[PlanetCCRMA] libsigc++ broken?

[Fernando Pablo Lopez-Lezcano]

> Even now Tim Mayberry and I are seeing the same source code failures though.
> Wonder why it worked for you under 8.0? Different compiler?

8.0 uses gcc 3.2, 7.2/7.3 uses 2.96. I also got amSynth to build under
7.2/7.3, announcement coming in a few minutes :-)

> I'll wait for your RPMS if they are likely to be here this week.

You will have to get rid of all previous versions of gtkmm and
libsigc++, I guess. 

-- Fernando