Slight change of subject ...
All this arguing has been about the value of spawn as a speed enhancement:
Pro: spawn is way faster!
Con: but it may destabilize things - we'll stick with slow-but-stable fork.
Which ignores the fact that Cygwin fork is *not* that stable. In our experience make -jN results in frequent failed builds due to fork failures. Thus it seems to me that
Pro: spawn doesn't suffer from the documented problems which result from trying to emulate fork on Windows.
should be part of the conversation too.
-David Boyce