Re: [Caml-list] Specifying a framework to link with using ocamlopt?

[Alan Schmitt <alan.schmitt@polytechnique.org>]

On 23 févr. 2011, at 16:48, David Allsopp wrote:

> Yes and no. I think there's a warning missing in ocamlmklib. Essentially, you're meant to pass some C object files (the stubs) whenever you use ocamlmklib - I think that what's going on is that because there are no .o files passed, it's not compiling libGL.a and so the linking instruction included is failing. ocamlmklib probably should warn that you passed no c objects and libGL.a doesn't seem to exist either. 
> 
> That said, I think it's that you're using ocamlmklib in a weird way by compiling the stubs separately and renaming the library that's causing the problems. The -lGL is added because of the -o GL. Try passing -oc gl_stubs to your second ocamlmklib call as well or alternatively do it as one:
> 
> ocamlmklib -verbose -o GL -oc gl_stubs GL.cmx -framework OpenGL GL.cmx gl.wrap.o
> 
> but you can safely omit the -oc gl_stubs if you're happy for the stub library to be libGL.a instead. Does that work?

It seems that using the gl_stubs bit is necessary. Otherwise I get:
[:)][top] % ocamlmklib -verbose -o GL -framework OpenGL GL.cmx gl.wrap.o
+ gcc -bundle -flat_namespace -undefined suppress -o ./dllGL.so gl.wrap.o -L/Users/schmitta/godi/lib -framework OpenGL   
+ ar rc ./libGL.a  gl.wrap.o; ranlib ./libGL.a
+ /Users/schmitta/godi/bin/ocamlopt -a -o GL.cmxa  GL.cmx -cclib -lGL -ccopt -L/Users/schmitta/godi/lib -ccopt -framework -ccopt OpenGL   

where the -lGL is still there.

With you other command line (removing the duplicated instance of "GL.cmx"), it works much better:

[:)][top] % ocamlmklib -verbose -o GL -oc gl_stubs GL.cmx -framework OpenGL gl.wrap.o
+ gcc -bundle -flat_namespace -undefined suppress -o ./dllgl_stubs.so gl.wrap.o -L/Users/schmitta/godi/lib -framework OpenGL   
+ ar rc ./libgl_stubs.a  gl.wrap.o; ranlib ./libgl_stubs.a
+ /Users/schmitta/godi/bin/ocamlopt -a -o GL.cmxa  GL.cmx -cclib -lgl_stubs -ccopt -L/Users/schmitta/godi/lib -ccopt -framework -ccopt OpenGL   

Applying the same recipe to the other libraries solved the issue. Thanks a bunch!

Alan