compiler-warning-level-1-c4812.md

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Learn more about: Compiler Warning (level 1) C4812	Compiler Warning (level 1) C4812	11/04/2016	C4812	C4812	a7f5721f-2019-44de-ad62-ed30bac8b1f3

Compiler Warning (level 1) C4812

obsolete declaration style: please use 'new_syntax' instead

In the current release of Visual C++, the explicit constructor specialization is still supported, but it may not be supported in a future release.

The following sample generates C4812:

// C4812.cpp
// compile with: /W1 /c
template <class T>
class MyClass;

template<class T>
class MyClass<T*> {
   MyClass();
};

template<class T>
MyClass<T*>::MyClass<T*>() {}   // C4812
// try the following line instead
// MyClass<T*>::MyClass() {}