Re: Example in ECL repository for static link

Hey Thomas,



------- Original Message -------
On Monday, June 19th, 2023 at 5:34 PM, Thomas Teixeira <thomas.teixeira@sta=
rtmail.com> wrote:


> Hi !
> Thanks for ECL, I've been learning CL for the past weeks and it's my favo=
rite
> implementation so far ! Would love to contribute one I've the required sk=
ills
> :))

That sounds great :)

>=20
> I'm trying to create a small script that'll allow users to recreate a mai=
l
> thread inside a virtual maildir box. I would like to use ECL for that scr=
ipt but
> the project which this script will belong to ([fruitslegumes][1]) is focu=
sed on
> using no dependencies.

Does libc count as a dependency? Currently ECL links dynamically against li=
bc even
for static builds. There are no technical reasons why it couldn't link stat=
ically
against libc (and we want to allow that), but currently flags in multiple p=
laces
simply assume a dynamic link.

>=20
> Because of this constraint, I only ever used POSIX-shell/C99 to build tho=
se
> scripts
> I would love to use ECL as programs can be compiled down to machine code,=
 which
> can be `upx`-ed, but users would have to install their ecl package.
>=20
> I managed to statically link libecl with a simple script, but it gets har=
der for
> me when trying with the example-with-dep program.
> I saw in a previous thread of this mailing list that statically linking E=
CL
> makes asdf unusable. Is that still the case ?

It is not that ASDF is unusable when we link statically. There are a few ra=
mifications
though. I'll elaborate a little here about FASL files in ECL:

> Would it be possible to either provide an example (if what i'm asking is =
even
> possible) or talk in more depth about ecl being statically linked ?

The fasl file created by ECL is a shared object that is linked dynamically =
against
libecl.so. If it were a static object, then each and every fasl would need =
to carry
whole ECL runtime statically linked. That's not a sound solution.

Now, regarding using ASDF in static builds. When the C compiler is not inst=
alled
(either not build with ECL, or (ext:install-bytecodes-compiler) was called)=
, then
files compiled by ECL are in FASC format, that is the bytecode. Such byteco=
de may
be loaded with statically linked ECL. ASDF should work fine with FASC files=
, although
some libraries may assume the C compiler, so not all software will work wit=
h it.

If you want to have ASDF statically linked in the resulting binary, you nee=
d to specify
that when building ECL. For example ./configure --disable-shared --with-asd=
f=3Dbuiltin .

There's also that you may compile your lisp source code along with ECL and =
statically
link it (that would be somewhat similar to the example with deps), although=
 there is
no explicit support for ASDF. To specify files that should be compiled and =
linked with
ECL you may specify the flag --with-extra-files.

As you can see, static linking is somewhere in the ballpark of what ECL can=
 do, but
it is not well supported. I'm working on some compiler improvements to allo=
w easier
cross compilation and other similar things and hope that during that work I=
'll also
improve the support for static builds (although that is not the main focus)=
.

I hope that this explanation is at least partly satisfactory.

>=20
> Regards,
> Thomas.

Best regards,
Daniel


--
Daniel Kochma=C5=84ski ;; aka jackdaniel | Przemy=C5=9Bl, Poland
TurtleWare - Daniel Kochma=C5=84ski=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 | www.tur=
tleware.eu

"Be the change that you wish to see in the world." - Mahatma Gandhi