Compiler Warning C4959

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cannot define unmanaged struct 'type' in /clr:safe because accessing its members yields unverifiable code

Accessing a member of an unmanaged type will produce an unverifiable (peverify.exe) image.

For more information, see Pure and Verifiable Code (C++/CLI).

This warning is issued as an error and can be disabled with the warning pragma or the /wd compiler option.

The following sample generates C4959:

// C4959.cpp
// compile with: /clr:safe

// Uncomment the following line to resolve.
// #pragma warning( disable : 4959 )
struct X {
   int data;
};

int main() {
   X x;
   x.data = 10;   // C4959
}