Adding a new version of the gcc-wrapper, named gcc-wrapper2, in order not to rebuild

stdenv.

In this gcc-wrapper2 I made the ld-wrapper.sh to handle the linking with shared
objects through direct pass as ld command arguments of the absolute path to shared
objects, instead of using the -L/-l combinations.

cmake 'FindXXX.cmake' modules make a strong usage of the dynamic linking directly
passing the absolute path to the shared object to the linker, and as our wrapper did
not add any -rpath for those, writting the nix expressions for some cmake packages
resulted in a lot of tricks, compared to using this gcc-wrapper2.

This gcc-wrapper2/ld-wrapper.sh should become the gcc-wrapper/ld-wrapper in a
stdenv update.

I also updated some cmake expressions to use this gcc-wrapper2, and reduced its
tricks.

I also updated the cmake setup-hook for it to make cmake not touch any rpath decided
at build time, when running the 'make install' of makefiles created by cmake.

svn path=/nixpkgs/trunk/; revision=18885

pkgs/applications/graphics/freepv/default.nix

@@ -17,26 +17,6 @@ stdenv.mkDerivation {
     sed -i -e '/mozilla/d' src/CMakeLists.txt
   '';
 
-  # I added these flags to get all the rpaths right, which I guess they are
-  # taken from the qt4 sources. Not very nice.
-  cmakeFlags = " -DCMAKE_EXE_LINKER_FLAGS=\"" +
-    " -lpng12 -lXxf86vm -ljpeg -lz -lglut -lGLU -lxml2 -lX11\"" +
-    " -DCMAKE_SKIP_BUILD_RPATH=ON" +
-    " -DCMAKE_BUILD_TYPE=Release" +
-    " -DCMAKE_INSTALL_PREFIX=$out";
-
-  dontUseCmakeConfigure = true;
-
-  # I rewrote the configure phase to get the $out references evaluated in
-  # cmakeFlags
-  configurePhase = ''
-    set -x
-    mkdir -p build;
-    cd build
-    eval -- "cmake .. $cmakeFlags"
-    set +x
-    '';
-
   meta = {
     description = "Open source panorama viewer using GL";
     homepage = http://freepv.sourceforge.net/;