This bug is essentially similar to bug reported on FL-295. Upon further research I am beginning to understand the problem. I think it is due to poorly written code that assumes links and those linking mechanisms have been changed a couple of years ago. It is discussed at http://fedoraproject.org/wiki/UnderstandingDSOLinkChange
and other places. Over my head, but I got the idea enough. In this case I added (temporarily) LDFLAGS='-Wl,-lm,-ldl' to /etc/portage/make.conf. The -ldl was added after 1st failure run with make.conf modification as I then received a similar error but this time referring to libdl. It then installs without incident. A patch would be a better fix.