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

[Andrew Macleod]

>> > 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 ... 

Yes, and I'll be checking in the final version of the patch soon. While
making the flowgraph correct, I decided I might as well go all out and
add the code required to correctly build a flow graph with the
REG_EH_REGION and REG_EH_RETHROW notes. Currently its incorrect, but
doesn't show up much unless you're using -fnew-exceptions.

Andrew