ffmpeg.c:3304: error: Null Dereference
  pointer `file_oformat` last assigned on line 3293 could be null and is dereferenced at line 3304, column 17.

ffmpeg.c:3280:1: start of procedure opt_output_file()
3278. }
3279. 
3280. static void opt_output_file(const char *filename)
      ^
3281. {
3282.     AVFormatContext *oc;

ffmpeg.c:3285:5: 
3283.     int use_video, use_audio, use_subtitle;
3284.     int input_has_video, input_has_audio, input_has_subtitle;
3285.     AVFormatParameters params, *ap = &params;
          ^
3286. 
3287.     if (!strcmp(filename, "-"))

ffmpeg.c:3287:10: Taking false branch
3285.     AVFormatParameters params, *ap = &params;
3286. 
3287.     if (!strcmp(filename, "-"))
               ^
3288.         filename = "pipe:";
3289. 

ffmpeg.c:3290:5: 
3288.         filename = "pipe:";
3289. 
3290.     oc = av_alloc_format_context();
          ^
3291. 
3292.     if (!file_oformat) {

libavformat/utils.c:430:1: start of procedure av_alloc_format_context()
  428. }
  429. 
  430. AVFormatContext *av_alloc_format_context(void)
       ^
  431. {
  432.     AVFormatContext *ic;

libavformat/utils.c:433:5: 
  431. {
  432.     AVFormatContext *ic;
  433.     ic = av_malloc(sizeof(AVFormatContext));
           ^
  434.     if (!ic) return ic;
  435.     avformat_get_context_defaults(ic);

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

libavutil/mem.c:50:8: Taking false branch
    48. 
    49.     /* let's disallow possible ambiguous cases */
    50.     if(size > (INT_MAX-16) )
               ^
    51.         return NULL;
    52. 

libavutil/mem.c:61:5: Skipping memalign(): method has no implementation
    59.     ((char*)ptr)[-1]= diff;
    60. #elif defined (HAVE_MEMALIGN)
    61.     ptr = memalign(16,size);
            ^
    62.     /* Why 64?
    63.        Indeed, we should align it:

libavutil/mem.c:91:5: 
    89.     ptr = malloc(size);
    90. #endif
    91.     return ptr;
            ^
    92. }
    93. 

libavutil/mem.c:92:1: return from a call to av_malloc
    90. #endif
    91.     return ptr;
    92. }
        ^
    93. 
    94. void *av_realloc(void *ptr, unsigned int size)

libavformat/utils.c:434:10: Taking false branch
  432.     AVFormatContext *ic;
  433.     ic = av_malloc(sizeof(AVFormatContext));
  434.     if (!ic) return ic;
                ^
  435.     avformat_get_context_defaults(ic);
  436.     ic->av_class = &av_format_context_class;

libavformat/utils.c:435:5: Skipping avformat_get_context_defaults(): empty list of specs
  433.     ic = av_malloc(sizeof(AVFormatContext));
  434.     if (!ic) return ic;
  435.     avformat_get_context_defaults(ic);
           ^
  436.     ic->av_class = &av_format_context_class;
  437.     return ic;

libavformat/utils.c:436:5: 
  434.     if (!ic) return ic;
  435.     avformat_get_context_defaults(ic);
  436.     ic->av_class = &av_format_context_class;
           ^
  437.     return ic;
  438. }

libavformat/utils.c:437:5: 
  435.     avformat_get_context_defaults(ic);
  436.     ic->av_class = &av_format_context_class;
  437.     return ic;
           ^
  438. }
  439. 

libavformat/utils.c:438:1: return from a call to av_alloc_format_context
  436.     ic->av_class = &av_format_context_class;
  437.     return ic;
  438. }
       ^
  439. 
  440. int av_open_input_stream(AVFormatContext **ic_ptr,

ffmpeg.c:3292:10: Taking true branch
3290.     oc = av_alloc_format_context();
3291. 
3292.     if (!file_oformat) {
               ^
3293.         file_oformat = guess_format(NULL, filename, NULL);
3294.         if (!file_oformat) {

ffmpeg.c:3293:9: Skipping guess_format(): empty list of specs
3291. 
3292.     if (!file_oformat) {
3293.         file_oformat = guess_format(NULL, filename, NULL);
              ^
3294.         if (!file_oformat) {
3295.             fprintf(stderr, "Unable to find a suitable output format for '%s'\n",

ffmpeg.c:3294:14: Taking true branch
3292.     if (!file_oformat) {
3293.         file_oformat = guess_format(NULL, filename, NULL);
3294.         if (!file_oformat) {
                   ^
3295.             fprintf(stderr, "Unable to find a suitable output format for '%s'\n",
3296.                     filename);

ffmpeg.c:3295:13: 
3293.         file_oformat = guess_format(NULL, filename, NULL);
3294.         if (!file_oformat) {
3295.             fprintf(stderr, "Unable to find a suitable output format for '%s'\n",
                  ^
3296.                     filename);
3297.             av_exit(1);

ffmpeg.c:3297:13: Skipping av_exit(): empty list of specs
3295.             fprintf(stderr, "Unable to find a suitable output format for '%s'\n",
3296.                     filename);
3297.             av_exit(1);
                  ^
3298.         }
3299.     }

ffmpeg.c:3301:5: 
3299.     }
3300. 
3301.     oc->oformat = file_oformat;
          ^
3302.     av_strlcpy(oc->filename, filename, sizeof(oc->filename));
3303. 

ffmpeg.c:3302:5: 
3300. 
3301.     oc->oformat = file_oformat;
3302.     av_strlcpy(oc->filename, filename, sizeof(oc->filename));
          ^
3303. 
3304.     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:3304:10: 
3302.     av_strlcpy(oc->filename, filename, sizeof(oc->filename));
3303. 
3304.     if (!strcmp(file_oformat->name, "ffm") &&
               ^
3305.         av_strstart(filename, "http:", NULL)) {
3306.         /* special case for files sent to ffserver: we get the stream
