I started a large build, then hit ^Z.  Then "fg", and this is what happened:

--------begin------------
make[2]: Leaving directory `/c/base2/node/comp/DiagNodeScheduler'
make[2]: Entering directory `/c/base2/node/comp/equipConf'

[1]+  Stopped                 nice -20 make -rsw -C pload/SCC target
/c/base2/node> fg
nice -20 make -rsw -C pload/SCC target
assertion "hsig_inited" failed: file 
"/netrel/src/cygwin-snapshot-20030908-1/winsup/cygwin/sigproc.cc", line 204
Signal 6
make[1]: *** [__build__equipConf] Interrupt
make: *** [bsp-CC8260] Interrupt

-----------end-------------

After the "Signal 6" line, some process (I killed it before finding out 
exactly which process) was using 100% of the CPU until I hit ^C.

I have been unable to reproduce the problem.  But, in my attempts, I 
found a couple of other issuses.  I should mention here that this build 
system spends most of it's time running non-cygwin programs.

If I hit ^Z while a non-cygwin process is running, there seems to be 
about a 50% chance of everything working as expected:
   - after non-cygwin process finishes, return to shell, can rusume make 
with fg.


But, the other 50% of the time, the cygwin processes stop, but the shell 
does not present a prompt again.  (running kill -CONT <make-proc> 
<sh-proc> rusumes the build).