Suppress destructor calls

[msys5]

Brief Description

The result class implemented in the pimpl idiom is exported as ValueType with the CS_VALUE_TYPE macro, as shown below.

class LIB_EXPORT CS_VALUE_TYPE result {
    class handle;
private:
    handle *_pimpl;

public:
    bool is_ok() const;
}

class LIB_EXPORT lib {
public:
    result initialize();
}

Then, when there is an initialize() function that returns this result class, the output C# code is as follows.

public global::Result Initialize()
{
    var ___ret = new global::Result.__Internal();
    __Internal.Initialize(__Instance, new IntPtr(&___ret));
    var _____ret = global::Result.__CreateInstance(___ret);
    global::Result.__Internal.dtor(new __IntPtr(&___ret));
    return _____ret;
}

Since the result class is implemented in the pimpl idiom, calling the destructor at global::Result.__Internal.dtor(new __IntPtr(&___ret)); will disable the __pimpl members on the c++ side.
This situation requires an option to suppress destructor calls.

[tritao]

Feel free to send a PR with an option for this.