On 23.04.2016, at 13:21, wm4 <nfx...@googlemail.com> wrote: > On Sat, 23 Apr 2016 01:16:31 +0200 > Hendrik Leppkes <h.lepp...@gmail.com> wrote: > >> On Sat, Apr 23, 2016 at 1:02 AM, Bruce Dawson >> <brucedawson-at-google....@ffmpeg.org> wrote: >>> I've noticed that when CONFIG_W64_DEMUXER is defined to zero that ffmpeg >>> compiles in a reference to ff_w64_guid_data but doesn't not link w64.o >>> (which defines that symbol). >>> >>> This normally works because most optimizers discard the reference >>> to ff_w64_guid_data early enough to not cause a linker failure. However >>> this assumption means that /Od (debug, unoptimized) and /GL (Link Time Code >>> Generation - super optimized) builds with VC++ don't work. >>> >> >> We require dead code elimination to be available in all build modes, >> therefor such build settings that do not have it are not supported. >> This is not the only place that uses this, and its a design decision >> to rely on it, therefor we won't be accepting patches to change that >> at this time, sorry. > > Why not? Someone just volunteered to cleanup this non-sense, so why not > let them?
Because it ends up with a horrible ifdef mess and also means that disabled parts will not even be checked for syntax. I.e. the reasons why we did it this way. > We may have been arguing that every compiler supports this level of > DCE, but experience has been clearly showing that this is not always the > case due to various reasons. I don't that was quite the argument. It is more a question if the rare cases are really worth the cost, especially when also the compilers could be changed to support this method of code configuration. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
