On Sat, Oct 13, 2012 at 5:14 AM, Chris Lattner <[email protected]> wrote: > > On Oct 12, 2012, at 11:10 AM, Richard Trieu <[email protected]> wrote: > > On Fri, Oct 12, 2012 at 9:55 AM, Sean Silva <[email protected]> wrote: >> >> How many lines of code have you compiled with this warning enabled? > > Millions. >> >> How many bugs did it catch? > > Hundreds. >> >> How many false positives did it have? > > I have only checked a few dozen so far. No false positives so far. > > > This makes sense to me, use of a < comparison on a bool isn't something a > "normal" person would write :)
I've seen bool < bool comparisons in operator< implementations (during investigations for http://llvm.org/bugs/show_bug.cgi?id=13540 , which is somewhat related to rtrieu's patch). > > -Chris > > Of course, there's some code like r165811 and r165812 that I just fixed, > which technically works properly, but could be written in a different way. >> >> >> -- Sean Silva >> >> On Fri, Oct 12, 2012 at 12:38 PM, Richard Trieu <[email protected]> wrote: >> > This patch is for a new warning to Clang, called -Wlogical-not-compare. >> > It >> > is designed to catch the case where the user is attempting to negate a >> > comparison, but only manages to negate the LHS because of missing >> > parens. >> > For instance, warn here: >> > >> > if (!x < 5) >> > >> > The user probably meant: >> > >> > if (!(x < 5)) >> > >> > or >> > >> > if (x >= 5) >> > >> > When emitted, the warning will have a note suggesting this as a fix-it >> > (drop >> > the not and inverting the comparison operator). >> > >> > Also, a second note will be offer parenthesis around the LHS to silence >> > this >> > warning. >> > >> > if ((!x) < 5) >> > >> > This will not warn. >> > >> > _______________________________________________ >> > cfe-commits mailing list >> > [email protected] >> > http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits >> > > > > _______________________________________________ > cfe-commits mailing list > [email protected] > http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits > > > > _______________________________________________ > cfe-commits mailing list > [email protected] > http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits > _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
