On Wed, Aug 01, 2007 at 09:17:02AM -0700, Jos Backus wrote:
> On Wed, Aug 01, 2007 at 11:16:47AM +0200, Mauricio Fernandez wrote:
[snip]
> > If you could pinpoint the conversion that's triggering the problem (and it's
> > indeed a problem caused by a Ruby <-> OCaml conversion) we'd be one step
> > away from fixing it.  Have you tried to disassemble the extension and see
> > where caml_tuplify2 is being called?
> 
> I'll have a look. I do see references to caml_tuplify2 in other .a's as well.

It turns out my extension doesn't call it but one of the required libraries
does.

Here's what I am doing:

Exerpt from extconf.rb:

    # extension name, XXX in   require 'XXX'
    EXT_NAME = "kpp"

    Interface.generate("kpp") do
      def_class("KPP") do |c|
	t = c.abstract_type
	fun "make", STRING => t
	method "eval", [t, STRING] => LIST(STRING)
      end
    end

$ ruby extconf.rb
$ make
[lots of errors because of unfound header files]
$ vi Makefile
[Add `-I/usr/lib/ocaml' to INCFLAGS]
$ make
kpp_rocaml_wrapper.c:39: error: missing terminating " character
$ vi kpp_rocaml_wrapper.c
[Change line 39:

static VALUE String_list_caml_to_ruby(value v);"

to

static VALUE String_list_caml_to_ruby(value v);
]
$ make
gcc -I. -I/usr/lib/ruby/1.8/i386-linux -I/usr/lib/ruby/1.8/i386-linux -I. -I/usr/lib/ocaml  -fPIC -O2 -g -pipe -m32 -march=i386 -mtune=pentium4 -Wall  -fPIC  -c kpp_rocaml_wrapper.c
kpp_rocaml_wrapper.c: In function `string_ruby_to_caml_safe':
kpp_rocaml_wrapper.c:133: warning: implicit declaration of function `caml_alloc_string'
kpp_rocaml_wrapper.c: At top level:
kpp_rocaml_wrapper.c:45: warning: 'do_raise_exception' defined but not used
kpp_rocaml_wrapper.c:59: warning: 'do_raise_exception_tag' defined but not used
ocamlopt.opt -c   rubyOCamlUtil.ml
ocamlopt.opt  -output-obj -o kpp_rocaml_runtime.o nums.cmxa rubyOCamlUtil.cmx rubyOCamlUtil.o 
gcc -shared  -L"/usr/lib" -o kpp.so kpp_rocaml_wrapper.o kpp_rocaml_runtime.o /usr/lib/ocaml/libasmrun.a /usr/lib/ocaml/libunix.a /usr/lib/ocaml/libnums.a -lruby  -lpthread -ldl -lcrypt -lm   -lc
$ cat test_kpp.rb 
require 'kpp'

kpp = KPP.make ""
p kpp.eval("")
$ ruby test_kpp.rb 
test_kpp.rb:3:in `make': Couldn't find OCaml value 'KPP.make'. (StandardError)
        from test_kpp.rb:3
$ vi Makefile
[Add `-Wl,--whole-archive ../kpp/kpp.a -Wl,--no-whole-archive' to LOCAL_LIBS]
$ make clean all
$ ruby test_kpp.rb
./kpp.so: ./kpp.so: undefined symbol: camlStr__parse_368 - ./kpp.so (LoadError)
        from test_kpp.rb:1
$ vi Makefile
[Add `/usr/lib/ocaml/str.a' to LOCAL_LIBS]
$ make clean all
$ ruby test_kpp.rb
./kpp.so: ./kpp.so: undefined symbol: camlCamlinternalOO__create_object_opt_357 - ./kpp.so (LoadError)
        from test_kpp.rb:1
$ vi Makefile
[Add `/usr/lib/ocaml/stdlib.a' to LOCAL_LIBS]
$ make clean all
$ ruby test_kpp.rb
./kpp.so: ./kpp.so: undefined symbol: caml_hash_univ_param - ./kpp.so (LoadError)
        from test_kpp.rb:1
$ vi Makefile
[Add `/usr/lib/ocaml/libasmrun.a' (again) to LOCAL_LIBS]
$ make clean all
$ ruby test_kpp.rb
./kpp.so: ./kpp.so: undefined symbol: caml_tuplify2 - ./kpp.so (LoadError)
        from test_kpp.rb:1
$ 

At this point, LOCAL_LIBS looks like this:

LOCAL_LIBS = kpp_rocaml_runtime.o /usr/lib/ocaml/libasmrun.a \
    /usr/lib/ocaml/libunix.a /usr/lib/ocaml/libnums.a -Wl,--whole-archive \
    ../kpp/kpp.a -Wl,--no-whole-archive /usr/lib/ocaml/str.a \
    /usr/lib/ocaml/stdlib.a /usr/lib/ocaml/libasmrun.a
 
This is where I'm stuck.

-- 
Jos Backus
jos at catnook.com