c - 总是检查 malloc 的内存？

Question

我经常发现自己在做以下事情(在非关键组件中):

some_small_struct *ptr=(some_small_struct *) malloc(sizeof(some_small_struct));
ptr->some_member= ...;

换句话说，我为一个小结构动态分配内存，我直接使用它而不检查 malloc 的指针。我知道程序总是有可能得不到它要求的内存(呃!)，但请考虑以下几点:

If the program can't even get some memory for a small structure off the heap, maybe there are much bigger problems looming and it doesn't matter after all.

此外，如果处理空指针会进一步加剧不稳定情况怎么办？ (例如，尝试记录条件调用更多不存在的资源等)

我的推理是否合理(足够)？

更新:

1. “safe_malloc”函数在调试时很有用，否则可能会有用
2. +X 访问可以隐藏 NULL 指针的根本原因
3. 在 Linux 上，“乐观的内存分配”可以避免出现 OOM(内存不足)情况

Answer 1

取决于平台。例如，在 Linux 上(默认情况下)检查 NULL 没有多大意义:

http://linux.die.net/man/3/malloc

By default, Linux follows an optimistic memory allocation strategy. This means that when malloc() returns non-NULL there is no guarantee that the memory really is available. This is a really bad bug. In case it turns out that the system is out of memory, one or more processes will be killed by the infamous OOM killer.