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From: Andrew Haley <aph@redhat.com>
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Date: Thu, 13 Feb 2003 18:44:00 -0000
To: Roger Sayle <roger@www.eyesopen.com>
Cc: Richard Henderson <rth@redhat.com>, gcc-patches@gcc.gnu.org,
	<gcc@gcc.gnu.org>
Subject: Re: [PATCH] Document arithmetic overflow semantics
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Roger Sayle writes:
 > 
 > 
 > Do you believe the Java front-end is currently incorrect to use
 > PLUS_EXPR to represent signed addition?

It probably is.  

Java requires strict 32-bit two's complement arithmetic for its ints,
and PLUS_EXPR isn't guaranteed to do that.  We could, of course,
generate something like

   uint((ulong)a + (ulong)b)

which would be well defined. 

Andrew.