Compiler Warning (level 1) C4395
Visual Studio 2015
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The latest version of this topic can be found at Compiler Warning (level 1) C4395.
function' : member function will be invoked on a copy of the initonly data member 'member'
A member function was called on an initonly (C++/CLI) data member. C4395 warns that the initonly data member cannot be modified by the function.
The following sample generates C4395:
// C4395.cpp
// compile with: /W1 /clr
public value class V {
public:
V(int data) : m_data(data) {}
void Mutate() {
System::Console::WriteLine("Enter Mutate: m_data = {0}", m_data);
m_data *= 2;
System::Console::WriteLine("Leave Mutate: m_data = {0}", m_data);
}
int m_data;
};
public ref class R {
public:
static void f() {
System::Console::WriteLine("v.m_data = {0}", v.m_data);
v.Mutate(); // C4395
System::Console::WriteLine("v.m_data = {0}", v.m_data);
}
private:
initonly static V v = V(4);
};
int main() {
R::f();
}
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