#![feature(const_trait_impl)]#[const_trait]traitConstDefaultFn:Sized{fnb(self);fna(self){self.b();}}structNonConstImpl;structConstImpl;implConstDefaultFnforNonConstImpl{fnb(self){}}implconstConstDefaultFnforConstImpl{fnb(self){}}constfntest(){NonConstImpl.a();//~^ ERROR the trait boundConstImpl.a();}fnmain(){}