2013/8/4 gast128 <gast128@hotmail.com>

Dear all,

I get a compilation error with Boost.Variant (which compiles fine on
previous releases) with vstudio 2010 when a function returns a const
Boost.Variant, e.g.:

typedef boost::variant<int, double> Variant;

const Variant GetVar()
{
return Variant();
}

void TestVariantDnc()
{
const Variant var = GetVar();
}

This gives error C2666 ('boost::variant<T0_,T1>::convert_construct' : 3
overloads have similar conversions').

I think this is an interesting example. For a copyable and movable type T:

const T f();

int main()

{

T t = f(); //???

Should this:

a) not compile? (like in the variant example above)

b) use the copy constructor instead of moving?

c) move anyway?

Looks like this is caused by move-emulation for variant, isn't it?

Regards,

Kris