How can I stringify a macro using a macro?

Question

#define A_1 {2,1124,124110,2,0,20,5121,0,21241,10}
#define SFY(macro) #macro

void func(char* s, int i) {
    printf("%d %s", i, s);
}

int main (void) {
    int a[10] = A_1;
    func(SFY(A_1), 2);
}

My desired output of this would be:

2 {2,1124,124110,2,0,20,5121,0,21241,10}

How can I stringify a macro like this?

Answer 1

You need to add one more layer of indirection in order to expand the macro (and since it contains commas, you must go variadic):

#define A_1 {2,1124,124110,2,0,20,5121,0,21241,10}
#define SFY_2(...) #__VA_ARGS__
#define SFY(macro) SFY_2(macro)

void func(char* s, int i) {
    printf("%d %s", i, s);
}

int main (void) {
    int a[10] = A_1;
    func(SFY(A_1), 2);
}

[Live example]