Missing library cygwin-ruby16

To build a Ruby package involving C code under Cygwin, you need to link
with cygwin-ruby.dll, right? I’m trying to build the “oracle” package in
order to give myself some dbi bliss, but it’s not complying. ‘ld’ is
complaining that it can’t find ‘-lcygwin-ruby16’, by which I assume it
means ‘libcygwin-ruby16.a’.

I’ve tried creating a .a file from /usr/local/bin/cygwin-ruby.dll using
’dlltool’, but the result was pretty bare (~1k) because I don’t have a
.def file for input.

I am not an expert in any of these areas. Can anyone give any pointers?
Has anyone successfully built the “oracle” package under Cygwin OR native

Using ruby-1.6.5.