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++){

void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic){
    int i;
    InternalBuffer *buf, *last;
    assert(pic->type==FF_BUFFER_TYPE_INTERNAL);
    assert(s->internal_buffer_count);
    buf = NULL;
    for(i=0; i<s->internal_buffer_count; i++){
        buf= &((InternalBuffer*)s->internal_buffer)[i];
        if(buf->data[0] == pic->data[0])
            break;
    }
    assert(i < s->internal_buffer_count);
    s->internal_buffer_count--;
    last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
    FFSWAP(InternalBuffer, *buf, *last);
    for(i=0; i<4; i++){
        pic->data[i]=NULL;
    }
    if(s->debug&FF_DEBUG_BUFFERS)
        av_log(s, AV_LOG_DEBUG, "default_release_buffer called on pic %p, %d buffers used\n", pic, s->internal_buffer_count);
}
['void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic){\n    int i;\n    InternalBuffer *buf, *last;\n    assert(pic->type==FF_BUFFER_TYPE_INTERNAL);\n    assert(s->internal_buffer_count);\n    buf = NULL;\n    for(i=0; i<s->internal_buffer_count; i++){\n        buf= &((InternalBuffer*)s->internal_buffer)[i];\n        if(buf->data[0] == pic->data[0])\n            break;\n    }\n    assert(i < s->internal_buffer_count);\n    s->internal_buffer_count--;\n    last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];\n    FFSWAP(InternalBuffer, *buf, *last);\n    for(i=0; i<4; i++){\n        pic->data[i]=NULL;\n    }\n    if(s->debug&FF_DEBUG_BUFFERS)\n        av_log(s, AV_LOG_DEBUG, "default_release_buffer called on pic %p, %d buffers used\\n", pic, s->internal_buffer_count);\n}']