I'm having this error when building freefilesync on s390x architecture:
base/db_file.cpp:51:39: error: static assertion failed
51 | static_assert(std::endian::native == std::endian::little);
| ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
compilation terminated due to -Wfatal-errors.
make[1]: *** [Makefile:139: /tmp/FreeFileSync_Make/ffs/src/base/db_file.cpp.o] Error 1