<div dir="ltr">Dear cp2k developers, I want to use the libxc supporting version 2.4 of your software to do some calculations. As far as I know only version 2.0.1 of the libxc library is suitable for usage with cp2k up from version 2.4. My problem now is that, when I compiled (Intel compiler sets 12.1, 13.1 and 14.0) libxc 2.0.1 before proceeding with the compilation of the cp2k code, quite many of the test cases for the XC-functionals from this library failed, in particular the one for the gga_x_rpw86 functional I need. Since the compilation procedure for libxc is simple, I cannot imagine what could have went wrong. Strangely, the compilation of libxc 2.2.0, which I cannot use in cp2k, works absolutely fine and none of the test cases reports any error. My questions are: Did you check results of these test cases when you added libxc 2.0.1 to the list of libraries supported in cp2k 2.4 and did you observe similiar problem? Might there be just something wrong with the test cases themselves? Can one therefore ignore these failures? I asked this question to the libxc developers group, they did not reply yet, but I think this is an interesting issue for the users of cp2k in combination with libxc, especially because the 2.0.1 version is the only one we can use with cp2k. Thanks in advance, Mathias </div>