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Re: Major gcc 4.1.1 and up security issue


From: Marcin Owsiany <marcin () owsiany pl>
Date: Mon, 22 Jan 2007 20:42:35 +0000

On Mon, Jan 22, 2007 at 02:50:21PM -0500, Valdis.Kletnieks () vt edu wrote:
It's generally considered performance-crippling
to add inline code that does a "test condition/branch" pair after *every single*
opcode that might cause an overflow - so the C paradigm is to leave them out
and have the programmer code tests when actually needed.

Right, seems that I had too much Java for too long recently - I tend to
think of terms of exceptions being thrown in such cases, not
assembly-level flag checking...

You think it's bad *now*, where you have to force-feed a 2-billion-something
value in to cause an integer overflow, you obviously aren't old enough to have
programmed on 16-bit machines, where numbers around 32,000 were sufficient,

Actually, I'm old enough to have programmed on 8-bit machines, but we're
getting off-topic here :-)

Marcin
-- 
Marcin Owsiany <marcin () owsiany pl>              http://marcin.owsiany.pl/
GnuPG: 1024D/60F41216  FE67 DA2D 0ACA FC5E 3F75  D6F6 3A0D 8AA0 60F4 1216
 
"Every program in development at MIT expands until it can read mail."
                                                              -- Unknown

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