ffmpeg.c:3279: error: Null Dereference
  pointer `file_oformat` last assigned on line 3268 could be null and is dereferenced at line 3279, column 17.

ffmpeg.c:3255:1: start of procedure opt_output_file()
3253. }
3254. 
3255. static void opt_output_file(const char *filename)
      ^
3256. {
3257.     AVFormatContext *oc;

ffmpeg.c:3260:5: 
3258.     int use_video, use_audio, use_subtitle;
3259.     int input_has_video, input_has_audio, input_has_subtitle;
3260.     AVFormatParameters params, *ap = &params;
          ^
3261. 
3262.     if (!strcmp(filename, "-"))

ffmpeg.c:3262:10: Taking true branch
3260.     AVFormatParameters params, *ap = &params;
3261. 
3262.     if (!strcmp(filename, "-"))
               ^
3263.         filename = "pipe:";
3264. 

ffmpeg.c:3263:9: 
3261. 
3262.     if (!strcmp(filename, "-"))
3263.         filename = "pipe:";
              ^
3264. 
3265.     oc = av_alloc_format_context();

ffmpeg.c:3265:5: 
3263.         filename = "pipe:";
3264. 
3265.     oc = av_alloc_format_context();
          ^
3266. 
3267.     if (!file_oformat) {

libavformat/options.c:75:1: start of procedure av_alloc_format_context()
  73. }
  74. 
  75. AVFormatContext *av_alloc_format_context(void)
      ^
  76. {
  77.     AVFormatContext *ic;

libavformat/options.c:78:5: 
  76. {
  77.     AVFormatContext *ic;
  78.     ic = av_malloc(sizeof(AVFormatContext));
          ^
  79.     if (!ic) return ic;
  80.     avformat_get_context_defaults(ic);

libavutil/mem.c:43:1: start of procedure av_malloc()
    41.    linker will do it automatically */
    42. 
    43. void *av_malloc(unsigned int size)
        ^
    44. {
    45.     void *ptr = NULL;

libavutil/mem.c:45:5: 
    43. void *av_malloc(unsigned int size)
    44. {
    45.     void *ptr = NULL;
            ^
    46. #ifdef CONFIG_MEMALIGN_HACK
    47.     long diff;

libavutil/mem.c:51:8: Taking false branch
    49. 
    50.     /* let's disallow possible ambiguous cases */
    51.     if(size > (INT_MAX-16) )
               ^
    52.         return NULL;
    53. 

libavutil/mem.c:62:5: Skipping posix_memalign(): method has no implementation
    60.     ((char*)ptr)[-1]= diff;
    61. #elif defined (HAVE_POSIX_MEMALIGN)
    62.     posix_memalign(&ptr,16,size);
            ^
    63. #elif defined (HAVE_MEMALIGN)
    64.     ptr = memalign(16,size);

libavutil/mem.c:94:5: 
    92.     ptr = malloc(size);
    93. #endif
    94.     return ptr;
            ^
    95. }
    96. 

libavutil/mem.c:95:1: return from a call to av_malloc
    93. #endif
    94.     return ptr;
    95. }
        ^
    96. 
    97. void *av_realloc(void *ptr, unsigned int size)

libavformat/options.c:79:10: Taking false branch
  77.     AVFormatContext *ic;
  78.     ic = av_malloc(sizeof(AVFormatContext));
  79.     if (!ic) return ic;
               ^
  80.     avformat_get_context_defaults(ic);
  81.     ic->av_class = &av_format_context_class;

libavformat/options.c:80:5: Skipping avformat_get_context_defaults(): empty list of specs
  78.     ic = av_malloc(sizeof(AVFormatContext));
  79.     if (!ic) return ic;
  80.     avformat_get_context_defaults(ic);
          ^
  81.     ic->av_class = &av_format_context_class;
  82.     return ic;

libavformat/options.c:81:5: 
  79.     if (!ic) return ic;
  80.     avformat_get_context_defaults(ic);
  81.     ic->av_class = &av_format_context_class;
          ^
  82.     return ic;
  83. }

libavformat/options.c:82:5: 
  80.     avformat_get_context_defaults(ic);
  81.     ic->av_class = &av_format_context_class;
  82.     return ic;
          ^
  83. }

