AMDG On 2/15/2011 9:35 AM, Gennadiy Rozental wrote:

I came to expect shared_ptr to handle undefined type, but here I got a test case (simplified from my use case) where it's actually breaks under msvc and works under gcc:

#include "boost/shared_ptr.hpp"

class UndefinedType;

//// base class for template class FooBase{ public: virtual ~FooBase();

virtual void fff(); };

template<typename T> class Foo: public FooBase { public: virtual void fff() { // any virtual implementations seen are [have to be able to be] instantiated. This fails unless T is visible. x.reset(x.get()); }

private: boost::shared_ptr<T> x; };

//// now use Foo as a field in a class class User { Foo<UndefinedType> y; };

It fails with:

...\boost-1.39\boost/checked_delete.hpp(32) : error C2027: use of undefined type 'UndefinedType'

Is this expected to compile? Is this MSVC issue?

Creating a shared_ptr from a raw pointer requires a complete type, unless you pass a deleter. MSVC must be instantiating Foo::fff sooner than gcc is. In Christ, Steven Watanabe