On Sun, 25 Oct 2015 12:39:08 +0100 Nicolas George <geo...@nsup.org> wrote:
> Le quartidi 4 brumaire, an CCXXIV, Derek Buitenhuis a écrit : > > Perhaps wm4 or Michael or someone can chime in... I don't know of a single > > good > > way to handle this. Just failing if the locale has a radix point as a comma > > instead > > of a period seems less bad than mucking with the thread/process locale > > inside a > > library. > > Personally, I consider that users setting locale variables other than > LC_CTYPE and LC_MESSAGES mean literally "please break random programs on my > system"; I am convinced of this since more than fifteen years when initing > Gtk in the OCaml toplevel would cause "let pi = 3.14" to set pi to 3.0. Well, I'm not sure if this only affects LC_NUMERIC and maybe LC_COLLATE? On the other hand, setting LC_CTYPE could have some bad effects too. > Therefore, my opinion on this is: let us document that for all FFmpeg > libraries, setting any locale except these two to anything other than > C/POSIX yields undefined behaviours. I'd be fine with that, but then we should maybe check the current locale for sanity at certain points, and raise a clear error if it's broken. Many programs set locale by default, including GUI toolkits like Qt (!). Qt in particular document this explicitly: http://doc.qt.io/qt-5/qcoreapplication.html#locale-settings So we shouldn't silently break everything. But again, breaking loudly is ok IMHO. > If people want to write applications using various locales, they should use > the version with explicit locale argument introduced in the latest version > of the standard. You could demand the same from FFmpeg. It's impractical because not all systems support these functions. PS: I think we don't need to block the patch on this issue anymore, because: 1. We don't have any workarounds in place this patch could use, 2. Lots of other code is probably affected anyway _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
