can choose, if
> it wishes, to add code to the FSF GCC codebase under more permissive
> GMGPL terms and then assign the rights to that copy of the added code
> to the FSF (if AdaCore indeed does do that).
>

That's the copyright assignment I meant by the latter bit. I know AdaCore
does import some of it's code into the FSF GCC codebase.

Simon.

-- 
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world

Re: some questions on installing Ada on Linux

[Ludovic Brenta]

Simon Clubley writes on comp.lang.ada:
> Therefore, as I understand it, AdaCore could stop contributing code to
> the FSF gcc branch if it chooses, provided it makes the source code
> for the binaries it actually supplies to customers available under the
> GPL.

Yes, that is correct, AFAIU, but IANAL.

You must actually make a strong distinction between the compiler and the
libraries.  The compiler is and has always been pure GPL; that does not
matter to users of the compiler as long as they don't link the compiler
into their executables.

As far as libraries are concerned, you have to distinguish between
libgnat and the other libraries (such as GtkAda, XML/Ada, etc.).
libgnat from the FSF is licensed under GPL version 3 or later with
Runtime Library Exception, just like libstdc++.  In contrast, libgnat
from GNAT GPL is pure GPL i.e. no Runtime Library Exception.  (The
"GMGPL" license disappeared long ago; see the timeline in the Debian
Policy for Ada).

The sources for libgnat are distributed together with the compiler
(gnat), so are available from the FSF.  The other libraries are
distributed separately and are not available from the FSF.  They are
available from libre.adacore.com in source only form and they are also
available from several distributions in source and binary (precompiled)
forms.

Paying customers receive the Runtime Library Exception on all libraries
but not on the compiler or on GPS, AFAICT, but again that doesn't matter
since they don't incorporate the compiler or GPS into their software
(and, in fact, few of them even distribute their software to anyone, so
the redistribution terms of the license matter very little to them).

>> I was of the understanding that they are substantially merged
>> approximately once per year.  What obstructs a wholesale merge is the
>> fact that AdaCore's GNAT lags behind 2 or 3 versions from the latest
>> stable back-end.  FSF merges the vast majority of AdaCore's evolution
>> of GNAT that does not conflict with changes in the back-end.  It is
>> bit-rot, not legalese, that naturally causes 2 source bases for GNAT.
>> The relationship is symbiotic: FSF depends on AdaCore for most of the
>> evolution of the Ada front-end, whereas AdaCore depends on FSF for
>> most of the evolution of the back-end.  AdaCore merges in a newer
>> (but still lagging) back-end version approximately once per year to
>> AdaCore's state-of-the-art front-end.  Separately, FSF merges in a
>> newer (but still lagging) GNAT front-end version approximately once
>> per year to FSF's state-of-the-art back-end.

The once-per-year merges have long been banned by the FSF.  Nowadays,
AdaCore merge their changes in small chunks, almost daily, and obey the
GCC development schedule [1].

[1] https://gcc.gnu.org/develop.html

Looking at the bottom of that page: right now GCC 4.10 is in Stage 1, so
AdaCore are busy merging almost every day from GNAT Pro into the future
GCC 4.10.  If you want examples, look for emails tagged "[Ada]" on
https://gcc.gnu.org/ml/gcc-patches/2014-06/.

Again, please read the Debian Policy for Ada :)

> Unless there's some contract I am unaware of, there's nothing to stop
> AdaCore saying that future releases to the FSF gcc codebase are done
> under the terms of the pure GPL.

Yes, the FSF can stop AdaCore because the FSF owns the copyright on GNAT
and libgnat, so only the FSF gets to decide on the licensing terms.

> They have already done this once with another product. GtkAda used to
> have a GMGPL style licence up to around GtkAda 2.4, but the public
> version of GtkAda was converted (overnight) to a pure GPL licence.
> Existing releases of GtkAda stayed under the GMGPL; new releases were
> under the pure GPL.

Here comes the big distinction between libgnat which belongs to the FSF
and the other libraries which belong to AdaCore.

-- 
Ludovic Brenta.

