GNAT GPL 2016 on Debian Jessie

GNAT GPL 2016 on Debian Jessie

[Simon Wright]

I have 64-bit Debian Jessie (running under VMware Fusion).

I installed GNAT GPL 2016 (for experiments) and now find that gprbuild
can't find any compilers.

This is because gprconfig can't find any compilers:

   $ gprconfig
   No compilers found for target i686-pc-linux-gnu

gprconfig knows about the 2016 compiler,

   $ gprconfig --show-targets
   List of targets supported by a compiler:
   arm-eabi
   x86_64-pc-linux-gnu
   x86_64-linux-gnu

(the first x86_64 compiler is the GNAT GPL one, the other is jessie's).

I can work round this to an extent by setting up a default.cgpr, or
perhaps I could modify my GPRs; but, has anyone else got this setup
working out of the box?

Re: GNAT GPL 2016 on Debian Jessie

[rieachus]

On Monday, July 11, 2016 at 10:50:24 AM UTC-4, Simon Wright wrote:
> I have 64-bit Debian Jessie (running under VMware Fusion).

I don't quite understand your problem.  If you feel that GCC should have registered your compiler under one of hundreds of obsolete machine architectures, Waah!  x86-64 is a superset of i686, and a boatload of other architectures.

If you really want to generate i686 code, -march=i686 and usually -mtune=i686 as well should do the trick.  -march=native and -mtune=native will generate code for the specific machine hardware you are running on.  (I haven't tested what you get when you run on a virtual machine.)  I also haven't checked on how to run strict x86 (286 or earlier) code on x86-64 machines.  Normally OSes today will run code in (per compilation unit) either long (64-bit) mode or compatibility (32-bit) mode.  But no compiler should be generating the deprecated instructions that were eliminated from the -x86 instruction set to allow 64-bit addressing in 32-bit mode.  The instructions were deprecated precisely because most compilers generated more efficient code, and no compiler should be generating them today (or for that matter, in this century. ;-)

Re: GNAT GPL 2016 on Debian Jessie

[Simon Wright]

rieachus@comcast.net writes:

> On Monday, July 11, 2016 at 10:50:24 AM UTC-4, Simon Wright wrote:
>> I have 64-bit Debian Jessie (running under VMware Fusion).
>
> I don't quite understand your problem.  If you feel that GCC should
> have registered your compiler under one of hundreds of obsolete
> machine architectures, Waah!  x86-64 is a superset of i686, and a
> boatload of other architectures.

I wasn't clear enough.

The distributed gprbuild/gprconfig package was built on a machine with
i686-pc-linux-gnu, but the distributed GCC was built for
x86_64-pc-linux-gnu, so the distributed gprbuild/gprconfig was not
willing to treat the distributed GCC as a usable compiler unless it was
told to.

Thanks for the explanation, though.

GNAT GPL 2016 on Debian Jessie

[joakimds]

Dear Simon,

I have installed gnat gpl 2016 and remember having the same problem you describe. I remember that there was some configuration that was needed in order for gprbuild to be able to find gcc. Maybe I used "gnatls"... Sorry don't remember But I can confirm having sen your issue. I guess that by the time you read this you've already found a solution.

Best regards,
Joakim

Re: GNAT GPL 2016 on Debian Jessie

[ogpual]

I believe I asked about the converse problem here a month or so back.  I put the gnat gcc on my path ahead of the standard gcc that comes with linux,  and at least one other programming setup,  ie opam builds for  OCaml, would not work with the gnat binaries found  first on the path.

I believe that I have also seen the "No compilers" message.  Might it have been when the gnat binaries were hidden by being too far down the path? 

There is a new release of linux mint that has a newer version of the FSF gcc.  I hope to install that in the next few months and that it will be possible to use it for Ada programming well enough that I don't think it is a good idea to install the gnat binaries that conflict by name with the rest of the distro.

Re: GNAT GPL 2016 on Debian Jessie

[Simon Wright]

ogpual@gmail.com writes:

> I believe that I have also seen the "No compilers" message.  Might it
> have been when the gnat binaries were hidden by being too far down the
> path?

Thanks for the confirmation.

> There is a new release of linux mint that has a newer version of the
> FSF gcc.  I hope to install that in the next few months and that it
> will be possible to use it for Ada programming well enough that I
> don't think it is a good idea to install the gnat binaries that
> conflict by name with the rest of the distro.

I wanted to install GNATCOLL, because it includes GPR processing
support, which is needed for gpr_query, a tool to support Emacs
ada-mode. After eventually getting it to build, I went round the houses
a few times trying to install it; eventually realising that the sudo I'm
used to on macOS keeps the current PATH, but the Debian one doesn't
(even with -E), so when the Makefile runs gprinstall it picks up the
Debian one rather than the GNAT GPL one ...

Re: GNAT GPL 2016 on Debian Jessie

[Simon Wright]

Simon Wright <simon@pushface.org> writes:

> I have 64-bit Debian Jessie (running under VMware Fusion).
>
> I installed GNAT GPL 2016 (for experiments) and now find that gprbuild
> can't find any compilers.
>
> This is because gprconfig can't find any compilers:

It turns out that this was because I'd installed the arm-eabi compiler
over the x86_64 compiler.

Unlike the Mac versions I've been supporting over on Sourceforge, the
arm-eabi compiler contains its own gpr*, gps* versions (presumably so
that embedded developers don't need to download and install a hosted
compiler; but why wouldn't you?).

A fix that works for me is to install the cross compiler first, then
install the native compiler on top of it (I don't fancy having to use
different PATHs for the two targets, though I suppose you could put the
native compiler first and then the cross compiler, so that the cross
gpr* would never be seen).