Re: [Caml-list] static C library of wrappers: compilation issues

[Xavier ALLAMIGEON <xavier.allamigeon@inria.fr>]

Dear Edwin,

Le 26/04/12 10:33, Török Edwin a écrit :
>> Here's the way I'm compiling everything. It builds a libhello_world.a static library from ml_code.obj.o and c_code.o.
>> ocamlc -c ml_code.mli
>> ocamlopt -c ml_code.ml
>> ocamlopt -output-obj ml_code.cmx -o ml_code.obj.o
>> gcc -c c_code.c -I"`ocamlc -where`"
>> ar rcs libhello_world.a ml_code.obj.o c_code.o
>> gcc -o test -L. -L"`ocamlc -where`" test.c -lhello_world -lasmrun -lm -ldl
>
> You need -Wl,--whole-archive -Wl,--no-whole-archive around the link of your .a, like this:
> gcc -o test -L. -L"`ocamlc -where`" test.c -Wl,--whole-archive -lhello_world -Wl,--no-whole-archive -lasmrun -lm -ldl
Thanks a lot, it works now!

> Otherwise the functions from your .a are dropped because nothing else before it needs it (-lasmrun would, but its after your .a).
What do you mean exactly? I imagine that test.o needs some functions of 
the libhello_world.a. But I don't see why libasmrun would need some 
other functions of libhello_world...

What about the following alternative where libasmrun is directly 
appended to the .a file?
cp "`ocamlc -where`"/libasmrun.a libhello_world.a
ar rcs libhello_world.a ml_code.obj.o c_code.o
gcc -o test -L. -L"`ocamlc -where`" test.c -lhello_world -lm -ldl

Best regards.
Xavier