mcxx: add mcxx from the git repo

bsc/mcxx/git.nix

@@ -0,0 +1,60 @@
+{
+  stdenv
+, fetchFromGitHub
+, autoreconfHook
+, nanos6
+, gperf
+, python
+, gfortran
+, pkg-config
+, sqlite
+, flex
+, bison
+, gcc
+}:
+
+stdenv.mkDerivation rec {
+  pname = "mcxx";
+  version = src.shortRev;
+
+  passthru = {
+    CC = "mcc";
+    CXX = "mcxx";
+  };
+
+  src = builtins.fetchGit {
+    url = "ssh://git@bscpm03.bsc.es/mercurium/mcxx";
+    ref = "master";
+  };
+
+  enableParallelBuilding = true;
+
+  buildInputs = [
+    autoreconfHook
+    nanos6
+    gperf
+    python
+    gfortran
+    pkg-config
+    sqlite.dev
+    bison
+    flex
+    gcc
+  ];
+
+  # TODO: Not sure if we need this patch anymore (?)
+  #patches = [ ./intel.patch ];
+
+  preConfigure = ''
+    export ICC=icc
+    export ICPC=icpc
+    export IFORT=ifort
+  '';
+
+  configureFlags = [
+    "--enable-ompss-2"
+    "--with-nanos6=${nanos6}"
+# Fails with "memory exhausted" with bison 3.7.1
+#    "--enable-bison-regeneration"
+  ];
+}

overlay.nix

@@ -68,6 +68,7 @@ let
 
     mcxx = bsc.mcxxRelease;
     mcxxRelease = callPackage ./bsc/mcxx/default.nix { };
+    mcxxGit = callPackage ./bsc/mcxx/git.nix { };
     mcxxRarias = callPackage ./bsc/mcxx/rarias.nix {
       bison = self.bison_3_5;
     };