H. S. Teoh:
The problem with that, is that Phobos often doesn't even
compile with
the previous release of DMD (or, for that matter, a commit
prior to a PR
that spans both dmd and Phobos), so it's anyone's guess what an
older
version of Phobos would do when compiled with a newer compiler.
Unless, of course, you maintain the old version enough to keep
it
compilable with the current compiler. But that's a lot of
additional
maintenance work.
The point of my answer is that I think the problem raised by
Walter can't be solved by Phobos/dmd developers. And at the
current state of D development trying to solve it will cause more
problems (and more wasted efforts) than it can solve.
Bye,
bearophile