Add GHC-7.8.1-rc2.

pkgs/development/compilers/ghc/7.8.1.nix

@@ -0,0 +1,45 @@
+{ stdenv, fetchurl, ghc, perl, gmp, ncurses }:
+
+stdenv.mkDerivation rec {
+  version = "7.8.0.20140228";
+  name = "ghc-${version}";
+
+  src = fetchurl {
+    url = "http://www.haskell.org/ghc/dist/7.8.1-rc2/${name}-src.tar.bz2";
+    sha256 = "09xlgz1xg0182wjy62h3j0xvnhllhjlyvj30vc3him98parnr76w";
+  };
+
+  buildInputs = [ ghc perl gmp ncurses ];
+
+  enableParallelBuilding = true;
+
+  buildMK = ''
+    libraries/integer-gmp_CONFIGURE_OPTS += --configure-option=--with-gmp-libraries="${gmp}/lib"
+    libraries/integer-gmp_CONFIGURE_OPTS += --configure-option=--with-gmp-includes="${gmp}/include"
+    DYNAMIC_BY_DEFAULT = NO
+  '';
+
+  preConfigure = ''
+    echo "${buildMK}" > mk/build.mk
+    sed -i -e 's|-isysroot /Developer/SDKs/MacOSX10.5.sdk||' configure
+    export NIX_LDFLAGS="$NIX_LDFLAGS -rpath $out/lib/ghc-${version}"
+  '';
+
+  configureFlags = "--with-gcc=${stdenv.gcc}/bin/gcc";
+
+  # required, because otherwise all symbols from HSffi.o are stripped, and
+  # that in turn causes GHCi to abort
+  stripDebugFlags = [ "-S" "--keep-file-symbols" ];
+
+  meta = {
+    homepage = "http://haskell.org/ghc";
+    description = "The Glasgow Haskell Compiler";
+    maintainers = [
+      stdenv.lib.maintainers.marcweber
+      stdenv.lib.maintainers.andres
+      stdenv.lib.maintainers.simons
+    ];
+    inherit (ghc.meta) license platforms;
+  };
+
+}