[Ur] problems building Ur/Web on OS X since the change to dynamic so libs

[Adam Chlipala]

Georg Bauer wrote:
> since the change to dynamically loaded liburweb about 3 weeks ago,
> there is a problem with building on OS X: (only noticed it today when
> trying to build the new version)
>
> gcc -shared -Wl,-soname,liburweb.so.1 -o lib/c/liburweb.so.1.0
> lib/c/memmem.do lib/c/urweb.do lib/c/queue.do lib/c/request.do
> lib/c/mhash.do
> ld: unknown option: -soname
> collect2: ld returned 1 exit status
>
> The relevant change is
>
> Makefile.in @ 1095:bed675db3aff
>
> OS X doesn't have a -soname parameter due to the different form of
> dynamic libs (they are dylib bundles there, not so files). No idea if
> anyone has a patch to fix that, but for now it doesn't build on OS X
> (before it did compile and run just fine).
>    

I don't know anything about the OSX development environment.  I'll be 
happy to accept any patch someone provides.