diff --git a/pkgs/applications/version-management/subversion/default.nix b/pkgs/applications/version-management/subversion/default.nix
index 30283ad387c8..af9827ef4b85 100644
--- a/pkgs/applications/version-management/subversion/default.nix
+++ b/pkgs/applications/version-management/subversion/default.nix
@@ -46,8 +46,6 @@ stdenv.mkDerivation (rec {
 
   preBuild = ''
     makeFlagsArray=(APACHE_LIBEXECDIR=$out/modules)
-  '' + stdenv.lib.optionalString stdenv.isDarwin ''
-    substituteInPlace configure --replace "-no-cpp-precomp" ""
   '';
 
   postInstall = ''
diff --git a/pkgs/development/compilers/llvm/3.4/llvm.nix b/pkgs/development/compilers/llvm/3.4/llvm.nix
index fbc881fc8e02..dfd7b5570eae 100644
--- a/pkgs/development/compilers/llvm/3.4/llvm.nix
+++ b/pkgs/development/compilers/llvm/3.4/llvm.nix
@@ -65,6 +65,6 @@ in stdenv.mkDerivation rec {
     license     = stdenv.lib.licenses.bsd3;
     maintainers = with stdenv.lib.maintainers; [ shlevy lovek323 raskin viric ];
     platforms   = stdenv.lib.platforms.all;
-    broken      = stdenv.isDarwin;
+    # broken      = stdenv.isDarwin;
   };
 }
diff --git a/pkgs/development/libraries/libc++abi/default.nix b/pkgs/development/libraries/libc++abi/default.nix
index 8218cbb966f0..aae3027fd629 100644
--- a/pkgs/development/libraries/libc++abi/default.nix
+++ b/pkgs/development/libraries/libc++abi/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchsvn, libcxx, libunwind }:
+{ stdenv, fetchsvn, libcxx, libunwind, gnused }:
 let
   rev = "199626";
 in stdenv.mkDerivation {
@@ -15,17 +15,16 @@ in stdenv.mkDerivation {
   postUnpack = ''
     unpackFile ${libcxx.src}
     export NIX_CFLAGS_COMPILE="-I${libunwind}/include -I$PWD/include -I$(readlink -f libcxx-*)/include"
+    export TRIPLE=x86_64-apple-darwin
   '';
 
   installPhase = ''
     install -d -m 755 $out/include $out/lib
-    install -m 644 lib/libc++abi.so.1.0 $out/lib
+    install -m 644 lib/libc++abi.dylib $out/lib
     install -m 644 include/cxxabi.h $out/include
-    ln -s libc++abi.so.1.0 $out/lib/libc++abi.so
-    ln -s libc++abi.so.1.0 $out/lib/libc++abi.so.1
   '';
 
-  patchPhase = "sed -e s,-lstdc++,, -i lib/buildit";
+  patchPhase = "${gnused}/bin/sed -e s,-lstdc++,, -i lib/buildit";
 
   buildPhase = "(cd lib; ./buildit)";
 
diff --git a/pkgs/development/libraries/libunwind/native.nix b/pkgs/development/libraries/libunwind/native.nix
new file mode 100644
index 000000000000..dd2ebb6a6422
--- /dev/null
+++ b/pkgs/development/libraries/libunwind/native.nix
@@ -0,0 +1,22 @@
+{ stdenv }:
+
+stdenv.mkDerivation {
+  name = "libunwind-native";
+
+  unpackPhase = ":";
+  dontBuild = true;
+
+  installPhase = ''
+    mkdir -p $out/lib
+    cat ${/usr/lib/system/libunwind.dylib} > $out/lib/libunwind.dylib
+    /usr/bin/install_name_tool \
+      -change /usr/lib/system/libunwind.dylib ${/usr/lib/system/libunwind.dylib} \
+      -change /usr/lib/system/libsystem_malloc.dylib ${/usr/lib/system/libsystem_malloc.dylib} \
+      -change /usr/lib/system/libsystem_pthread.dylib ${/usr/lib/system/libsystem_pthread.dylib} \
+      -change /usr/lib/system/libsystem_platform.dylib ${/usr/lib/system/libsystem_platform.dylib} \
+      -change /usr/lib/system/libsystem_c.dylib ${/usr/lib/system/libsystem_c.dylib} \
+      -change /usr/lib/system/libdyld.dylib ${/usr/lib/system/libdyld.dylib} \
+      -change /usr/lib/system/libkeymgr.dylib ${/usr/lib/system/libkeymgr.dylib} \
+      $out/lib/libunwind.dylib
+  '';
+}
diff --git a/pkgs/development/libraries/mpc/default.nix b/pkgs/development/libraries/mpc/default.nix
index 3d05fa2e0405..dd132cfb5b7b 100644
--- a/pkgs/development/libraries/mpc/default.nix
+++ b/pkgs/development/libraries/mpc/default.nix
@@ -10,6 +10,8 @@ stdenv.mkDerivation rec {
 
