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Re: standards on SIGFPE for divide by zero



   Date: Tue, 1 Mar 2011 13:41:24 -0800
   From: Matt Thomas <jabbathespud%gmail.com@localhost>

   PowerPC cann't raise an exception on integer divide by zero.  It can
   detect it if using the divwo instruction but it still won't raise an
   exception.  Instead you need to check the OV bit in the XER register.

I see -- I assumed the question implied there was an option about
whether to deliver SIGFPE for integer division by zero on powerpc.

Delivering SIGFPE on floating-point division by zero (&c.) is perhaps
not as important, but nevertheless useful: it enables debugging high-
performance floating-point programs without recompiling them, to find
where an infinity or a NaN turned up before it has contaminated the
whole world.  So it would be good to make this work if possible.


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