Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All
Expand Minimize
Important This document may not represent best practices for current development, links to downloads and other resources may no longer be valid. Current recommended version can be found here.

Compiler Warning (level 1) C4965

implicit box of integer 0; use nullptr or explicit cast

Visual C++ 2005 features implicit boxing of value types. An instruction that resulted in a null assignment using Managed Extensions for C++ now becomes an assignment to a boxed int.

For more information, see Implicit Boxing.

The following sample generates C4965.

// C4965.cpp
// compile with: /clr /W1
int main() {
   System::Object ^o = 0;   // C4965

   // the previous line is the same as the following line
   // using Managed Extensions for C++
   // System::Object *o = __box(0);

   // OK
   System::Object ^o2 = nullptr;
   System::Object ^o3 = safe_cast<System::Object^>(0);
}

Community Additions

ADD
Show:
© 2015 Microsoft