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# cstyleCast
**Message**: C-style pointer casting<br/>
**Category**: Modernization<br/>
**Severity**: Style<br/>
**Language**: C++, not applicable for C code
## Description
Many developers feel that it's best to replace C casts with C++ casts.
There are several advantages with C++ casts:
* they permit only certain conversions
* they express the intent
* they are easy to identify
This checker is about C casts that converts to/from a pointer or reference.
**Note:** More "noisy" warnings exists that warn about all C casts. For instance Clang has
`-Wold-style-cast` and there is also such checking in Misra C++.
Dangerous conversions are covered by other warnings so this ID `cstyleCast` is primarily about
writing warnings for casts that are currently safe.
# Motivation
The motivation of this checker is to modernize c++ code.
## How to fix
You can use C++ casts such as `static_cast` to fix these warnings.
The `dynamic_cast` should rarelly be used to fix these warnings because dangerousTypeCast is
reported when that can be a good idea.
Before:
```cpp
struct Base{};
struct Derived: public Base {};
void foo(Base* base) {
Base *p = (Base*)derived; // <- cstyleCast, cast from derived object to base object is safe now
}
```
After:
```cpp
struct Base{};
struct Derived: public Base {};
void foo(Base* base) {
Derived *p = static_cast<Derived*>(base);
}
```
The `static_cast` ensures that there will not be loss of constness in the future.
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