1 files changed, 226 insertions, 0 deletions
diff --git a/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p4.cpp b/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p4.cpp
new file mode 100644
index 000000000000..9218bcf45bb4
--- /dev/null
+++ b/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p4.cpp
@@ -0,0 +1,226 @@
+// RUN: %clang_cc1 -verify -std=c++11 -fcxx-exceptions %s
+
+namespace N {
+  typedef char C;
+}
+
+namespace M {
+  typedef double D;
+}
+
+struct NonLiteral { // expected-note 2{{no constexpr constructors}}
+  NonLiteral() {}
+  NonLiteral(int) {}
+};
+struct Literal {
+  constexpr Literal() {}
+  operator int() const { return 0; }
+};
+
+// Note, the wording applies constraints to the definition of constexpr
+// constructors, but we intentionally apply all that we can to the declaration
+// instead. See DR1360.
+
+// In the definition of a constexpr constructor, each of the parameter types
+// shall be a literal type.
+struct S {
+  constexpr S(int, N::C);
+  constexpr S(int, NonLiteral, N::C); // expected-error {{constexpr constructor's 2nd parameter type 'NonLiteral' is not a literal type}}
+  constexpr S(int, NonLiteral = 42); // expected-error {{constexpr constructor's 2nd parameter type 'NonLiteral' is not a literal type}}
+
+  // In addition, either its function-body shall be = delete or = default
+  constexpr S() = default;
+  constexpr S(Literal) = delete;
+};
+
+// or it shall satisfy the following constraints:
+
+// - the class shall not have any virtual base classes;
+struct T : virtual S { // expected-note {{here}}
+  constexpr T(); // expected-error {{constexpr constructor not allowed in struct with virtual base classes}}
+};
+namespace IndirectVBase {
+  struct A {};
+  struct B : virtual A {}; // expected-note {{here}}
+  class C : public B {
+  public:
+    constexpr C(); // expected-error {{constexpr constructor not allowed in class with virtual base classes}}
+  };
+}
+
+// - its function-body shall not be a function-try-block;
+struct U {
+  constexpr U()
+    try // expected-error {{function try block not allowed in constexpr constructor}}
+    : u() {
+  } catch (...) {
+    throw;
+  }
+  int u;
+};
+
+// - the compound-statememt of its function-body shall contain only
+struct V {
+  constexpr V() {
+    //  - null statements,
+    ;
+
+    //  - static_assert-declarations,
+    static_assert(true, "the impossible happened!");
+
+    //  - typedef declarations and alias-declarations that do not define classes
+    //    or enumerations,
+    typedef int I;
+    typedef struct S T;
+    using J = int;
+    using K = int[sizeof(I) + sizeof(J)];
+    // Note, the standard requires we reject this.
+    struct U;
+
+    //  - using-declarations,
+    using N::C;
+
+    //  - and using-directives;
+    using namespace N;
+  }
+
+  constexpr V(int(&)[1]) {
+    for (int n = 0; n < 10; ++n) // expected-error {{statement not allowed in constexpr constructor}}
+      /**/;
+  }
+  constexpr V(int(&)[2]) {
+    constexpr int a = 0; // expected-error {{variables cannot be declared in a constexpr constructor}}
+  }
+  constexpr V(int(&)[3]) {
+    constexpr int ForwardDecl(int); // expected-error {{statement not allowed in constexpr constructor}}
+  }
+  constexpr V(int(&)[4]) {
+    typedef struct { } S1; // expected-error {{types cannot be defined in a constexpr constructor}}
+  }
+  constexpr V(int(&)[5]) {
+    using S2 = struct { }; // expected-error {{types cannot be defined in a constexpr constructor}}
+  }
+  constexpr V(int(&)[6]) {
+    struct S3 { }; // expected-error {{types cannot be defined in a constexpr constructor}}
+  }
+  constexpr V(int(&)[7]) {
+    return; // expected-error {{statement not allowed in constexpr constructor}}
+  }
+};
+
+// - every non-static data member and base class sub-object shall be initialized
+struct W {
+  int n; // expected-note {{member not initialized by constructor}}
