src/http/ngx_http_file_cache.c:984: error: Integer Overflow L1
  (0 - 1):unsigned32.

src/http/ngx_http_file_cache.c:982:5: <LHS trace>
980.     cache = c->file_cache;
981. 
982.     ngx_shmtx_lock(&cache->shpool->mutex);
         ^
983. 
984.     c->node->count--;

src/http/ngx_http_file_cache.c:982:5: Call
980.     cache = c->file_cache;
981. 
982.     ngx_shmtx_lock(&cache->shpool->mutex);
         ^
983. 
984.     c->node->count--;

src/core/ngx_spinlock.c:11:1: Parameter `*lock`
   9. 
  10. 
  11. void
      ^
  12. ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin)
  13. {

src/http/ngx_http_file_cache.c:984:5: Binary operation: (0 - 1):unsigned32
982.     ngx_shmtx_lock(&cache->shpool->mutex);
983. 
984.     c->node->count--;
         ^
985. 
986.     ngx_shmtx_unlock(&cache->shpool->mutex);
