ffmpeg | branch: release/2.4 | Michael Niedermayer <mich...@niedermayer.cc> | Thu Sep 3 02:17:24 2015 +0200| [c09fe0346d9456a47717ebbd48bee1e62cab6818] | committer: Michael Niedermayer
avutil/common: Add FFNABS() This macro avoids the undefined corner case with the *_MIN values Previous version Reviewed-by: Ganesh Ajjanagadde <gajja...@mit.edu> Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> (cherry picked from commit d6cd614dac579850076ae312c29c4188f8659e46) Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c09fe0346d9456a47717ebbd48bee1e62cab6818 --- libavutil/common.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/libavutil/common.h b/libavutil/common.h index a48959d..526f5c6 100644 --- a/libavutil/common.h +++ b/libavutil/common.h @@ -63,10 +63,19 @@ * Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they * are not representable as absolute values of their type. This is the same * as with *abs() + * @see FFNABS() */ #define FFABS(a) ((a) >= 0 ? (a) : (-(a))) #define FFSIGN(a) ((a) > 0 ? 1 : -1) +/** + * Negative Absolute value. + * this works for all integers of all types. + * As with many macros, this evaluates its argument twice, it thus must not have + * a sideeffect, that is FFNABS(x++) has undefined behavior. + */ +#define FFNABS(a) ((a) <= 0 ? (a) : (-(a))) + #define FFMAX(a,b) ((a) > (b) ? (a) : (b)) #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c) #define FFMIN(a,b) ((a) > (b) ? (b) : (a)) _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
