https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70336
--- Comment #5 from Manuel López-Ibáñez <manu at gcc dot gnu.org> --- (In reply to Jakub Jelinek from comment #4) > Created attachment 38172 [details] > gcc6-pr70336.patch > > IMNSHO -Wconversion is totally useless warning, and one where if you want to > avoid "false positives", we'd need to implement full VRP in the FEs. What does VRP has to do with this case? This is just that the GCC FEs still suck by doing early folding after Clang showed almost a decade ago that early folding is evil and useless. Also current -Wconversion sucks mostly because of PR40752, which has a patch that was rejected on purist but IMHO completely non-practical reasons. Also because, despite doing useless early folding, the current folding is not powerful enough to analyse relatively simple expressions such as https://gcc.gnu.org/bugzilla/show_bug.cgi?id=38522#c3.
