Building a Windows LIB

[Bruce M. Axtens]

G'day everyone

According to the friendly manual at 
<http://gmplib.org/manual/Notes-for-Particular-Systems.html#Notes-for-Particular-Systems>:

  A MINGW DLL build of GMP can be used with Microsoft C. Libtool doesn't 
install a .lib format import library, but it can be created with MS lib 
as follows,
 and copied to the install directory. Similarly for libmp and libgmpxx.

  cd .libs
  lib /def:libgmp-3.dll.def /out:libgmp-3.lib

Where do I find the .def file? It doesn't appear to be generated (and 
I've tried a variety of parameters on 'configure').

Kind regards,
Bruce.