On 09/26/2013 06:02 PM, Vincent Lefevre wrote: > On 2013-09-26 15:49:05 +0100, Andrew Haley wrote: >> On 09/26/2013 09:29 AM, Vincent Lefevre wrote: >>> On 2013-09-25 22:29:58 -0400, James K. Lowden wrote: >>>> You mean that a naïve rendering of the source code implies an overflow >>>> where none might exist in the actual emitted object code. And, >>>> presumably, the converse: that even if the source is written such that >>>> there logically can't be an overflow, the compiler might render object >>>> code that does. >>> >>> The converse is forbidden. >> >> You'll find it hard to justify that by any language in the standard. > > What do you mean? There is no reason why a compiler should not generate an overflow where none is written in the program, as long as it doesn't generate a different result. Andrew.
