Hi I have tried to implement the newest CLN version (cln-1.3.4) and ginac version (ginac-1.7.2). i am using gcc (GCC) 4.9.2 20150212 (Red Hat 4.9.2-6) (but also had the same problem with newer compilers) uname -a renders Linux 2.6.32-642.11.1.el6.x86_64 #1 SMP Tue Nov 15 14:13:21 CST 2016 x86_64 x86_64 x86_64 GNU/Linux CLN works, but for ginac i get checking readline/readline.h usability... no checking readline/readline.h presence... yes configure: WARNING: readline/readline.h: present but cannot be compiled configure: WARNING: readline/readline.h: check for missing prerequisite headers? configure: WARNING: readline/readline.h: see the Autoconf documentation configure: WARNING: readline/readline.h: section "Present But Cannot Be Compiled" configure: WARNING: readline/readline.h: proceeding with the compiler's result configure: WARNING: ## ---------------------------------- ## configure: WARNING: ## Report this to ginac-list@ginac.de ## configure: WARNING: ## ---------------------------------- ## checking for readline/readline.h... no checking readline/history.h usability... no checking readline/history.h presence... yes configure: WARNING: readline/history.h: present but cannot be compiled configure: WARNING: readline/history.h: check for missing prerequisite headers? configure: WARNING: readline/history.h: see the Autoconf documentation configure: WARNING: readline/history.h: section "Present But Cannot Be Compiled" configure: WARNING: readline/history.h: proceeding with the compiler's result configure: WARNING: ## ---------------------------------- ## configure: WARNING: ## Report this to ginac-list@ginac.de ## configure: WARNING: ## ---------------------------------- ## checking for readline/history.h... no and, when i ignore this and do make anyways, i have In file included from /home/trobens/programs/cln/install/include/cln/string.h:9:0, from /opt/rh/devtoolset-3/root/usr/include/c++/4.9.2/cstring:42, from class_info.h:27, from registrar.h:26, from basic.h:29, from ex.h:26, from expair.h:26, from expairseq.h:26, from add.h:26, from add.cpp:23: /opt/rh/devtoolset-3/root/usr/include/c++/4.9.2/cstring:75:11: error: ‘::memchr’ has not been declared using ::memchr; ^ /opt/rh/devtoolset-3/root/usr/include/c++/4.9.2/cstring:76:11: error: ‘::memcmp’ has not been declared using ::memcmp; ...etc ... which then leads to a stop in the compilation. i have tried various ways around this, if someone has a quick solution please let me know the same mistake occurs with earlier ginac versions and, as stated, with newer gccs (up to 6.1) ?? Thanks Best Tania Robens ------------------------------------------------------------------------- Dr. habil. Tania Robens Michigan State University Department of Physics and Astronomy 567 Wilson Road East Lansing, MI 48824 USA