为什么 C/C++ 中没有一位数据类型？
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Why there isn't a single bit data type in C/C++?
提问by iloahz
For bool, it's 8 bit while has only true and false, why don't they make it single bit.
对于bool，它是 8 位，而只有 true 和 false，他们为什么不将其设为一位。
And I know there's bitset, however it's not that convenient, and I just wonder why?
而且我知道有bitset，但是它不是那么方便，我只是想知道为什么？
回答by Igor Popov
The basic data structure at the hardware level of mainstream CPUs is a byte. Operating on bits in these CPUs require additional processing, i.e. some CPU time.
The same holds for bitset.
主流CPU在硬件层面的基本数据结构是一个字节。对这些 CPU 中的位进行操作需要额外的处理，即一些 CPU 时间。这同样适用于bitset。
回答by Albert
Not exactly an answer to why there is not a native type. But you can get a 1-bit type inside of a struct like this:
不完全是为什么没有本机类型的答案。但是你可以在结构中得到一个 1 位类型，如下所示：
struct A {
int a : 1; // 1 bit wide
int b : 1;
int c : 2; // 2 bits
int d : 4; // 4 bits
};
Thus, sizeof(A) == 1could be if there wouldn't be the padding (which probably takes it to a multiple of sizeof(void*), i.e. maybe 4 for 32bit systems).
因此，sizeof(A) == 1如果没有填充（这可能是 的倍数sizeof(void*)，即对于 32 位系统，可能是 4）。
Note that you cannot get a pointer to any of these fields because of the reasons stated by the other people. That might also be why there does not exist a native type.
请注意，由于其他人陈述的原因，您无法获得指向任何这些字段的指针。这也可能是不存在本机类型的原因。
