libavcodec/utils.c:368: error: Null Dereference
  pointer `buf` last assigned on line 358 could be null and is dereferenced at line 368, column 5.

libavcodec/utils.c:351:1: start of procedure avcodec_default_release_buffer()
349. }
350. 
351. void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic){
     ^
352.     int i;
353.     InternalBuffer *buf, *last;

libavcodec/utils.c:355:5: 
353.     InternalBuffer *buf, *last;
354. 
355.     assert(pic->type==FF_BUFFER_TYPE_INTERNAL);
         ^
356.     assert(s->internal_buffer_count);
357. 

libavcodec/utils.c:356:5: 
354. 
355.     assert(pic->type==FF_BUFFER_TYPE_INTERNAL);
356.     assert(s->internal_buffer_count);
         ^
357. 
358.     buf = NULL; /* avoids warning */

libavcodec/utils.c:358:5: 
356.     assert(s->internal_buffer_count);
357. 
358.     buf = NULL; /* avoids warning */
         ^
359.     for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
360.         buf= &((InternalBuffer*)s->internal_buffer)[i];

libavcodec/utils.c:359:9: 
357. 
358.     buf = NULL; /* avoids warning */
359.     for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
             ^
360.         buf= &((InternalBuffer*)s->internal_buffer)[i];
361.         if(buf->data[0] == pic->data[0])

libavcodec/utils.c:359:14: Loop condition is false. Leaving loop
357. 
358.     buf = NULL; /* avoids warning */
359.     for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
                  ^
360.         buf= &((InternalBuffer*)s->internal_buffer)[i];
361.         if(buf->data[0] == pic->data[0])

libavcodec/utils.c:364:5: 
362.             break;
363.     }
364.     assert(i < s->internal_buffer_count);
         ^
365.     s->internal_buffer_count--;
366.     last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];

libavcodec/utils.c:365:5: 
363.     }
364.     assert(i < s->internal_buffer_count);
365.     s->internal_buffer_count--;
         ^
366.     last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
367. 

libavcodec/utils.c:366:5: 
364.     assert(i < s->internal_buffer_count);
365.     s->internal_buffer_count--;
366.     last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
         ^
367. 
368.     FFSWAP(InternalBuffer, *buf, *last);

libavcodec/utils.c:368:5: 
366.     last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
367. 
368.     FFSWAP(InternalBuffer, *buf, *last);
         ^
369. 
370.     for(i=0; i<4; i++){
