An example code described in "21st Century C" that rewrites the value of a const variable.

RewritingConstVar.c

#include <stdio.h>

int main(void) {
	int *a;
	const int **b = &a;
	const int c = 1;
	printf("c = %d\n", c); // c = 1

	*b = &c;
	*a = 2;
	printf("c = %d\n", c); // c = 2

	return 0;
}

https://ideone.com/qk4Pnj