Can I assign a function pointer to a function with const parameters in C++?

Question

If i have a funtion int foo(const int A), am I allowed to do the following coding?

int (*Mypointer)(const int);
Mypointer = &foo;

In addition, am i also allowed to do the following which is without const in the declaration of the function pointer ?

int (*Mypointer)(int);
Mypointer = &foo;

Another interesting case is that, if I have int foo(int A) and I declare that

int(*Mypointer)(const int);
Mypointer = &foo;

I was given segmentation fault

I understand doubts about (2), but why would (1) be illegal? — HolyBlackCat
– HolyBlackCat, Commented Nov 4, 2021 at 18:38
Yes. Just tried it. I found that (1) and (2) both works. Another interesting case is that, if I have int foo(int A) and I declare that ``` int(*Mypointer)(const int); Mypointer = &foo; ``` I was given segmentation fault. I edited this case in the question — junyaozheng98
– junyaozheng98, Commented Nov 4, 2021 at 23:40
IMPORTANT NOTE: Violating "const" should give you a COMPILE error. Not necessarily a runtime "segmentation violation". Apples and oranges! — paulsm4
– paulsm4, Commented Nov 4, 2021 at 23:45

Tomek · Accepted Answer · 2021-11-04 18:56:33Z

1

They should both work.

const applied to a parameter passed by value has an effect ONLY in function body, making it immutable there.

answered Nov 4, 2021 at 18:56

Tomek

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