// PR c++/91264 // { dg-do compile { target c++14 } } struct F { const int f; constexpr F() : f(9) { } }; struct C { int n; const F f; constexpr C() : n(1) { n = 66; } }; struct A { int r; const C c; // { dg-message "originally declared" } constexpr A() : r(11) { r = 14; const_cast(c).n = 42; } // { dg-error "modifying a const object" } }; struct D { const A a; constexpr D() { } // { dg-message "in .constexpr. expansion of" } }; struct E { const D d; constexpr E() { } // { dg-message "in .constexpr. expansion of" } }; struct B { const E e; constexpr B(bool) { } // { dg-message "in .constexpr. expansion of" } }; constexpr B b(false); // { dg-message "in .constexpr. expansion of" } static_assert(b.e.d.a.c.n == 2, ""); // { dg-error "non-constant condition" }