azu

gistfile1.txt

/Users/ranha/c_misc/souwa% gcc --version
i686-apple-darwin11-llvm-gcc-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00)
Copyright (C) 2007 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


/Users/ranha/c_misc/souwa% gcc -Wall -Wextra nyan.c
/Users/ranha/c_misc/souwa% ./a.out 
1 + 2 + 3 + 4 + 5
15

nyan.c

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

int f();
int main();

int f(void)
{
    srand(182551180);
    if((((uint64_t)main) + 13) ==
       *(((uint64_t*)__builtin_frame_address(0)) + ((5-1) * 6) + 1)){
        puts("5");
        return 5;
    }
    for(;;) {
        if((((uint64_t)main) + 13) ==
           *(((uint64_t*)__builtin_frame_address(0)) + ((rand() % 5) * 6) + 1)){
            printf("%d + ",(rand() % 5) + 1);
            return ((rand()%5) + 1) + f();/* a + bはaが先にcallされるとする */
        }
        else {
            (void)(rand()%5);
            (void)(rand()%5);
        }
    }
}

int main()
{
    printf("%d\n",f());
    return 0;
}