Can't compile `lilypond-devel`

[Mojca Miklavec]

On Mon, 2 Sep 2019 at 15:18, Ken Cunningham wrote:
>
> It's correct base behavior. Base sees a port compiled against libstdc++ on a system configured to use libc++, and knows this is most often bad, and needs to be fixed. So it flags this as an error.
>
> If the portfile author investigates and works out that it's OK for this port to do that (as it doesn't use with any other c++ libraries or provide any for other ports to use) then that "error"  can be overridden by forcing the configure.cxx_stdlib in the portfile, and base will stop flagging it.

I tend to disagree.

Shouldn't base be able to distinguish between the system libstdc++ and
the one from gcc shipped by MacPorts?
Why would the base want to rebuild ports that were built with gcc?

Also, assume that a port allows compilation with both MacPorts gcc, as
well as one of the newer clangs. In that case it's impossible to
hardcode the stdlib. It could also be that a particular port was built
with gcc based on user (who knows what he's doing) request. Rebuilding
those ports would be undesired.

Mojca