Initialization of static variables in C

In C, static variables can only be initialized using constant literals. For example, following program fails in compilation.

#include<stdio.h>
int initializer(void)
{
    return 50;
}

int main()
{
    static int i = initializer();
    printf(" value of i = %d", i);
    getchar();
    return 0;
}

If we change the program to following, then it works without any error.

#include<stdio.h>
int main()
{
    static int i = 50;
    printf(" value of i = %d", i);
    getchar();
    return 0;
}

The reason for this is simple: All objects with static storage duration must be initialized (set to their initial values) before execution of main() starts. So a value which is not known at translation time cannot be used for initialization of static variables.

Thanks to Venki and Prateek for their contribution.

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