Both were added in 12/2008, at a time when the choice of SCons still had
to be defended, and neither was ever used in practice.
The MD5 based change detection of SCons, in concert with the declarative
build dependency tree alleviates the need for "cleaning paranoia" and makes
full rebuilds a rare event.
Beyond being unused, both tool integrations require to rewrite the `$CXX`
construction variable into "wrapper g++", which silently changes what any
tool reading the build commands concludes about the compiler in use. That
matters for the compilation database, which needs to be added next.