When I try compile alps-2.3.0 with python 2.7 error comes: [ 23%] Building CXX object src/alps/CMakeFiles/alps.dir/alea/ observablefactory.C.o In file included from /home/tadeusz/alps-2.3.0-src-with-boost/alps/src/alps/ alea/histogrameval.h:36, from /home/tadeusz/alps-2.3.0-src-with-boost/alps/src/alps/ alea/observablefactory.C:38: /home/tadeusz/alps-2.3.0-src-with-boost/alps/src/alps/alea/histogram.h: In member function 'alps::HistogramObservable<T>::const_iterator alps:: HistogramObservable<T>::rbegin() const': /home/tadeusz/alps-2.3.0-src-with-boost/alps/src/alps/alea/histogram.h:88:59: error: could not convert '((const alps::HistogramObservable <T>*)this)->alps::HistogramObservable<T>::histogram_.std::vector<unsigned int>::rbegin()' from 'std::vector<unsigned int>::reverse_iterator' {aka 'std::reverse_iterator<__gnu_cxx::__normal_iterator<unsigned int*, std::vector<unsigned int> > >'} to 'alps::HistogramObservable<T>::const_iterator' {aka '__gnu_cxx::__normal_iterator<const unsigned int*, std::vector<unsigned int> >'} const_iterator rbegin() const { return histogram_.rbegin();} ~~~~~~~~~~~~~~~~~^~ /home/tadeusz/alps-2.3.0-src-with-boost/alps/src/alps/alea/histogram.h: In member function 'alps::HistogramObservable<T>::const_iterator alps:: HistogramObservable<T>::rend() const': /home/tadeusz/alps-2.3.0-src-with-boost/alps/src/alps/alea/histogram.h:90:55: error: could not convert '((const alps::HistogramObservable <T>*)this)->alps::HistogramObservable<T>::histogram_.std::vector<unsigned int>::rend()' from 'std::vector<unsigned int>::reverse_iterator' {aka 'std::reverse_iterator<__gnu_cxx::__normal_iterator<unsigned int*, std::vector<unsigned int> > >'} to 'alps::HistogramObservable<T>::const_iterator' {aka '__gnu_cxx::__normal_iterator<const unsigned int*, std::vector<unsigned int> >'} const_iterator rend() const { return histogram_.rend();} ~~~~~~~~~~~~~~~^~ make[2]: *** [src/alps/CMakeFiles/alps.dir/build.make:154: src/alps/ CMakeFiles/alps.dir/alea/observablefactory.C.o] Error 1 make[1]: *** [CMakeFiles/Makefile2:1216: src/alps/CMakeFiles/alps.dir/all] Error 2 make: *** [Makefile:163: all] Error 2 However when I try python 3.7 error is different: [ 11%] Building CXX object src/boost/CMakeFiles/boost.dir/home/tadeusz /alps-2.3.0-src-with-boost/boost/libs/python/src/converter/builtin _converters.cpp.o /home/tadeusz/alps-2.3.0-src-with-boost/boost/libs/python/src/converter/ builtin_converters.cpp: In function 'void* boost::python::converter::{anonymous}::convert_to_cstring(PyObject*)': /home/tadeusz/alps-2.3.0-src-with-boost/boost/libs/python/src/converter/ builtin_converters.cpp:51:35: error: invalid conversion from 'const void*' to 'void*' [-fpermissive] return PyUnicode_Check(obj) ? _PyUnicode_AsString(obj) : 0; make[2]: *** [src/boost/CMakeFiles/boost.dir/build.make:1376: src/boost/ CMakeFiles/boost.dir/home/tadeusz/alps-2.3.0-src -with-boost/boost/libs/python/src/converter/builtin_converters.cpp.o] Error 1 make[1]: *** [CMakeFiles/Makefile2:1013: src/boost/CMakeFiles/boost.dir/all] Error 2 make: *** [Makefile:163: all] Error 2 where is the problem? cmake looks good - see attached files my system is archlinux, gcc:8.2.1, openmpi: 3.1, cmake: 3.12 Tadeusz Wasiutyński