02:49 <iris1> Dear experts, I am having a problem with compilation. I am trying to (native) compile the example that comes from the Glpk module. Compiling example.ml to example.cmx goes fine, but in the second step, when I am trying to link stuff together with "ocamlopt glpk.cmxa -o example example.cmx", it fails with "/usr/bin/ld: cannot find -lglpk". I do have libglpk compiled but I am not able to install it outside my home directory. Therefore it

02:49 <iris1> like I should figure out what file it is looking for, then tell ocamlopt where that file lives. Can you please help? (I am using Ubuntu Server) Thank you very much!

03:15 <julm> iris1: your first post has been cut after "Therefore it" by the IRC server

03:15 <julm> iris1: perhaps have a glance at man 8 ld.so, especially around the environments variables like LD_LIBRARY_PATH

03:15 <iris1> The end is: ... Therefore it seems like I should figure out what file it is looking for, then tell ocamlopt where that file lives. Can you please help? (I am using Ubuntu Server) Thank you very much!

03:16 <julm> or passing a -rpath to ld

03:18 <iris1> Thank you very much for your advice!

03:18 <julm> with something like ocamlopt -cclib -Wl,-rpath=/home/your/lib/

03:18 <iris1> Let me try this...

03:18 <julm> (from memory, and I'm tired, but you got it)

03:21 <iris1> what do -Wl and -rpath do?

03:21 <julm> -Wl tells gcc to pass options to ld

03:21 <julm> -rpath adds a directory to the runtime library search path

03:22 <iris1> -rpath seems very useful. But the -Wl is confusing to me. Does gcc play a role in ocamlopt?

03:23 <julm> ocamlopt calls gcc, you can see it with -verbose IIRC

03:23 <julm> to do the linking

03:26 <iris1> it says gcc: unrecognized option '-rpath=/home/my/lib'

03:26 <julm> works here

03:27 <julm> have you well written "-Wl,-rpath" (no space)

03:29 <iris1> Ah no, sorry. You are right. With the no space, it does not complain about -rpath any more. However, it still cannot find -lglpk.

03:29 <iris1> What is the exact filename it is trying to find? libglpk.XXX?

03:30 <julm> probably libglpk.a or libglpk.so

03:31 <julm> do you have any /home/my/lib/libglpk.{a,so} ?

03:32 <iris1> yes I have both of them

03:34 <julm> -cclib -L/home/my/lib/ helps?

03:43 <iris1> YES!!! Thank you so much for your help!

03:44 <julm> lol, your welcome

03:45 <julm> you're*

03:48 <iris1> julm: may I ask you one last question?

03:48 <julm> yes, you may

03:48 <iris1> Thanks!

03:49 <iris1> This links glpk into my code dynamically, in that when I relocate my glpk compiled source tree, the example stops working

03:49 <iris1> is there a way to tell the linker to statically link glpk (only)?

03:50 <julm> that's likely due to the use of the hardcoded -rpath

03:50 <julm> you may try -cclib -Wl,-static

03:51 <julm> but to only statically link glpk I dunno; perhaps deleting the .so :>

03:51 <iris1> when I do --cclib -Wl,-static, the linker fails with "ld: cannot find -lgcc_s" ...

03:52 <julm> :/

03:56 <iris1> YES YES YES!! removing libglpk.so caused the compilation to result in an executable that keeps working when I relocate my compiled glpk tree. Thank you so much for your help!

03:59 <iris1> this would have taken me at least a week to figure out by myself :-)

04:12 <julm> :)

04:14 <julm> you could also hack around with -rpath=$ORIGIN/lib

04:14 <julm> man 8 ld.so

05:42 <thelema> mmm, I wish I had yield in ocaml

05:42 <thelema> (not yield thread, but to use inverted control flow of a generator)

05:49 <flux> thelema, use the continuations-library :)

05:50 <thelema> delimcc?

05:58 <flux> yes