C:在传递给函数时将void*赋值给它自己

LZMA SDK 源代码,并注意到它们将传递到方法中的指针分配给自己-示例(来自SDK,C/Util/7z/7zAlloc.C):

void *SzAlloc(void *p, size_t size)
{
  p = p;     <-- !
  if (size == 0)
    return 0;
  #ifdef _SZ_ALLOC_DEBUG
  fprintf(stderr, "\nAlloc %10d bytes; count = %10d", size, g_allocCount);
  g_allocCount++;
  #endif
  return malloc(size);
}