clisp: Unbreak on Darwin

Clisp depended on libffcall, which does not compile on Darwin.  The
dependency is optional though, so omit it on Darwin.  Also, make
conditional transitive dependencies on libffcall.

pkgs/development/interpreters/clisp/default.nix

@@ -5,18 +5,18 @@
 # - full: contains base plus modules in withModules
 { stdenv, fetchurl, libsigsegv, gettext, ncurses, readline, libX11
 , libXau, libXt, pcre, zlib, libXpm, xproto, libXext, xextproto
-, libffi, libffcall, coreutils
+, libffi
+, libffcall
+, coreutils
 # build options
 , threadSupport ? (stdenv.isi686 || stdenv.isx86_64)
 , x11Support ? (stdenv.isi686 || stdenv.isx86_64)
 , dllSupport ? true
 , withModules ? [
-    "bindings/glibc"
     "pcre"
     "rawsock"
-    "wildcard"
-    "zlib"
   ]
+  ++ stdenv.lib.optionals stdenv.isLinux [ "bindings/glibc" "zlib" "wildcard" ]
   ++ stdenv.lib.optional x11Support "clx/new-clx"
 }:
 
@@ -33,15 +33,17 @@ stdenv.mkDerivation rec {
   };
 
   inherit libsigsegv gettext coreutils;
-  
+
+  ffcallAvailable = stdenv.isLinux && (libffcall != null);
+
   buildInputs = [libsigsegv]
   ++ stdenv.lib.optional (gettext != null) gettext
   ++ stdenv.lib.optional (ncurses != null) ncurses
   ++ stdenv.lib.optional (pcre != null) pcre
   ++ stdenv.lib.optional (zlib != null) zlib
   ++ stdenv.lib.optional (readline != null) readline
-  ++ stdenv.lib.optional (libffi != null) libffi
-  ++ stdenv.lib.optional (libffcall != null) libffcall
+  ++ stdenv.lib.optional (ffcallAvailable && (libffi != null)) libffi
+  ++ stdenv.lib.optional ffcallAvailable libffcall
   ++ stdenv.lib.optionals x11Support [
     libX11 libXau libXt libXpm xproto libXext xextproto
   ];
@@ -64,8 +66,10 @@ stdenv.mkDerivation rec {
   configureFlags = "builddir"
   + stdenv.lib.optionalString (!dllSupport) " --without-dynamic-modules"
   + stdenv.lib.optionalString (readline != null) " --with-readline"
-  + stdenv.lib.optionalString (libffi != null) " --with-dynamic-ffi"
-  + stdenv.lib.optionalString (libffcall != null) " --with-ffcall"
+  # --with-dynamic-ffi can only exist with --with-ffcall - foreign.d does not compile otherwise
+  + stdenv.lib.optionalString (ffcallAvailable && (libffi != null)) " --with-dynamic-ffi"
+  + stdenv.lib.optionalString ffcallAvailable " --with-ffcall"
+  + stdenv.lib.optionalString (!ffcallAvailable) " --without-ffcall"
   + stdenv.lib.concatMapStrings (x: " --with-module=" + x) withModules
   + stdenv.lib.optionalString threadSupport " --with-threads=POSIX_THREADS";
 
@@ -88,6 +92,6 @@ stdenv.mkDerivation rec {
     description = "ANSI Common Lisp Implementation";
     homepage = http://clisp.cons.org;
     maintainers = with stdenv.lib.maintainers; [raskin tohl];
-    platforms = stdenv.lib.platforms.linux;
+    platforms = stdenv.lib.platforms.unix;
   };
 }