On Thu, Dec 24, 2015 at 8:37 AM, Ronald S. Bultje <rsbul...@gmail.com> wrote: > Hi, > > On Wed, Dec 23, 2015 at 7:49 PM, Ganesh Ajjanagadde <gajja...@mit.edu> > wrote: > >> What I meant was the following (I casually labelled it as ifdef, I >> meant some preprocessor stuff): >> #if !HAVE_EXP10 || !(defined(_GNU_SOURCE)) >> ... >> #endif >> >> I have reproduced your issues via a minimal configure line, and the >> above idea fixes those. Do you see any issues? Of course, there is the >> theoretical one of a libc (more precisely libm) having exp10 without >> GNU_SOURCE, but in that case it should just use the fallback. > > > I don't like this as much. In all other instances of any other function > whatsoever, we just check if the function exists. We should do the same > thing here. If implemented correctly in configure, #if !HAVE_EXP10 should > always work. If we can fail to compile when compiling some video filter, we > can fail alike when testing for the feature in configure.
It is not easy to do via configure, as Michael points out since GNU_SOURCE may get enabled from pkg-config and other steps in configure. Basically then this will need to be deferred to a stage way below in configure, once all cflags have been set to their values. This will add IMHO greater complexity to configure than the ugly hack above. Ultimately, it is a question of which one is preferred. If you still feel this way, I will delve a bit into configure to see what can be done. > > Ronald > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
