[dcl.init.ref] p5.4.1 says

The result of the call to the conversion function, as described for the non-reference copy-initialization, is then used to direct-initialize the reference.

This rule in introduced by CWG1571. The intent is that check the cv-qualification between the referenced type of the reference that is being initialized and the return type of the function call. However, a function call is either a glvalue or prvalue, the result of which is either an entity(i.e. an object or a function) or a value, which is not what we expect for checking whether discarding the cv-qualification. Moreover, the initializer expression used to initialize a reference is first to be an expression.

Another issue is that "the call to the conversion function" sounds like the selected function can only be the conversion function; a constructor is not a conversion function.

So, in order to clarify such two issues, [dcl.init.ref] p5.4.1 might be changed to

The call to the selected function, as described for the non-reference copy-initialization, is then used to direct-initialize the reference.