Re: some questions on installing Ada on Linux

[brbarkstrom]

On Friday, July 4, 2014 6:16:10 AM UTC-4, Nasser M. Abbasi wrote:
> some basic questions. Goggling these is giving me hard so
> 
> I thought I ask here.
> 
> 
> 
> What is the correct way to install Ada on Linux these days?
> 
> I am on Linux mint 17.
> 
> 
> 
> 1) Should one install GNAT on Linux by downloading tar files from
> 
> http://libre.adacore.com  (GPL 2014 edition) or use
> 
> 
> 
>    sudo apt-get install gnat-4.8
> 
> 
> 
> 2) Will the sudo installation install all the stuff listed at
> 
> libre.adacore.com? including GPS editor and all the other
> 
> packages?
> 
> 
> 
> 3) Which is more recent, gnat-4.8 or GPL 2014 edition?
> 
> 
> 
> 4) When I go to http://libre.adacore.com/download/configurations
> 
> is there a way to tell it to check everything for download,
> 
> without one having to spend 1 hr clicking on the check-box
> 
> for each item? I do not see "select all"
> 
> 
> 
> It is really confusing having Ada/GNAT in 2 different places.
> 
> Why not have one place to install Ada from so it is less
> 
> confusing to users?
> 
> 
> 
> --Nasser

Most of the discussion in response to this question concentrates on 
licensing issues.

There is also a technical one.  The Linux distributions appear to maintain
provenance and metadata on a package basis.  The AdaCore GNAT
approach maintains the provenance and metadata on a compilation
unit basis.  Thus, if you look at the Debian Policy on Ada (a very
helpful document), you'll find that this distribution is not fully
compliant with the Ada library management standard.  I expect that
Red Hat, Fedora, and SuSE follow a similar centralized package maintenance
model.  AdaCore maintains the finer granularity approach and updates
the GPL code on a roughly annual basis.  The GPL licensing is one
component to enter the discussion.  This technical issue is another.
If you're only going to do Ada development and if you're into high
integrity language technologies, then the AdaCore nightly regression
testing may be important to you.

See also my post on "A Cautious Guide to Installing AdaCore GNAT GPL
on Ubuntu Linux".

Bruce B.

Re: some questions on installing Ada on Linux

[Simon Wright]

brbarkstrom@gmail.com writes:

> The Linux distributions appear to maintain provenance and metadata on
> a package basis.  The AdaCore GNAT approach maintains the provenance
> and metadata on a compilation unit basis.

I think this is a misunderstanding.

Debian builds its packages (pkgs in the following, to avoid ambiguity)
using GNAT, resulting in ALI and library files just as you would get on
any other system (modulo binary formats, of course).

The Debian Ada pkg scheme is "merely" a way of ensuring that the pkg
management system can work out how to get a consistent set of Ada
library pkgs on your machine. It would be no good to have an AWS pkg,
for example, that was built by gnat-4.6 if the gnat you have running is
gnat-4.7.

Re: some questions on installing Ada on Linux

[brbarkstrom]

On Friday, July 4, 2014 6:16:10 AM UTC-4, Nasser M. Abbasi wrote:
> some basic questions. Goggling these is giving me hard so
> 
> I thought I ask here.
> 
> 
> 
> What is the correct way to install Ada on Linux these days?
> 
> I am on Linux mint 17.
> 
> 
> 
> 1) Should one install GNAT on Linux by downloading tar files from
> 
> http://libre.adacore.com  (GPL 2014 edition) or use
> 
> 
> 
>    sudo apt-get install gnat-4.8
> 
> 
> 
> 2) Will the sudo installation install all the stuff listed at
> 
> libre.adacore.com? including GPS editor and all the other
> 
> packages?
> 
> 
> 
> 3) Which is more recent, gnat-4.8 or GPL 2014 edition?
> 
> 
> 
> 4) When I go to http://libre.adacore.com/download/configurations
> 
> is there a way to tell it to check everything for download,
> 
> without one having to spend 1 hr clicking on the check-box
> 
> for each item? I do not see "select all"
> 
> 
> 
> It is really confusing having Ada/GNAT in 2 different places.
> 
> Why not have one place to install Ada from so it is less
> 
> confusing to users?
> 
> 
> 
> --Nasser

In my Ada coding, I deprecate the Debian package and only use gnat, gcc,
and so on from the AdaCore download.  As I suggested, I value the consistency
with the Ada RM specs on library configurations more than I value the ease
of integrating with other languages or other packages.  The decision on
what to do is complex.  It doesn't just boil down to GPL versus other
licenses.

