In C, static variables can only be initialized using constant literals. For example, following program fails in compilation.
If we change the program to following, then it works without any error.
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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