On Wed, Oct 7, 2015 at 8:21 PM, Michael Niedermayer <mich...@niedermayer.cc> wrote: > On Wed, Oct 07, 2015 at 06:22:08PM -0400, Ganesh Ajjanagadde wrote: >> Commit 6dac8c8327 disabled av_uninit for clang, due to some useless warnings. >> The concept of av_uninit is inherently useful though. This patch silences a >> bunch of warnings on clang e.g >> http://fate.ffmpeg.org/log.cgi?time=20150918181527&log=compile&slot=x86_64-darwin-clang-polly-vectorize-stripmine-3.7. >> Furthermore, it should be useful for general usage of av_uninit in future. >> >> Signed-off-by: Ganesh Ajjanagadde <gajjanaga...@gmail.com> >> --- >> libavutil/attributes.h | 8 ++++++++ >> 1 file changed, 8 insertions(+) >> >> diff --git a/libavutil/attributes.h b/libavutil/attributes.h >> index 5c6b9de..ceb9e29 100644 >> --- a/libavutil/attributes.h >> +++ b/libavutil/attributes.h >> @@ -147,6 +147,14 @@ >> >> #if defined(__GNUC__) && !defined(__INTEL_COMPILER) && !defined(__clang__) >> # define av_uninit(x) x=x >> +#elif defined(__clang__) >> +#if __has_warning("-Wuninitialized") >> +# define av_uninit(x) \ >> + _Pragma("clang diagnostic push") \ >> + _Pragma("clang diagnostic ignored \"-Wuninitialized\"") \ >> + x=x \ >> + _Pragma("clang diagnostic pop") >> +#endif > > this breaks > make distclean ; ./configure --cc='ccache clang' && make -j12 > it does not break clang alone and clearing the ccache cache does not > help > ccache version 3.1.6 > > In file included from libavfilter/af_aecho.c:1: > libavfilter/af_aecho.c:226:315: error: expected identifier or '(' > static void echo_samples_dblp(AudioEchoContext *ctx, uint8_t **delayptrs, > uint8_t * const *src, uint8_t **dst, int nb_samples, int channels) { const > double out_gain = ctx->out_gain; const double in_gain = ctx->in_gain; const > int nb_echoes = ctx->nb_echoes; const int max_samples = ctx->max_samples; int > i, j, chan,#pragma clang diagnostic push#pragma clang diagnostic ignored > "-Wuninitialized" index=index#pragma clang diagnostic pop; ((void)0); for > (chan = 0; chan < channels; chan++) { const double *s = (double *)src[chan]; > double *d = (double *)dst[chan]; double *dbuf = (double *)delayptrs[chan]; > index = ctx->delay_index; for (i = 0; i < nb_samples; i++, s++, d++) { double > out, in; in = *s; out = in * in_gain; for (j = 0; j < nb_echoes; j++) { int > ix = index + max_samples - ctx->samples[j]; ix = (((ix) >= (max_samples)) ? > (ix) - (max_samples) : (ix)); out += dbuf[ix] * ctx->decay[j]; } out *= > out_gain; *d = av_clipd_c(out, -1.0, 1.0); dbuf[index] = in; index = (((index > + 1) >= (max_samples)) ? (index + 1) - (max_samples) : (index + 1)); } } > ctx->delay_index = index; } > > > > > ^ > > [...]
ccache and clang have some weird interaction issues -for instance a lot of -Warray-bounds are triggered for glibc functions like strcmp. I vaguely recall some suggestion to use an environment variable to avoid the breakage: http://petereisentraut.blogspot.com/2011/09/ccache-and-clang-part-2.html Anyway, this sounds like it needs to be fixed upstream with clang or ccache or possibly both. I drop this patch as infeasible at the moment; may revisit if this is sorted out upstream. > -- > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB > > When the tyrant has disposed of foreign enemies by conquest or treaty, and > there is nothing more to fear from them, then he is always stirring up > some war or other, in order that the people may require a leader. -- Plato > > _______________________________________________ > 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
