compiler-error-c3637.md

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Learn more about: Compiler Error C3637	Compiler Error C3637	11/04/2016	C3637	C3637	72391377-8519-43d9-870a-73a6423deb74

Compiler Error C3637

'function' : a friend function definition cannot be a specialization of a function type

A friend function was defined incorrectly for a template or generic.

The following sample generates C3637:

// C3637.cpp
template <class T>
void f();

struct S {
   friend void f<int>() {}   // C3637
};

Possible resolution:

// C3637b.cpp
// compile with: /c
template <class T>
void f();

struct S {
   friend void f() {}
};

C3637 can also occur when using generics:

// C3637c.cpp
// compile with: /clr

generic <class T>
void gf();

struct S {
   friend void gf<int>() {}   // C3637
};

Possible resolution:

// C3637d.cpp
// compile with: /clr /c
generic <class T>
void gf();

struct S {
   friend void gf() {}
};