I doubt this is possible, but it strikes me that a number of big ports, like clang-8.0, are actually forced in the portfile to build against libc++.
And my 10.6.8 system is configured to use stdlib=libc++. But base can't rationalize this due to I suppose lack of any data showing this is how things are set up, and so forces me to build them anyway, even though the downloaded binary would be just fine for me. Any tricky way to get around this? Rebuilding clang for a revbump takes a couple of hours at least. Best, Ken
