On Thu, 15 Aug 2013, Eric Sunshine wrote: > On Thu, Aug 15, 2013 at 5:34 PM, Stefan Beller > <stefanbeller@xxxxxxxxxxxxxx> wrote: > > When checking the previous lines in that function, we can deduce that > > hsize must always be smaller than (1u<<31), since 506049c7df2c6 > > (fix >4GiB source delta assertion failure), because entries is > > capped at an upper bound of 0xfffffffeU, so hsize contains a maximum > > value of 0x3fffffff, which is smaller than (1u<<31), so the value of > > 'i' will never be larger than 31. > > > > Signed-off-by: Stefan Beller <stefanbeller@xxxxxxxxxxxxxx> > > --- > > > > Eric, thanks for reviewing my patch. > > > > I applied the first 2 proposals (deduce, entries), but I disagree on > > the third, so I reformulated the sentence, as I really meant the variable > > i and not it as a pronoun. > > Thanks. Adding the quotes around 'i' makes your meaning clear. Without > the quotes, apparently it was ambiguous, and my brain read it as a > misspelling of 'it'. > > > Do I understand right, you're suggesting to remove the > > source code comment? I did this now, but I have a bad feeling with it. > > > > The change of this patch surely removes dead code as of now and makes it > > more readable. But also it could become alive again, once somebody > > changes things nearby and forgets about the assumption, hsize not > > exceeding a certain size. That's why I put a comment in there, so > > the future changes nearby may be more careful. > > Indeed, I feel uncomfortable with the patch in general for the very > reason that you state: it might become live again. Without the patch, > the code remains safe without any extra effort. With this patch, even > with the in-code comment, someone making changes needs to take special > care. Sometimes it makes sense to leave safeties in place, even if > they can't be triggered _today_; and safeties (such as i < 31) also > serve as documentation. That's also a valid argument. I don't think this loop is going to appear on any trace profile either. I personally have no strong opinion here. Nicolas -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html