When I try to build libsigrok on Arch Linux I get linker errors on classes.cpp. The reason is that enums.cpp of cxx binding is not generated properly by doxygen 1.8.16. doxy/xml/index.xml is generated but it seems to be incomplete. When downgrading doxygen to version 1.8.15 build of libsigrok succeeds.
Marking this one as a duplicate of #1422 since that one has more details (references the upstream Doxygen issue). *** This bug has been marked as a duplicate of bug 1422 ***