Compiler Warning C4972
Directly modifying or treating the result of an unbox operation as an lvalue is unverifiable
Dereferencing a handle to a value type, also known as unboxing, and then assigning to it is not verifiable.
For more information, see Boxing.
Example
The following sample generates C4972.
// C4972.cpp
// compile with: /clr:safe
using namespace System;
ref struct R {
int ^ p; // a value type
};
int main() {
R ^ r = gcnew R;
*(r->p) = 10; // C4972
// OK
r->p = 10;
Console::WriteLine( r->p );
Console::WriteLine( *(r->p) );
}
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