upgrading to gcc9 on SnowLeopard, and progress on upgrading gcc on PowerPC and Leopard Intel

[kencu (Ken)]

It's been two years since I last worked on this much, so I thought it would be time to try to bring the older systems up to harmony, as much as possible. This has been met with some success.

With a very minor patch that looks completely upstreamable, gcc9 and libgcc9 build nicely on 10.6.8, both i386 and x86_64.

There was a hiccup six months ago when the assembler defaulted to an older version that ran into some troubles compiling i386 code 58493 but all the new default compiler updates that came along with MacPorts 2.6.x have fixed that up nicely, and there is no longer such an issue.

gcc9 passes it's test suites reasonably well if not perfectly well -- that's as good as gcc8 did, and it's performed well.

I will attach the test suite runs on i386 and x86_64 for anyone interested.

I haven't yet looked at 10.5 Intel Leopard. Given the results in this ticket, it may very well also be able to jump up to libgcc9/gcc9.

On PowerPC, gcc8/libgcc8 now build through to completion -- I have the test suites running on both Tiger and Leopard. I have not as yet tried building gcc9/libgcc9 on PowerPC.