Re: [Rd] modules with libtool and -dlpreopen

From: Marcus G. Daniels <>
Date: Thu 03 Feb 2005 - 11:44:51 EST

Prof Brian Ripley wrote:

> Some of them use Fortran, please note, and libtool is none too good at > that.

I didn't have an (obvious) problem with that. I did notice that DYLIB_* variables in didn't have USE_LIBTOOL_TRUE/FALSE conditionalizations. That was a place it broke for me with Fortran code in modules. Was it a compile-time problem or a run-time problem you saw?

Also I noticed compilation invocations weren't set up in R 2.0.1 to prepend "libtool --mode=compile". When I inserted those for C and Fortran, reactivated the linkage code for libtool that was already there, and then went through each module and made *.lo the dependency instead of *.o, and made *.la the target instead of *.so, I managed to get (.la) modules installed in the build tree under /build/R/library/{tools,grid,methods,splines,stats,tools).

Next I went to the src/unix directory and removed the object code, and rebuilt using:

make CPPFLAGS='-Ddlsym=lt_dlsym -Ddlopen=lt_dlopen -Ddlclose=lt_dlclose'

After that I went back to the src/main directory and first edited Rmain.c to add an include of ltdl.h , a call to LTDL_SET_PRELOADED_SYMBOLS() and a call to "lt_dlinit ()" before "Rf_initialize_R (ac, av)".

Then I modified the linkage of R.bin to add this at the start of the command:

-dlpreopen /build/R/library/tools/libs/ -dlpreopen

/build/R/library/stats/libs/ -dlpreopen 
/build/R/library/methods/libs/ -dlpreopen 
/build/R/library/grid/libs/ -dlpreopen 



at the end of the link (the libtool dlopen compatibility interface).

Following that I just went to the top of the build tree of R and let the build finish.

As you can see, no calls to dlsym get made:

$ R_HOME=/build/R gdb ./R.bin -q
Using host libthread_db library "/lib/tls/".
(gdb) break main

Breakpoint 1 at 0x8060c52: file /src/R-2.0.1/src/main/Rmain.c, line 32.
(gdb) run -q

Starting program: /build/R/src/main/R.bin -q

Breakpoint 1, main (ac=2, av=0xfefbce44) at /src/R-2.0.1/src/main/Rmain.c:32 32 {
(gdb) break dlsym

Breakpoint 2 at 0xf6fa3de6
(gdb) c

Detaching after fork from child process 6376.  >

Compare this to a default build of R on Linux that would have them:

$ R -d 'gdb -q' -q
(no debugging symbols found)...Using host libthread_db library
(gdb) break main

Breakpoint 1 at 0x805ceb6
(gdb) run -q

Starting program: /usr/lib/R/bin/exec/R -q
(no debugging symbols found)...(no debugging symbols found)...
Breakpoint 1, 0x0805ceb6 in main ()
(gdb) break dlsym

Breakpoint 2 at 0xf6f55de6
(gdb) c


Breakpoint 2, 0xf6f55de6 in dlsym () from /lib/
(gdb) mailing list Received on Thu Feb 03 10:49:34 2005

This archive was generated by hypermail 2.1.8 : Fri 18 Mar 2005 - 09:02:44 EST