It is purely a C++ package and a part of Apache Xerces. We also package the Java version as dev-java/xerces. Firstly, it is a C++ library package so it could go in dev-cpp category. Secondly, the `-c` suffix was added IMO to differentiate between different subprojects for different languages that the project supports (C++, Java & Perl). If we were to move it to the dev-cpp category the suffix could be dropped.
The upstream project name is xerces-c. I don't see much point in this. It's a lot of churn for overlays. It could be done but what's the point?