   buildInputs = [ gmp mpfr ];
 
+  CFLAGS = "-I${gmp}/include";
+
   doCheck = true;
 
   meta = {
diff --git a/pkgs/development/libraries/mpfr/default.nix b/pkgs/development/libraries/mpfr/default.nix
index 653481aeccd6..d999ba0cda5c 100644
--- a/pkgs/development/libraries/mpfr/default.nix
+++ b/pkgs/development/libraries/mpfr/default.nix
@@ -10,6 +10,8 @@ stdenv.mkDerivation rec {
 
   buildInputs = [ gmp ];
 
+  CFLAGS = "-I${gmp}/include";
+
   configureFlags =
     /* Work around a FreeBSD bug that otherwise leads to segfaults in the test suite:
           http://hydra.bordeaux.inria.fr/build/34862
diff --git a/pkgs/development/libraries/serf/default.nix b/pkgs/development/libraries/serf/default.nix
index 033e53e521d5..49d7cec95901 100644
--- a/pkgs/development/libraries/serf/default.nix
+++ b/pkgs/development/libraries/serf/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, apr, scons, openssl, aprutil, zlib, krb5, pkgconfig }:
+{ stdenv, fetchurl, apr, scons, openssl, aprutil, zlib, krb5, pkgconfig, gnused }:
 
 stdenv.mkDerivation rec {
   name = "serf-1.3.7";
@@ -11,9 +11,9 @@ stdenv.mkDerivation rec {
   buildInputs = [ apr scons openssl aprutil zlib krb5 pkgconfig ];
 
   configurePhase = ''
-    sed -e '/^env[.]Append(BUILDERS/ienv.Append(ENV={"PATH":os.environ["PATH"]})' -i SConstruct
-    sed -e '/^env[.]Append(BUILDERS/ienv.Append(ENV={"NIX_CFLAGS_COMPILE":os.environ["NIX_CFLAGS_COMPILE"]})' -i SConstruct
-    sed -e '/^env[.]Append(BUILDERS/ienv.Append(ENV={"NIX_LDFLAGS":os.environ["NIX_LDFLAGS"]})' -i SConstruct
+    ${gnused}/bin/sed -e '/^env[.]Append(BUILDERS/ienv.Append(ENV={"PATH":os.environ["PATH"]})' -i SConstruct
+    ${gnused}/bin/sed -e '/^env[.]Append(BUILDERS/ienv.Append(ENV={"NIX_CFLAGS_COMPILE":os.environ["NIX_CFLAGS_COMPILE"]})' -i SConstruct
+    ${gnused}/bin/sed -e '/^env[.]Append(BUILDERS/ienv.Append(ENV={"NIX_LDFLAGS":os.environ["NIX_LDFLAGS"]})' -i SConstruct
   '';
 
