Author gvanrossum
Recipients alexandre.vassalotti, christian.heimes, gregory.p.smith, gvanrossum, loewis
Date 2008-01-09.17:29:04
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Message-id <1199899754.69.0.590809258366.issue1621@psf.upfronthosting.co.za>
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Alexandre, which Python version did you compile with -Wstrict-overflow?
 It would behoove us to check 2.5.2 thoroughly before it goes out the door.

I will contact Coverity to ask if they check for this kind of thing. 
(They just upgraded us to "Rung 2", whatever that may mean. :-)

MvL: I don't want 2s complement throughout the language, I just want the
overflow checks to be reliable.  Since I'd forgotten about the
difference between unsigned and signed overflow, I have no idea how many
overflow checks have been submitted that are relying on signed overflow;
though apparently (if the -Wstrict-overflow results can be trusted)
we're okay.

FWIW, I've heard that some commercial compilers (e.g. XLC) assume that
even *unsigned* overflow is undefined, violating the C standard.  This
would suggest that buffer overflow checks should be coded without
relying on arithmetic overflow at all.  This is possible, just a bit hairy.
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Date User Action Args
2008-01-09 17:29:14gvanrossumsetspambayes_score: 0.191237 -> 0.191237
recipients: + gvanrossum, loewis, gregory.p.smith, christian.heimes, alexandre.vassalotti
2008-01-09 17:29:14gvanrossumsetspambayes_score: 0.191237 -> 0.191237
messageid: <1199899754.69.0.590809258366.issue1621@psf.upfronthosting.co.za>
2008-01-09 17:29:05gvanrossumlinkissue1621 messages
2008-01-09 17:29:04gvanrossumcreate