Hi Mehdi,

I was able to reproduce the problem. Here is the output :

|-bash-4.1$ opam switch 4.02.3

=-=- Installing compiler 4.02.3 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
[default.comp] http://caml.inria.fr/pub/distrib/ocaml-4.02/ocaml-4.02.3.tar.gz downloaded
Now compiling OCaml. This may take a while, please bear with us...
[ERROR] Compiler build failed at "make world.opt":
        # opam-version 1.2.2
        # os           linux
        # command      make world.opt
        # path         /home/abenali/.opam/4.02.3/build/ocaml
        # exit-code    2
        # env-file     /home/abenali/.opam/log/log-30082-6d07ae.env
        # stdout-file  /home/abenali/.opam/log/log-30082-6d07ae.out
        # stderr-file  /home/abenali/.opam/log/log-30082-6d07ae.err
        ### stdout ###
        # [...]
        # ln -s ../byterun/debugger.c debugger.c
        # gcc -I../byterun -DCAML_NAME_SPACE -DNATIVE_CODE -DTARGET_none -DSYS_unknown  -O -Wall -D_FILE_OFFSET_BITS=64 -D_REENTRANT   -c -o debugger.o debugger.c
        # ln -s ../byterun/meta.c meta.c
        # gcc -I../byterun -DCAML_NAME_SPACE -DNATIVE_CODE -DTARGET_none -DSYS_unknown  -O -Wall -D_FILE_OFFSET_BITS=64 -D_REENTRANT   -c -o meta.o meta.c
        # ln -s ../byterun/dynlink.c dynlink.c
        # gcc -I../byterun -DCAML_NAME_SPACE -DNATIVE_CODE -DTARGET_none -DSYS_unknown  -O -Wall -D_FILE_OFFSET_BITS=64 -D_REENTRANT   -c -o dynlink.o dynlink.c
        # make[4]: Leaving directory `/gpfs/vesta-home/abenali/.opam/4.02.3/build/ocaml/asmrun'
        # make[3]: Leaving directory `/gpfs/vesta-home/abenali/.opam/4.02.3/build/ocaml'
        # make[2]: Leaving directory `/gpfs/vesta-home/abenali/.opam/4.02.3/build/ocaml'
        # make[1]: Leaving directory `/gpfs/vesta-home/abenali/.opam/4.02.3/build/ocaml'
        ### stderr ###
        # backtrace.c:103:14: warning: implicit declaration of function 'Callback_link' [-Wimplicit-function-declaration]
        # [...]
        #               ^
        # backtrace.c:103:44: warning: initialization makes pointer from integer without a cast [enabled by default]
        #        struct caml_context * next_context = Callback_link(*sp);
        #                                             ^
        # make[4]: *** No rule to make target `none.o', needed by `libasmrun.a'.  Stop.
        # make[3]: *** [makeruntimeopt] Error 2
        # make[2]: *** [opt-core] Error 2
        # make[1]: *** [opt.opt] Error 2
        # make: *** [world.opt] Error 2

-bash-4.1$  uname -a
Linux vestalac1 2.6.32-431.20.5.el6.ppc64 #1 SMP Wed Jul 16 05:27:12 EDT 2014 ppc64 ppc64 ppc64 GNU/Linux
|

and here is a bit of the /proc/cpuinfo:

|...
processor       : 47
cpu             : POWER7 (architected), altivec supported
clock           : 3720.000000MHz
revision        : 2.1 (pvr 003f 0201)

timebase        : 512000000
platform        : pSeries
model           : IBM,8205-E6B
machine         : CHRP IBM,8205-E6B
|

Using ocaml 4.03.0+dev12-2015-11-20 solved the problem, but I don’t more.

Cheers,
Anthony




On 01/20/2016 07:19 PM, Mehdi Dogguy wrote:

> On 19/01/2016 22:10, Mehdi Dogguy wrote:
>> Can you please tell us about the patches applied on top of 4.02.3 to get it
>> compiling? I've already compiled opam using ocaml 4.01 or 4.02 on ppc64el
>> without any issues. So, I am a bit surprised. Maybe I've missed something
>> though.
>>
> FWIW, the same question applies even one consider ppc64 (big endian), s390
> or s390x. In my experience, all four architectures didn't cause issues wrt.
> ocaml projects (or ocaml itself). So, I'm genuinely interested in hearing
> what could go (or went) wrong there and how observed issues were fixed.
>
> ocamlopt is certainly not available everywhere and sometimes, one has to
> put a little patch relevant on bytecode architectures. but i didn't see more
> complex or deep issues there.
>
​

-- 
Anthony Scemama
Laboratoire de Chimie et Physique Quantiques
IRSAMC - CNRS - Universite de Toulouse