   buildPhase = ''
diff --git a/pkgs/stdenv/darwin/default.nix b/pkgs/stdenv/darwin/default.nix
index 5c2044386c6e..d9668d0972cf 100644
--- a/pkgs/stdenv/darwin/default.nix
+++ b/pkgs/stdenv/darwin/default.nix
@@ -27,6 +27,11 @@ import ../generic rec {
     nativePrefix = stdenv.lib.optionalString stdenv.isSunOS "/usr";
     nativeLibc = true;
     inherit stdenv;
+    libcxx = pkgs.libcxx.override {
+      libcxxabi = pkgs.libcxxabi.override {
+        libunwind = pkgs.libunwindNative;
+      };
+    };
     binutils = import ../../build-support/native-darwin-cctools-wrapper {inherit stdenv;};
     clang = pkgs.clang_34;
     coreutils = pkgs.coreutils;
diff --git a/pkgs/tools/package-management/nix/default.nix b/pkgs/tools/package-management/nix/default.nix
index 6631214f39ab..e64bc3293939 100644
--- a/pkgs/tools/package-management/nix/default.nix
+++ b/pkgs/tools/package-management/nix/default.nix
@@ -22,6 +22,8 @@ stdenv.mkDerivation rec {
   postUnpack =
     '' export CPATH="${bzip2}/include"
        export LIBRARY_PATH="${bzip2}/lib"
+       export CXX=/usr/bin/clang++
+       export CXXFLAGS="-O3 -Wno-error=reserved-user-defined-literal"
     '';
 
   configureFlags =
@@ -32,7 +34,7 @@ stdenv.mkDerivation rec {
       --with-www-curl=${perlPackages.WWWCurl}/${perl.libPrefix}
       --disable-init-state
       --enable-gc
-      CFLAGS=-O3 CXXFLAGS=-O3
+      CFLAGS=-O3
     '';
 
   makeFlags = "profiledir=$(out)/etc/profile.d";
diff --git a/pkgs/tools/package-management/nix/unstable.nix b/pkgs/tools/package-management/nix/unstable.nix
index 5c20c7eb72aa..514924325e4a 100644
--- a/pkgs/tools/package-management/nix/unstable.nix
+++ b/pkgs/tools/package-management/nix/unstable.nix
@@ -1,5 +1,5 @@
 { stdenv, fetchurl, perl, curl, bzip2, sqlite, openssl ? null
-, pkgconfig, boehmgc, perlPackages
+, pkgconfig, boehmgc, perlPackages, bash
 , storeDir ? "/nix/store"
 , stateDir ? "/nix/var"
 }:
@@ -24,6 +24,7 @@ stdenv.mkDerivation rec {
   postUnpack =
     '' export CPATH="${bzip2}/include"
        export LIBRARY_PATH="${bzip2}/lib"
+       export CXXFLAGS="-O3 -Wno-error=reserved-user-defined-literal"
     '';
 
   configureFlags =
@@ -34,7 +35,7 @@ stdenv.mkDerivation rec {
       --with-www-curl=${perlPackages.WWWCurl}/${perl.libPrefix}
       --disable-init-state
       --enable-gc
-      CFLAGS=-O3 CXXFLAGS=-O3
+      CFLAGS=-O3
     '';
 
   makeFlags = "profiledir=$(out)/etc/profile.d";
diff --git a/pkgs/tools/text/sgml/opensp/default.nix b/pkgs/tools/text/sgml/opensp/default.nix
index 59b9b7bc13d1..71901b20ff1d 100644
--- a/pkgs/tools/text/sgml/opensp/default.nix
+++ b/pkgs/tools/text/sgml/opensp/default.nix
@@ -13,6 +13,11 @@ stdenv.mkDerivation {
       docsrc/*.xml
   '';
 
+  configureFlags = [
+    "--with-libintl-prefix=/usr"
+    "--with-libiconv-prefix=/usr"
+  ];
+
   setupHook = ./setup-hook.sh;
 
   buildInputs = [ xmlto docbook_xml_dtd_412 libxslt docbook_xsl ];
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index d4995b0e1d75..8e130d8c1b85 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -5699,6 +5699,8 @@ let
 
   libunwind = callPackage ../development/libraries/libunwind { };
 
+  libunwindNative = callPackage ../development/libraries/libunwind/native.nix {};
+
   libuvVersions = callPackage ../development/libraries/libuv { };
 
   libv4l = lowPrio (v4l_utils.override {