anchor.diff:      sha256 = "0mkrzxpf42lmn96khfl1791vram67r2nqsgmppd2yil889nyz5kp";
     };
   
  -  /* FIXME: Ruby currently disabled because of this:
  -
  -     Linking C shared library ../src/.libs/libsimgrid.so
  -     ld: cannot find -lruby-1.8.7-p72
  -
  -   */
  -  buildInputs = [ cmake perl /* ruby */ boost ];
  +  buildInputs = [ cmake perl ruby boost lua5_1 graphviz libsigcxx libunwind
  +    elfutils
  +    ];
   
     preConfigure =
       # Make it so that libsimgrid.so will be found when running programs from
  
positive.code:     '' export LD_LIBRARY_PATH="$PWD/src/.libs"
         export cmakeFlags="-Dprefix=$out"
  
         # Enable tracing.
         export cmakeFlags="$cmakeFlags -Denable_tracing=on"
      '';
  
    makeFlags = "VERBOSE=1";
  
negative.code: { fetchurl, stdenv, cmake, perl, ruby, boost, lua5_1, graphviz, libsigcxx
  , libunwind, elfutils
  }:
  
  stdenv.mkDerivation rec {
    version = "3.11.1";
  