+  constexpr W() {} // expected-error {{constexpr constructor must initialize all members}}
+};
+struct AnonMembers {
+  int a; // expected-note {{member not initialized by constructor}}
+  union { // expected-note 2{{member not initialized by constructor}}
+    char b;
+    struct {
+      double c;
+      long d; // expected-note {{member not initialized by constructor}}
+    };
+    union {
+      char e;
+      void *f;
+    };
+  };
+  struct { // expected-note {{member not initialized by constructor}}
+    long long g;
+    struct {
+      int h; // expected-note {{member not initialized by constructor}}
+      double i; // expected-note {{member not initialized by constructor}}
+    };
+    union { // expected-note 2{{member not initialized by constructor}}
+      char *j;
+      AnonMembers *k;
+    };
+  };
+
+  constexpr AnonMembers(int(&)[1]) : a(), b(), g(), h(), i(), j() {} // ok
+  // missing d, i, j/k union
+  constexpr AnonMembers(int(&)[2]) : a(), c(), g(), h() {} // expected-error {{constexpr constructor must initialize all members}}
+  constexpr AnonMembers(int(&)[3]) : a(), e(), g(), h(), i(), k() {} // ok
+  // missing h, j/k union
+  constexpr AnonMembers(int(&)[4]) : a(), c(), d(), g(), i() {} // expected-error {{constexpr constructor must initialize all members}}
+  // missing b/c/d/e/f union
+  constexpr AnonMembers(int(&)[5]) : a(), g(), h(), i(), k() {} // expected-error {{constexpr constructor must initialize all members}}
+  // missing a, b/c/d/e/f union, g/h/i/j/k struct
+  constexpr AnonMembers(int(&)[6]) {} // expected-error {{constexpr constructor must initialize all members}}
+};
+
+template<typename T> using Int = int;
+template<typename T>
+struct TemplateInit {
+  T a;
+  int b; // desired-note {{not initialized}}
+  Int<T> c; // desired-note {{not initialized}}
+  struct {
+    T d;
+    int e; // desired-note {{not initialized}}
+    Int<T> f; // desired-note {{not initialized}}
+  };
+  struct {
+    Literal l;
+    Literal m;
+    Literal n[3];
+  };
+  union { // desired-note {{not initialized}}
+    T g;
+    T h;
+  };
+  // FIXME: This is ill-formed (no diagnostic required). We should diagnose it.
+  constexpr TemplateInit() {} // desired-error {{must initialize all members}}
+};
+template<typename T> struct TemplateInit2 {
+  Literal l;
+  constexpr TemplateInit2() {} // ok
+};
+
+template<typename T> struct weak_ptr {
+  constexpr weak_ptr() : p(0) {}
+  T *p;
+};
+template<typename T> struct enable_shared_from_this {
+  weak_ptr<T> weak_this;
+  constexpr enable_shared_from_this() {} // ok
+};
+constexpr int f(enable_shared_from_this<int>);
+
+// - every constructor involved in initializing non-static data members and base
+//   class sub-objects shall be a constexpr constructor.
+//
+// FIXME: Implement this as part of the 'must be able to produce a constant
+// expression' rules.
+
+// - every assignment-expression that is an initializer-caluse appearing
+//   directly or indirectly within a brace-or-equal-initializer for a non-static
+//   data member that is not named by a mem-initializer-id shall be a constant
+//   expression; and
+//
+// Note, we deliberately do not implement this bullet, so that we can allow the
+// following example. (See N3308).
+struct X {
+  int a = 0;
+  int b = 2 * a + 1; // ok, not a constant expression.
+
+  constexpr X() {}
+  constexpr X(int c) : a(c) {} // ok, b initialized by 2 * c + 1
+};
+
+//  - every implicit conversion used in converting a constructor argument to the
+//    corresponding parameter type and converting a full-expression to the
+//    corresponding member type shall be one of those allowed in a constant
+//    expression.
+//
+// We implement the proposed resolution of DR1364 and ignore this bullet.
+
+
+namespace StdExample {
+  struct Length {
+    explicit constexpr Length(int i = 0) : val(i) { }
+  private:
+      int val;
+  };
+}