Therefore, I don't feel your patch as is is ready for inclusion — much more work needed.
Fine.
So I update my toplevel "run" script (attached) to make a separate asdf/ directory for each OS, thereby keeping things entirely partitioned but allowing to run the same toplevel script everywhere.
This "run" script does an
rsync -aL --delete
in order to clone the asdf/ directory to the os-specific one, so it has the effect of starting with a fresh asdf directory every time (i.e. with the build/ directory cleared out).
Also attached is another patch which protects the test-multiple.script from failure when the filesystem does not support symbolic links (e.g. in a virtualbox guest folder shared from the virtualbox host). This patch also adds the ability to set an ALLEGRO_NOISY environment variable so that Allegro on Windows will pop up the consoles (useful for cases when there are failures and you need to be able to capture the output).
I am reliably replicating test-encoding.script failures now with alisp8 and mlisp8 on Windows and Linux. I will send that output separately.
I am also still getting intermittent test-stamp-propagation failures, but these seem to be more rare since I am starting with clean asdf directory for each set of test runs. But the next time I do get one I will provide the output.