1 files changed, 139 insertions, 0 deletions
diff --git a/clang/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p3.cpp b/clang/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p3.cpp
new file mode 100644
index 0000000..cafdd63
--- /dev/null
+++ b/clang/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p3.cpp
@@ -0,0 +1,139 @@
+// RUN: %clang_cc1 -verify -std=c++11 %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; }
+};
+
+struct S {
+  virtual int ImplicitlyVirtual() const = 0; // expected-note {{overridden virtual function}}
+};
+struct SS : S { 
+  int ImplicitlyVirtual() const;
+};
+
+// The definition of a constexpr function shall satisfy the following
+// constraints:
+struct T : SS, NonLiteral { // expected-note {{base class 'NonLiteral' of non-literal type}}
+  constexpr T();
+  constexpr int f(); // expected-error {{non-literal type 'T' cannot have constexpr members}}
+
+  //  - it shall not be virtual;
+  virtual constexpr int ExplicitlyVirtual() { return 0; } // expected-error {{virtual function cannot be constexpr}}
+
+  constexpr int ImplicitlyVirtual() { return 0; } // expected-error {{virtual function cannot be constexpr}}
+
+  //  - its return type shall be a literal type;
+  constexpr NonLiteral NonLiteralReturn() { return {}; } // expected-error {{constexpr function's return type 'NonLiteral' is not a literal type}}
+  constexpr void VoidReturn() { return; } // expected-error {{constexpr function's return type 'void' is not a literal type}}
+  constexpr ~T(); // expected-error {{destructor cannot be marked constexpr}}
+  typedef NonLiteral F();
+  constexpr F NonLiteralReturn2; // ok until definition
+
+  //  - each of its parameter types shall be a literal type;
+  constexpr int NonLiteralParam(NonLiteral) { return 0; } // expected-error {{constexpr function's 1st parameter type 'NonLiteral' is not a literal type}}
+  typedef int G(NonLiteral);
+  constexpr G NonLiteralParam2; // ok until definition
+
+  //  - its function-body shall be = delete, = default,
+  constexpr int Deleted() = delete;
+  // It's not possible for the function-body to legally be "= default" here.
+  // Other than constructors, only the copy- and move-assignment operators and
+  // destructor can be defaulted. Destructors can't be constexpr since they
+  // don't have a literal return type. Defaulted assignment operators can't be
+  // constexpr since they can't be const.
+  constexpr T &operator=(const T&) = default; // expected-error {{an explicitly-defaulted copy assignment operator may not have 'const', 'constexpr' or 'volatile' qualifiers}}
+};
+struct U {
+  constexpr U SelfReturn();
+  constexpr int SelfParam(U);
+};
+
+struct V : virtual U { // expected-note {{here}}
+  constexpr int F() { return 0; } // expected-error {{constexpr member function not allowed in struct with virtual base class}}
+};
+
+//  or a compound-statememt that contains only
+constexpr int AllowedStmts() {
+  //  - 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;
+
+  //  - using-directives
+  using namespace N;
+
+  //  - and exactly one return statement
+  return sizeof(K) + sizeof(C) + sizeof(K);
+}
+constexpr int ForStmt() {
+  for (int n = 0; n < 10; ++n) // expected-error {{statement not allowed in constexpr function}}
+    return 0;
+}
+constexpr int VarDecl() {
+  constexpr int a = 0; // expected-error {{variables cannot be declared in a constexpr function}}
+  return 0;
+}
+constexpr int FuncDecl() {
+  constexpr int ForwardDecl(int); // expected-error {{statement not allowed in constexpr function}}
+  return ForwardDecl(42);
+}
+constexpr int ClassDecl1() {
+  typedef struct { } S1; // expected-error {{types cannot be defined in a constexpr function}}
+  return 0;
+}
+constexpr int ClassDecl2() {
+  using S2 = struct { }; // expected-error {{types cannot be defined in a constexpr function}}
+  return 0;
+}
+constexpr int ClassDecl3() {
+  struct S3 { }; // expected-error {{types cannot be defined in a constexpr function}}
+  return 0;
+}
+constexpr int NoReturn() {} // expected-error {{no return statement in constexpr function}}
+constexpr int MultiReturn() {
+  return 0; // expected-note {{return statement}}
+  return 0; // expected-error {{multiple return statements in constexpr function}}
+}
+
+//  - every constructor call and implicit conversion used in initializing the
+//    return value shall be one of those allowed in a constant expression.
+//
+// We implement the proposed resolution of DR1364 and ignore this bullet.
+// However, we implement the spirit of the check as part of the p5 checking that
+// a constexpr function must be able to produce a constant expression.
+namespace DR1364 {
+  constexpr int f(int k) {
+    return k; // ok, even though lvalue-to-rvalue conversion of a function
+              // parameter is not allowed in a constant expression.
+  }
+  int kGlobal; // expected-note {{here}}
+  constexpr int f() { // expected-error {{constexpr function never produces a constant expression}}
+    return kGlobal; // expected-note {{read of non-const}}
+  }
+}