Exercise 6.53

[ElevenZwei]

Exercise information

Exercise 6.53

Explain the effect of the second declaration in each one of the following sets of declarations. Indicate which, if any, are illegal.
(C)
int calc(char*, char*);
int calc(char* const, char* const);

Question or Bug

Answer is "illegal" in https://github.com/pezy/CppPrimer/blob/master/ch06/README.md#exercise-653 .
But I think the second one is a legal redeclaration. Compiler treats them as one function. It will not make any warning as long as they don't have their own definitions which will trigger a redefinition error.

Your enviroment information

Tested on an online compiler.
https://www.onlinegdb.com/online_c++_compiler

int calc(char*, char*);
int calc(char* const a, char* const b) {
    cout << a << b << endl;
}
int main() {
    char s1[] = "Hello", s2[] = "World";
    calc(s1, s2);
    return 0;
}