On Saturday 08 December 2007 02:23, John Reiser wrote: > > they treat > > the words as signed, do a subtraction, the result is treated as signed, > > and the result is checked for < 0 or > 0. > > If the subtraction overflows then it is incorrect to compare the "result" > (while forgetting about the Carry) to 0.
Hmm, yes. Wasn't there a giant storm in a teacup on the gcc list a while back about whether gcc should optimise on the basis that overflow of signed arithmetic is undefined? J ------------------------------------------------------------------------- SF.Net email is sponsored by: Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php _______________________________________________ Valgrind-developers mailing list Valgrind-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/valgrind-developers
