Support for Sierra

[Ryan Schmidt]

On May 11, 2020, at 15:46, Dave Horsfall wrote:

> Another "port upgrade outdated", and most of the day spent compiling monster stuff such as CMAKE, LLVM, CLANG, etc.  Are these binaries no longer supported for Sierra?  I'm not sure how far I can upgrade this old MacPort Pro...

We still have build machines building for 10.6 and newer so you should generally be receiving binaries, assuming we were able to build them. All the usual restrictions apply: you must use the default prefix, default applications_dir, default frameworks_dir, default cxx_stdlib, default variants, default arch, and the ports in question must be distributable.

To the point of default variants: port maintainers sometimes change a port's default variants, but MacPorts will preserve whatever variants you had selected when you installed it. cmake, for example, switched in November to default to +python37, but if you had installed it before that time, you would have it installed with +python36 or earlier. If you upgrade, you'll have to build from source, since our binaries are only built for default variants. If you want to receive the binary, reinstall the port with its current set of default variants (e.g. run `sudo port install cmake` again).


There are reasons why some binaries might not be available for specific systems where you might otherwise expect them to be available:

* A lot of things don't build on 10.6 due to a libcxx bootstrapping issue [1] and a dependency cycle [2].

* The 10.8 builder has been offline for awhile [3] because I'm not able to reinstall Xcode completely following having to set up the builder again recently. 

* There is a 10.12-specific bug in numpy [4] that causes anything that uses numpy to fail to build in a virtual machine, such as our buildbot machines.


[1] https://trac.macports.org/ticket/59807
[2] https://trac.macports.org/ticket/60419
[3] https://trac.macports.org/ticket/60110
[4] https://trac.macports.org/ticket/59022