// N4606 Committee Draft, Standard for Programming Language C++
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/n4606.pdf 
#define msg "p205.cpp(94)8.3.2 References [dcl.ref]"

#include <iostream>

typedef int& A;
//const A aref = 3; // ill-formed; lvalue reference to non-const initialized with rvalue
//$ clang++ p205.cpp
//p205.cpp:8:1: warning: 'const' qualifier on reference type 'A' (aka 'int &') has no effect [-Wignored-qualifiers]
//const A aref = 3; // ill-formed; lvalue reference to non-const initialized with rvalue
^~~~~~
//p205.cpp:8:9: error: non-const lvalue reference to type 'int' cannot bind to a temporary of type 'int'
//const A aref = 3; // ill-formed; lvalue reference to non-const initialized with rvalue
//        ^      ~
//$ g++-7 p205.cpp
//p205.cpp:8:16: error: cannot bind non-const lvalue reference of type 'A {aka int&}' to an rvalue of type 'int'
// const A aref = 3; // ill-formed; lvalue reference to non-const initialized with rvalue
//                ^


void f(double& a) { a += 3.14; }
// ...

void m(){
  double d = 0;
  f(d);
}
//declares a to be a reference parameter of f so the call f(d) will add 3.14 to d.
int v[20];
// ...
int& g(int i) { return v[i]; }
// ...

void n(){
  m();
  g(3) = 7;
}
struct link {
  link* next;
};
link* first;
void h(link*& p) { // p is a reference to pointer
  p->next = first;
  first = p;
  p = 0;
}
void k() {
  link* q = new link;
  h(q);
}


int main(){
int i;
typedef int& LRI;
typedef int&& RRI;
LRI& r1 = i; // r1 has the type int&
const LRI& r2 = i; // r2 has the type int&
const LRI&& r3 = i; // r3 has the type int&
RRI& r4 = i; // r4 has the type int&
RRI&& r5 = 5; // r5 has the type int&&
decltype(r2)& r6 = i; // r6 has the type int&
decltype(r2)&& r7 = i; // r7 has the type int&

 k();
  n();
  std::cout<< "i="<<i << std::endl;
  std::cout<< "r1="<<r1 << std::endl;
  std::cout<< "r2="<<r2 << std::endl;
  std::cout<< "r3"<<r3 << std::endl;
  std::cout<< "r4="<<r4 << std::endl;
  std::cout<< "r5="<<r5 << std::endl;
  std::cout<< "r6="<<r6 << std::endl;
  std::cout<< "r7"<<r7 << std::endl;

  std::cout<< msg << std::endl;
  return EXIT_SUCCESS;
}

$ ./cppgl17.sh p205
$ clang++ p205.cpp
p205.cpp:46:1: warning: 'const' qualifier on reference type 'LRI' (aka 'int &') has no effect [-Wignored-qualifiers]
const LRI& r2 = i; // r2 has the type int&
^~~~~~
p205.cpp:47:1: warning: 'const' qualifier on reference type 'LRI' (aka 'int &') has no effect [-Wignored-qualifiers]
const LRI&& r3 = i; // r3 has the type int&
^~~~~~
2 warnings generated.
i=1
r1=1
r2=1
r31
r4=1
r5=5
r6=1
r71
p205.cpp(94)8.3.2 References [dcl.ref]

$ g++-7 p205.cpp
i=125268552
r1=125268552
r2=125268552
r3125268552
r4=125268552
r5=5
r6=125268552
r7125268552
p205.cpp(94)8.3.2 References [dcl.ref]