/*[XSI]*/
#if 202405L <= _POSIX_C_SOURCE
#define _XOPEN_SOURCE 800
#elif 200809L <= _POSIX_C_SOURCE
#define _XOPEN_SOURCE 700
#endif
#include <sys/shm.h>
#ifdef shmat
#undef shmat
#endif
void *(*foo)(int, const void *, int) = shmat;
int main(void) { return 0; }