c - 为什么 char *s = "string"在不是 const 时不显示错误或警告

Question

下一行

char *s = "string";

即使使用 -Wall 也不会在 gcc 上抛出任何警告/错误。

AFAIK，指针 s 直接指向 .rodata 的某个部分，使其成为指向 const char.

那么，为什么指针不提示并期待:

const char *s = "string";

加:不管怎样，使用后者是更好的做法吗？

Answer 1

来自 gcc 编译选项:

-Wwrite-strings When compiling C, give string constants the type const char[length] so that copying the address of one into a non-const char * pointer produces a warning. These warnings help you find at compile time code that can try to write into a string constant, but only if you have been very careful about using const in declarations and prototypes. Otherwise, it is just a nuisance. This is why we did not make -Wall request these warnings.

所以显然您需要明确允许 -Wwrite-strings，而 Wall 不包含它。