Modified SDL2 derivation to work on Mac OSX darwin

default to no alsa on darwin
default to no x11 support on darwin
changed asserts to check for darwin

pkgs/development/libraries/SDL2/default.nix

@@ -7,9 +7,9 @@
 
 # OSS is no longer supported, for it's much crappier than ALSA and
 # PulseAudio.
-assert alsaSupport || pulseaudioSupport;
+assert !stdenv.isDarwin -> alsaSupport || pulseaudioSupport;
 
-assert openglSupport -> (mesa != null && x11Support);
+assert openglSupport -> (stdenv.isDarwin || mesa != null && x11Support);
 assert x11Support -> (x11 != null && libXrandr != null);
 assert alsaSupport -> alsaLib != null;
 assert pulseaudioSupport -> pulseaudio != null;
@@ -59,7 +59,7 @@ stdenv.mkDerivation rec {
     description = "A cross-platform multimedia library";
     homepage = http://www.libsdl.org/;
     license = stdenv.lib.licenses.zlib;
-    platforms = stdenv.lib.platforms.linux;
+    platforms = stdenv.lib.platforms.all;
     maintainers = [ stdenv.lib.maintainers.page ];
   };
 }

pkgs/top-level/all-packages.nix

@@ -7146,8 +7146,8 @@ let
 
   SDL2 = callPackage ../development/libraries/SDL2 {
     openglSupport = mesaSupported;
-    alsaSupport = true;
-    x11Support = true;
+    alsaSupport = (!stdenv.isDarwin);
+    x11Support = (!stdenv.isDarwin);
     pulseaudioSupport = false; # better go through ALSA
   };