> try compiling the following:

> cat << EOF > foo.c
> foo() {}
> EOF
> gcc -c foo.c
> ar cr libfoo.a foo.o
> ld -r -o xx.o -L. -lfoo -lfoo

err, the last line should read:

ld -r -u foo -o xx.o -L. -lfoo -lfoo

R.