> On Oct 20, 2017, at 20:32, Ken Cunningham <[email protected]> > wrote: > > > >> On Oct 20, 2017, at 7:39 PM, Ryan Schmidt <[email protected]> wrote: >> >> I guess my question was: is there something unique about ffmpeg that makes >> it require gcc6 on PowerPC, as opposed to one of the alternatives MacPorts >> would choose, or is MacPorts choosing inappropriate alternatives for all >> ports on PowerPC? If the latter, the fix should be in base, not in >> individual ports. >> > > The latter. MacPorts is in almost all cases choosing inappropriate > alternatives for PowerPC. > > On PPC, the compiler should default to gcc42 (whichever flavour - there are a > couple of different variants of that - apple-gcc42 or gcc42 are for all > intents and purposes the same compiler for our purposes). If *gcc42 is > blacklisted, MacPorts should then go to gcc6.
The issue in doing that is that C++ ports will possibly be build inconsistently because macports-gcc6 will use the MacPorts-provided runtimes from libgcc which are not compatible with the host's libstdc++ (used by gcc42). If you want to use gcc6 for a full build of MacPorts on ppc, I'd suggest doing something similar to the bootstrapping I documented for modern clang/libc++ on Leopard and Snow Leopard (and please document it for future users). > There should be no other choices unless something is explicitly whitelisted > (like gcc5 for pdftk). > > If you know how to make this happen, that would be great! > > [aside — that actually won’t fix quite a few ports, which just blacklist > *gcc* — that has to be undone on PPC all the time, as it is inappropriate for > PPC to do that.] > > Ken
