When initializing an array, can variables be inside braces?

I am new to C and have found that it is common to initialize arrays with constants. I’m curious, is the following code legal?

int a = 1;
int b = 2;
int c = 3;
int array[3] = {a, b, c};

>Solution :

It depends on the lifetime of the variables.

If they are static variables, the initializer must be constant.

int a = 1;
int b = 2;
int c = 3;
int array[] = { a, b, c };   // XXX Error

int main( void ) {
}

const int a = 1;
const int b = 2;
const int c = 3;
int array[] = { a, b, c };   // ok

int main( void ) {
}

If they are automatic variables, this is allowed.

int main( void ) {
   int a = 1;
   int b = 2;
   int c = 3;
   int array[] = { a, b, c };   // ok
}

C23 §6.7.11 ¶5 All the expressions in an initializer for an object that has static or thread storage duration or is declared with the constexpr storage-class specifier shall be constant expressions or string literals