相关疑难解决方法(0)

在C中的以下陈述中哪一个更好用？

static const int var = 5;

要么

#define var 5

要么

enum { var = 5 };

使用static constvars比#define预处理器更好吗？或者也许取决于背景？

每种方法的优点/缺点是什么？

刚刚在gdb中检查以下内容:

char *a[] = {"one","two","three","four"};
char *b[] = {"one","two","three","four"};
char *c[] = {"two","three","four","five"};
char *d[] = {"one","three","four","six"};

我得到以下内容:

(gdb) p a
$17 = {0x80961a4 "one", 0x80961a8 "two", 0x80961ac "three", 0x80961b2 "four"}
(gdb) p b
$18 = {0x80961a4 "one", 0x80961a8 "two", 0x80961ac "three", 0x80961b2 "four"}
(gdb) p c
$19 = {0x80961a8 "two", 0x80961ac "three", 0x80961b2 "four", 0x80961b7 "five"}
(gdb) p d
$20 = {0x80961a4 "one", 0x80961ac "three", 0x80961b2 "four", 0x80961bc "six"}

我真的很惊讶字符串指针对于相同的单词是相同的.我原以为每个字符串都会在堆栈上分配自己的内存,无论它是否与另一个数组中的字符串相同.

这是某种编译器优化的示例,还是这种字符串声明的标准行为？