Trying to reference an overloaded method with const in C++ using clang -

in clang there this file. i'm trying reference 1 of overloaded methods:

00909   std::string getasstring(const printingpolicy &policy) const; 

i tried:

std::__cxx11::basic_string<char> (&p2)(const clang::printingpolicy&) = &clang::qualtype::getasstring; 

and got:

repl:1:73: error: address of overloaded function 'getasstring' not match required type 'std::__cxx11::basic_string<char> (const clang::printingpolicy &)' std::__cxx11::basic_string<char> (&p2)(const clang::printingpolicy&) = &clang::qualtype::getasstring 

/home/a/julia/usr/bin/../include/clang/ast/type.h:905:15: note: candidate function has different qualifiers **(expected none found const)**   std::string getasstring(const printingpolicy &policy) const; 

i tried:

std::__cxx11::basic_string<char> (&p1)(clang::printingpolicy&) = &clang::qualtype::getasstring; 

and got:

candidate function has type mismatch @ 1st parameter **(expected 'clang::printingpolicy &' has 'const clang::printingpolicy &')** 

am doing wrong or compiler broken?