---
title: Warning C26461
ms.date: 03/22/2018
f1_keywords: ["C26461", "USE_CONST_POINTER_ARGUMENTS"]
helpviewer_keywords: ["C26461"]
description: CppCoreCheck rule that enforces C++ Core Guidelines con.3
---
# Warning C26461

> The pointer argument '*argument*' for function '*function*' can be marked as a pointer to `const` (con.3).

## Remarks

A function with a `T*` argument has the potential to modify the value of the object. If that isn't the intent of the function, it's better to make the pointer a `const T*` instead.

Code analysis name: `USE_CONST_POINTER_ARGUMENTS`

## Example

```cpp
struct MyStruct
{
    void MemberFn1() const;
    void MemberFn2();
};

void Function1_Helper(const MyStruct* myStruct);
void Function1(MyStruct* myStruct) // C26461, neither of the operations on myStruct would modify the pointer's value.
{
    if (!myStruct)
        return;

    myStruct->MemberFn1();      // The member function is const
    Function1_Helper(myStruct); // Function1_Helper takes a const
}

void Function2(MyStruct* myStruct)
{
    if (!myStruct)
        return;

    myStruct->MemberFn2(); // The member function is non-const, so no C26461 will be issued
}
```

## See also

[C++ Core Guidelines con.3](https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#Rconst-ref).