Heads up: Problems with parallel make

[Ken Brown]

Several of my packages that used to build fine with parallel make now 
require 'make -j1'.  Without this I either get strange errors or a hang.

I can't find any pattern to explain when the problem occurs and when it 
doesn't, but it seems to be due to a change in make, starting with 
version 4.4.  By default, make now uses a FIFO rather than a pipe in its 
jobserver implementation.  You can override this with the make flag

   --jobserver-style=pipe

In all cases where I've tried this, parallel make works again.

It wouldn't surprise me if there's a bug in Cygwin's FIFO implementation 
that's responsible for this, but I haven't yet tried to track it down.

Ken