Bruce B.

Re: some questions on installing Ada on Linux

[Ludovic Brenta]

brbarkstrom@gmail.com writes:
> In my Ada coding, I deprecate the Debian package and only use gnat, gcc,
> and so on from the AdaCore download.  As I suggested, I value the consistency
> with the Ada RM specs on library configurations more than I value the ease
> of integrating with other languages or other packages.  The decision on
> what to do is complex.  It doesn't just boil down to GPL versus other
> licenses.

But as Simon pointed out, the Debian Policy for Ada ensures full
compliance with the Ada RM consistency rules.  In fact the main reason
for the existence of this Policy is to make binary packages (containing
.ali files) comply with the Ada RM consistency rules.  See in particular
the discussion of "the indirect FTBFS scenario", section 3.2.

Debian provides both ease of deployment and full compliance with Ada RM
consistency rules.  By design, no less.

-- 
Ludovic Brenta.

Re: some questions on installing Ada on Linux

[brbarkstrom]

On Friday, July 4, 2014 6:16:10 AM UTC-4, Nasser M. Abbasi wrote:
> some basic questions. Goggling these is giving me hard so
> 
> I thought I ask here.
> 
> 
> 
> What is the correct way to install Ada on Linux these days?
> 
> I am on Linux mint 17.
> 
> 
> 
> 1) Should one install GNAT on Linux by downloading tar files from
> 
> http://libre.adacore.com  (GPL 2014 edition) or use
> 
> 
> 
>    sudo apt-get install gnat-4.8
> 
> 
> 
> 2) Will the sudo installation install all the stuff listed at
> 
> libre.adacore.com? including GPS editor and all the other
> 
> packages?
> 
> 
> 
> 3) Which is more recent, gnat-4.8 or GPL 2014 edition?
> 
> 
> 
> 4) When I go to http://libre.adacore.com/download/configurations
> 
> is there a way to tell it to check everything for download,
> 
> without one having to spend 1 hr clicking on the check-box
> 
> for each item? I do not see "select all"
> 
> 
> 
> It is really confusing having Ada/GNAT in 2 different places.
> 
> Why not have one place to install Ada from so it is less
> 
> confusing to users?
> 
> 
> 
> --Nasser

After rereading section 3.2 (and subsections) of the Debian policy,
I will make my life as an Ada (almost entirely) developer simpler by
avoiding the Debian packaging as much as possible.  I do not have a
staff to assiduously comb through other packages to deal with the rules.
Also, I'm not trying to keep up with GNU GNAT.  I want the most stable
environment I can get.  That will become particularly important as I
start to work on an environment with concurrent processing, such as
a beowulf Linux cluster using PolyORB and the AWS.  As I said, there
are many dimensions to the decision.  I've made my choice.

Bruce B.

Re: some questions on installing Ada on Linux

[Ludovic Brenta]

brbarkstrom@gmail.com writes:
> After rereading section 3.2 (and subsections) of the Debian policy,
> I will make my life as an Ada (almost entirely) developer simpler by
> avoiding the Debian packaging as much as possible.  I do not have a
> staff to assiduously comb through other packages to deal with the rules.
> Also, I'm not trying to keep up with GNU GNAT.  I want the most stable
> environment I can get.  That will become particularly important as I
> start to work on an environment with concurrent processing, such as
> a beowulf Linux cluster using PolyORB and the AWS.  As I said, there
> are many dimensions to the decision.  I've made my choice.

Good luck compiling everything from source.

Debian package maintainers do all the "combing" for you and provide
precompiled packages.

But, if you use a derivative of Debian rather than Debian itself, you
might end up with packages that you cannot install concurrently.  This
depends on which versions of which packages the derivative (aka man in
the middle) chooses to carry.

The most stable Ada development *and deployment* environment in
existence today is Debian stable.

-- 
Ludovic Brenta.