I could be missing something here, but in the cm3-5.2.6.ebuild's initial import, it differed from 5.2.4 by pulling in cm3-bin.
Which just seems quite odd, since A) 5.2.4 didn't have a dep on the bin, B) cm3 *should* be the src, and cm3-bin is the compiled version.
Guessing you meant !dev-lang/cm3-bin for cm3's dep, otherwise pardon the false bug .
i broke out cm3-bin from cm3 to make management easier
and that way people can emerge just cm3-bin if they want