c++ opnewnt hang in sched.c with sjlj EH, -g -O2

[Mumit Khan]

I had written:
> 
> Sometime between 4/17 and now, schedule_block() went into an infinite
> loop when trying to build opnewnt on x86 using sjlj EH and `-g -O2'.
> 
> Must use ``-fsjlj-exceptions -g -O2'' to tickle the bug.
> 
> I can reproduce the problem on at least 3 different x86 targets running
> Linux/glibc2 and some variant of Windows32.

Just so I don't waste others' time, this is the same problem reported
by Robert Lipe and Donn Terry (Apr 19):

   Linkname: Re: cc1plus (sjlj eh) bootstrap hangs in sched.c
   URL: http://egcs.cygnus.com/ml/egcs-bugs/1999-04/msg00525.html

which includes a patch from Andrew Macleod to flow.c that allows the
bootstrap to complete. Regression testsuite still running ... 

Regards,
Mumit