libavcodec/utils.c:340: error: Null Dereference
  pointer `buf` last assigned on line 330 could be null and is dereferenced at line 340, column 5.

libavcodec/utils.c:323:1: start of procedure avcodec_default_release_buffer()
321. }
322. 
323. void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic){
     ^
324.     int i;
325.     InternalBuffer *buf, *last;

libavcodec/utils.c:327:5: 
325.     InternalBuffer *buf, *last;
326. 
327.     assert(pic->type==FF_BUFFER_TYPE_INTERNAL);
         ^
328.     assert(s->internal_buffer_count);
329. 

libavcodec/utils.c:328:5: 
326. 
327.     assert(pic->type==FF_BUFFER_TYPE_INTERNAL);
328.     assert(s->internal_buffer_count);
         ^
329. 
330.     buf = NULL; /* avoids warning */

libavcodec/utils.c:330:5: 
328.     assert(s->internal_buffer_count);
329. 
330.     buf = NULL; /* avoids warning */
         ^
331.     for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
332.         buf= &((InternalBuffer*)s->internal_buffer)[i];

libavcodec/utils.c:331:9: 
329. 
330.     buf = NULL; /* avoids warning */
331.     for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
             ^
332.         buf= &((InternalBuffer*)s->internal_buffer)[i];
333.         if(buf->data[0] == pic->data[0])

libavcodec/utils.c:331:14: Loop condition is false. Leaving loop
329. 
330.     buf = NULL; /* avoids warning */
331.     for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
                  ^
332.         buf= &((InternalBuffer*)s->internal_buffer)[i];
333.         if(buf->data[0] == pic->data[0])

libavcodec/utils.c:336:5: 
334.             break;
335.     }
336.     assert(i < s->internal_buffer_count);
         ^
337.     s->internal_buffer_count--;
338.     last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];

libavcodec/utils.c:337:5: 
335.     }
336.     assert(i < s->internal_buffer_count);
337.     s->internal_buffer_count--;
         ^
338.     last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
339. 

libavcodec/utils.c:338:5: 
336.     assert(i < s->internal_buffer_count);
337.     s->internal_buffer_count--;
338.     last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
         ^
339. 
340.     FFSWAP(InternalBuffer, *buf, *last);

libavcodec/utils.c:340:5: 
338.     last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
339. 
340.     FFSWAP(InternalBuffer, *buf, *last);
         ^
341. 
342.     for(i=0; i<4; i++){
