#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

// GCC ERROR:  assignment of read-only location ‘*a_n’

void print_number_by_address(const int* a_n) {
    printf("*a_n = %d\n", *a_n);

    // Mischief
    *a_n = 999;  // assignment of read-only location ‘*a_n’
/*
    k.c: In function ‘print_number_by_address’:
    k.c:10:7: error: assignment of read-only location ‘*a_n’
      *a_n = 999;  // assignment of read-only location ‘*a_n’
           ^
*/
}

int main(int argc, char* argv[]) {
    int n = 5;
    print_number_by_address(&n);
    return EXIT_SUCCESS;
}
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