zsnes: patches for modern gcc & libpng

builds fine on stdenv-updates now
needs gcc 4.8+, so keep this commit on stdenv-updates until merge

pkgs/misc/emulators/zsnes/default.nix

@@ -2,33 +2,27 @@
 
 stdenv.mkDerivation {
   name = "zsnes-1.51";
-  
+
   src = fetchurl {
     url = mirror://sourceforge/zsnes/zsnes151src.tar.bz2;
     sha256 = "08s64qsxziv538vmfv38fg1rfrz5k95dss5zdkbfxsbjlbdxwmi8";
   };
 
-  buildInputs = [ nasm SDL zlib libpng ncurses mesa ];
-  
+  # copied from arch linux, fixes gcc-4.8 compatibility
+  patches = [ ./zsnes.patch ];
+
+  postPatch = ''
+    patch -p0 < ${./zsnes-1.51-libpng15.patch}
+  '';
+
   preConfigure = ''
     cd src
-    
-    # Fix for undefined strncasecmp()
-    echo '#include <strings.h>' > tmp.cpp 
-    cat tmp.cpp tools/strutil.h > tools/strutil.h.new
-    mv tools/strutil.h.new tools/strutil.h
-    
-    # Fix for undefined system()
-    echo '#include <stdlib.h>' > tmp.cpp
-    cat tmp.cpp tools/depbuild.cpp > tools/depbuild.cpp.new
-    mv tools/depbuild.cpp.new tools/depbuild.cpp
-    
-    # Fix for lots of undefined strcmp, strncmp etc.
-    echo '#include <string.h>' > tmp.cpp 
-    cat tmp.cpp parsegen.cpp > parsegen.cpp.new
-    mv parsegen.cpp.new parsegen.cpp
   '';
-  
+
+  buildInputs = [ nasm SDL zlib libpng ncurses mesa ];
+
+  configureFlags = "--enable-release";
+
   meta = {
     description = "A Super Nintendo Entertainment System Emulator";
     license = "GPLv2+";