no out-of-line virtual method definitions

[mrdebug]

Hi, this struct

struct InterfaceA {
    virtual void Clean() {}
    InterfaceA() {}
    virtual ~InterfaceA() {}
};

emits the warning

warning: 'InterfaceA' has no out-of-line virtual method definitions; its vtable will be emitted in every translation unit

Can someone explain how to resolve?

[jsulm]

@mrdebug See https://stackoverflow.com/questions/28786473/clang-no-out-of-line-virtual-method-definitions-pure-abstract-c-class?rq=1

// B::x() is inline in the class definition.

struct B {
    virtual void x() {
    }
    virtual ~B() {
    }
};

If you move the destructor body to the cpp file the warning should disappear.

[mrdebug]

Perfect and now

.h
struct DefaultStructInterface {
    DefaultStructInterface() {}
    virtual ~DefaultStructInterface();
    virtual void Clean() {}
};

but the line of code

.cpp
DefaultStructInterface::~DefaultStructInterface() {}

causes

warning: definition of implicit copy assignment operator for 'DefaultStructInterface' is deprecated because it has a user-declared destructor

[mrjj]

Hi
Are you using the clang compiler ?
anyway, this might be interesting
https://stackoverflow.com/questions/51863588/warning-definition-of-implicit-copy-constructor-is-deprecated

[VRonin]

@mrdebug said in no out-of-line virtual method definitions:

is deprecated because it has a user-declared destructor

This is just the good old rule-of-3 (now became rule-of-5). why don't you just =default them instead of having an empty body to avoid headakes?