[FFmpeg-devel] [PATCH 0/8] replacing #define by typedef

Ganesh Ajjanagadde gajjanagadde at gmail.com
Thu Nov 19 14:14:07 CET 2015

#define is often abused for doing typedefs. Usually there is no issue, but the
usage is unnecessarily risky and should be avoided. Concrete example taken from
typedef int* int_p1;
int_p1 a, b, c; // a, b, c are all pointers to int
#define int_p2 int*
int_p2 a, b, c; // only first is a pointer!

Furthermore, there is an additional advantage in that typedef respects scoping
rules while #define needs a matching undef or else is valid till the end of the
file. This simplifies slightly tests/tiny_ssim.

This series removes all such abuses of the preprocessor in FFmpeg.

Ganesh Ajjanagadde (8):
  avcodec/lpc: replace #define by typedef
  avcodec/aac_defines: replace #define by typedef
  avcodec/ac3: replace #define by typedef
  avcodec/aacps_tablegen_template: replace #define by typedef
  avcodec/amr: replace #define by typedef
  tests/tiny_ssim: replace #define by typedef
  avcodec/faanidct: replace #define by typedef
  avcodec/resample2: replace #define by typedef

 libavcodec/aac_defines.h             | 20 ++++++++++----------
 libavcodec/aacps_tablegen_template.c |  4 ++--
 libavcodec/ac3.h                     |  8 ++++----
 libavcodec/amr.h                     |  4 ++--
 libavcodec/faanidct.c                |  2 +-
 libavcodec/lpc.h                     |  6 +++---
 libavcodec/resample2.c               | 12 ++++++------
 tests/tiny_ssim.c                    |  5 ++---
 8 files changed, 30 insertions(+), 31 deletions(-)


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