path: root/test/SemaCXX/constant-expression-cxx11.cpp

// RUN: %clang_cc1 -triple i686-linux -fsyntax-only -verify -std=c++11 -pedantic %s -Wno-comment

namespace StaticAssertFoldTest {

int x;
static_assert(++x, "test"); // expected-error {{not an integral constant expression}}
static_assert(false, "test"); // expected-error {{test}}

}

// FIXME: support const T& parameters here.
//template<typename T> constexpr T id(const T &t) { return t; }
template<typename T> constexpr T id(T t) { return t; }
// FIXME: support templates here.
//template<typename T> constexpr T min(const T &a, const T &b) {
//  return a < b ? a : b;
//}
//template<typename T> constexpr T max(const T &a, const T &b) {
//  return a < b ? b : a;
//}
constexpr int min(const int &a, const int &b) { return a < b ? a : b; }
constexpr int max(const int &a, const int &b) { return a < b ? b : a; }

struct MemberZero {
  constexpr int zero() { return 0; }
};

namespace DerivedToVBaseCast {

  struct U { int n; };
  struct V : U { int n; };
  struct A : virtual V { int n; };
  struct Aa { int n; };
  struct B : virtual A, Aa {};
  struct C : virtual A, Aa {};
  struct D : B, C {};

  D d;
  constexpr B *p = &d;
  constexpr C *q = &d;
  static_assert((void*)p != (void*)q, "");
  static_assert((A*)p == (A*)q, "");
  static_assert((Aa*)p != (Aa*)q, "");

  constexpr B &pp = d;
  constexpr C &qq = d;
  static_assert((void*)&pp != (void*)&qq, "");
  static_assert(&(A&)pp == &(A&)qq, "");
  static_assert(&(Aa&)pp != &(Aa&)qq, "");

  constexpr V *v = p;
  constexpr V *w = q;
  constexpr V *x = (A*)p;
  static_assert(v == w, "");
  static_assert(v == x, "");

  static_assert((U*)&d == p, "");
  static_assert((U*)&d == q, "");
  static_assert((U*)&d == v, "");
  static_assert((U*)&d == w, "");
  static_assert((U*)&d == x, "");

  struct X {};
  struct Y1 : virtual X {};
  struct Y2 : X {};
  struct Z : Y1, Y2 {};
  Z z;
  static_assert((X*)(Y1*)&z != (X*)(Y2*)&z, "");

}

namespace ConstCast {

constexpr int n1 = 0;
constexpr int n2 = const_cast<int&>(n1);
constexpr int *n3 = const_cast<int*>(&n1);
constexpr int n4 = *const_cast<int*>(&n1);
constexpr const int * const *n5 = const_cast<const int* const*>(&n3);
constexpr int **n6 = const_cast<int**>(&n3);
constexpr int n7 = **n5;
constexpr int n8 = **n6;

}

namespace TemplateArgumentConversion {
  template<int n> struct IntParam {};

  using IntParam0 = IntParam<0>;
  // FIXME: This should be accepted once we implement the new ICE rules.
  using IntParam0 = IntParam<id(0)>; // expected-error {{not an integral constant expression}}
  using IntParam0 = IntParam<MemberZero().zero>; // expected-error {{did you mean to call it with no arguments?}} expected-error {{not an integral constant expression}}
}

namespace CaseStatements {
  void f(int n) {
    switch (n) {
    // FIXME: Produce the 'add ()' fixit for this.
    case MemberZero().zero: // desired-error {{did you mean to call it with no arguments?}} expected-error {{not an integer constant expression}}
    // FIXME: This should be accepted once we implement the new ICE rules.
    case id(1): // expected-error {{not an integer constant expression}}
      return;
    }
  }
}

extern int &Recurse1;
int &Recurse2 = Recurse1, &Recurse1 = Recurse2;
constexpr int &Recurse3 = Recurse2; // expected-error {{must be initialized by a constant expression}}