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// PR c++/66477
// { dg-do compile { target c++11 } }
struct a { constexpr bool g() const { return true; } };
constexpr bool g(a&) { return true;}
constexpr bool h(a) { return true;}
a a1;
a& ar = a1;
void f(a ap, a& arp)
{
a a2;
a& ar2 = a2;
// Most of these are OK because no data is actually loaded.
static_assert (a1.g(),"");
static_assert (g(a1),"");
static_assert (h(a1),"");
static_assert (a2.g(),"");
static_assert (g(a2),"");
static_assert (h(a2),"");
static_assert (ap.g(),"");
static_assert (g(ap),"");
static_assert (h(ap),"");
static_assert (ar.g(),"");
static_assert (g(ar),"");
static_assert (h(ar),"");
// But these are specifically prohibited in [expr.const]/4.12:
// * an id-expression that refers to a variable or data member of reference
// type unless the reference has a preceding initialization and either
// ** it is usable in constant expressions or
// ** its lifetime began within the evaluation of e;
static_assert (ar2.g(),""); // { dg-error "constant" }
static_assert (g(ar2),""); // { dg-error "constant" }
static_assert (h(ar2),""); // { dg-error "constant" }
static_assert (arp.g(),"");
static_assert (g(arp),"");
static_assert (h(arp),""); // { dg-error "constant" }
}
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