--- description: "Learn more about: __ptr32, __ptr64" title: "__ptr32, __ptr64" ms.date: "10/09/2018" f1_keywords: ["__ptr32_cpp", "__ptr64_cpp", "__ptr32", "__ptr64", "_ptr32", "_ptr64"] helpviewer_keywords: ["__ptr64 keyword [C++]", "_ptr32 keyword [C++]", "ptr32 keyword [C++]", "ptr64 keyword [C++]", "_ptr64 keyword [C++]", "__ptr32 keyword [C++]"] ms.assetid: afb563d8-7458-4fe7-9c30-bd4b5385a59f --- # __ptr32, __ptr64 **Microsoft Specific** **`__ptr32`** represents a native pointer on a 32-bit system, while **`__ptr64`** represents a native pointer on a 64-bit system. The following example shows how to declare each of these pointer types: ```cpp int * __ptr32 p32; int * __ptr64 p64; ``` On a 32-bit system, a pointer declared with **`__ptr64`** is truncated to a 32-bit pointer. On a 64-bit system, a pointer declared with **`__ptr32`** is coerced to a 64-bit pointer. > [!NOTE] > You cannot use **`__ptr32`** or **`__ptr64`** when compiling with **/clr:pure**. Otherwise, Compiler Error C2472 will be generated. The **/clr:pure** and **/clr:safe** compiler options are deprecated in Visual Studio 2015 and unsupported in Visual Studio 2017. For compatibility with previous versions, **_ptr32** and **_ptr64** are synonyms for **`__ptr32`** and **`__ptr64`** unless compiler option [/Za \(Disable language extensions)](../build/reference/za-ze-disable-language-extensions.md) is specified. ## Example The following example shows how to declare and allocate pointers with the **`__ptr32`** and **`__ptr64`** keywords. ```cpp #include #include int main() { using namespace std; int * __ptr32 p32; int * __ptr64 p64; p32 = (int * __ptr32)malloc(4); *p32 = 32; cout << *p32 << endl; p64 = (int * __ptr64)malloc(4); *p64 = 64; cout << *p64 << endl; } ``` ```Output 32 64 ``` **END Microsoft Specific** ## See also [Built-in types](../cpp/fundamental-types-cpp.md)