This issue is covered in more detail here: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=917675

As a result of this bug, sfepy has been removed from Debian Testing, which would prevent it from being included in the upcoming Debian 10 release.

An abbreviated error message is:

sfepy/discrete/common/extmods/common.h:109:59: error: expected expression before ')' token