[R-SIG-Mac] Making Fortran shared objects on Mac

[Emmanuel Sharef]

Hello all,

I get the following error when trying to compile some Fortran code to  
a shared object using R CMD SHLIB:

R CMD SHLIB test3.f
gfortran-4.0 -arch ppc   -fPIC  -g -O2 -c test3.f -o test3.o
gcc-4.0 -arch ppc -dynamiclib -Wl,-macosx_version_min -Wl,10.3 - 
undefined dynamic_lookup -single_module -multiply_defined suppress -L/ 
usr/local/lib -o test3.so test3.o -L/Library/Frameworks/R.framework/ 
Resources/lib/ppc -lRlapack -L/Library/Frameworks/R.framework/ 
Resources/lib/ppc -lRblas -lgfortran -lgcc_s -lSystemStubs -lmx - 
lSystem -lgfortran -lgcc_s -lSystemStubs -lmx -lSystem -L/Library/ 
Frameworks/R.framework/Resources/lib/ppc -lR -dylib_file  
libRblas.dylib:/Library/Frameworks/R.framework/Resources/lib/ppc/ 
libRblas.dylib
/usr/bin/libtool: unknown option character `m' in: -macosx_version_min
Usage: /usr/bin/libtool -static [-] file [...] [-filelist listfile 
[,dirname]] [-arch_only arch] [-sacLT]
Usage: /usr/bin/libtool -dynamic [-] file [...] [-filelist listfile 
[,dirname]] [-arch_only arch] [-o output] [-install_name name] [- 
compatibility_version #] [-current_version #] [-seg1addr 0x#] [- 
segs_read_only_addr 0x#] [-segs_read_write_addr 0x#] [-seg_addr_table  
<filename>] [-seg_addr_table_filename <file_system_path>] [-all_load]  
[-noall_load]
make: *** [test3.so] Error 1

It looks like it's having some trouble with libtool, but I don't know  
what it means. I have installed
- the Apple developer tools
- the gcc included with the R installer
- g77 from hpc.sourceforge.net

Am I perhaps missing something, or is something improperly configured?

Thanks,
Emmanuel