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From: dewar@gnat.com
To: dewar@gnat.com, jbuck@synopsys.COM
Subject: Re: [PATCH] C undefined behavior fix
Cc: gcc@gcc.gnu.org, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.linuxppc.org, paulus@samba.org,
        trini@kernel.crashing.org, velco@fadata.bg
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Date: Wed,  2 Jan 2002 19:12:41 -0500 (EST)
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<<This is a modification to gcc that implements pointers as triples.
While there is a performance penalty for doing this, it can completely
eliminate the problem of exploitable buffer overflows.  However, programs
that violate the rules of ISO C by generating out-of-range pointers will
fail.
>>

Note incidentally that the C rules that allow referencing the address just
past the end of an array (an irregularity that recognizes the infeasibility
of declaring the common idiom for (a=b;a<&b[10];a++)) has an interesting
consequence on a segmented machine, namely that you cannot allocate an
array too near the end of the segment.
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