Tuesday, December 1, 2009

Bouquet of questions-3

o How can you add attributes in gcc, e.g., changing function call way from cdecl to stdcall?

GCC allows you to attribute your functions with __attribute__ macro.
This macro allows you to write more readable, clean code. I liked,

- __attribute__((destructor))
- __attribute__((constructor))
- __attribute__((warning("Function definition is not found)))

There are plenty of them, check them out at: http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html

o What does following code do?

int flag = 2;
int (*fp)(void) __attribute__((cdecl));
void fun() __attribute__((warning("No definition")));
int main(void)
fp = main;
while(flag--) {
int x = (*fp)();

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