libavformat/options.c:83:1: return from a call to av_alloc_format_context
  81.     ic->av_class = &av_format_context_class;
  82.     return ic;
  83. }
      ^

ffmpeg.c:3267:10: Taking true branch
3265.     oc = av_alloc_format_context();
3266. 
3267.     if (!file_oformat) {
               ^
3268.         file_oformat = guess_format(NULL, filename, NULL);
3269.         if (!file_oformat) {

ffmpeg.c:3268:9: Skipping guess_format(): empty list of specs
3266. 
3267.     if (!file_oformat) {
3268.         file_oformat = guess_format(NULL, filename, NULL);
              ^
3269.         if (!file_oformat) {
3270.             fprintf(stderr, "Unable to find a suitable output format for '%s'\n",

ffmpeg.c:3269:14: Taking true branch
3267.     if (!file_oformat) {
3268.         file_oformat = guess_format(NULL, filename, NULL);
3269.         if (!file_oformat) {
                   ^
3270.             fprintf(stderr, "Unable to find a suitable output format for '%s'\n",
3271.                     filename);

ffmpeg.c:3270:13: 
3268.         file_oformat = guess_format(NULL, filename, NULL);
3269.         if (!file_oformat) {
3270.             fprintf(stderr, "Unable to find a suitable output format for '%s'\n",
                  ^
3271.                     filename);
3272.             av_exit(1);

ffmpeg.c:3272:13: Skipping av_exit(): empty list of specs
3270.             fprintf(stderr, "Unable to find a suitable output format for '%s'\n",
3271.                     filename);
3272.             av_exit(1);
                  ^
3273.         }
3274.     }

ffmpeg.c:3276:5: 
3274.     }
3275. 
3276.     oc->oformat = file_oformat;
          ^
3277.     av_strlcpy(oc->filename, filename, sizeof(oc->filename));
3278. 

ffmpeg.c:3277:5: 
3275. 
3276.     oc->oformat = file_oformat;
3277.     av_strlcpy(oc->filename, filename, sizeof(oc->filename));
          ^
3278. 
3279.     if (!strcmp(file_oformat->name, "ffm") &&

libavutil/string.c:50:1: start of procedure av_strlcpy()
  48. }
  49. 
  50. size_t av_strlcpy(char *dst, const char *src, size_t size)
      ^
  51. {
  52.     size_t len = 0;

libavutil/string.c:52:5: 
  50. size_t av_strlcpy(char *dst, const char *src, size_t size)
  51. {
  52.     size_t len = 0;
          ^
  53.     while (++len < size && *src)
  54.         *dst++ = *src++;

libavutil/string.c:53:12: Loop condition is true. Entering loop body
  51. {
  52.     size_t len = 0;
  53.     while (++len < size && *src)
                 ^
  54.         *dst++ = *src++;
  55.     if (len <= size)

libavutil/string.c:53:28: Loop condition is false. Leaving loop
  51. {
  52.     size_t len = 0;
  53.     while (++len < size && *src)
                                 ^
  54.         *dst++ = *src++;
  55.     if (len <= size)

libavutil/string.c:55:9: Taking true branch
  53.     while (++len < size && *src)
  54.         *dst++ = *src++;
  55.     if (len <= size)
              ^
  56.         *dst = 0;
  57.     return len + strlen(src) - 1;

libavutil/string.c:56:9: 
  54.         *dst++ = *src++;
  55.     if (len <= size)
  56.         *dst = 0;
              ^
  57.     return len + strlen(src) - 1;
  58. }

libavutil/string.c:57:5: 
  55.     if (len <= size)
  56.         *dst = 0;
  57.     return len + strlen(src) - 1;
          ^
  58. }
  59. 

libavutil/string.c:58:1: return from a call to av_strlcpy
  56.         *dst = 0;
  57.     return len + strlen(src) - 1;
  58. }
      ^
  59. 
  60. size_t av_strlcat(char *dst, const char *src, size_t size)

ffmpeg.c:3279:10: 
3277.     av_strlcpy(oc->filename, filename, sizeof(oc->filename));
3278. 
3279.     if (!strcmp(file_oformat->name, "ffm") &&
               ^
3280.         av_strstart(filename, "http:", NULL)) {
3281.         /* special case for files sent to ffserver: we get the stream
