[Some file] uses /usr/lib/libstdc++.6.dylib as C++ standard library although macports::cxx_stdlib is set to libc++.

[Ryan Schmidt]

When running “sudo port rev-upgrade” on Mavericks running MacPorts trunk I get lots of messages along these lines:

Warning: /opt/local/lib/libxl.dylib uses /usr/lib/libstdc++.6.dylib as C++ standard library although macports::cxx_stdlib is set to libc++.

This particular library is from the libxl port. Source code is not available; it is a commercial library distributed as a precompiled binary. I cannot change the fact that the developers have compiled this library linked against libstdc++.

I assumed all I needed to do was add this line to the Portfile to indicate that this is deliberate:

configure.cxx_stdlib libstdc++

But that doesn’t eliminate the message in rev-upgrade.