clang/test/SemaCXX/constexpr-default-arg.cpp

   1 // RUN: %clang_cc1 -std=c++1y -o - -emit-llvm -verify %s
   2 // RUN: %clang_cc1 -std=c++1y -fexperimental-new-constant-interpreter -o - -emit-llvm -verify %s
   3
   4 namespace default_arg_temporary {
   5
   6 constexpr bool equals(const float& arg = 1.0f) {
   7   return arg == 1.0f;
   8 }
   9
  10 constexpr const int &x(const int &p = 0) {
  11   return p;
  12 }
  13
  14 struct S {
  15   constexpr S(const int &a = 0) {}
  16 };
  17
  18 void test_default_arg2() {
  19   // This piece of code used to cause an assertion failure in
  20   // CallStackFrame::createTemporary because the same MTE is used to initilize
  21   // both elements of the array (see PR33140).
  22   constexpr S s[2] = {};
  23
  24   // This piece of code used to cause an assertion failure in
  25   // CallStackFrame::createTemporary because multiple CXXDefaultArgExpr share
  26   // the same MTE (see PR33140).
  27   static_assert(equals() && equals(), "");
  28
  29   // Test that constant expression evaluation produces distinct lvalues for
  30   // each call.
  31   static_assert(&x() != &x(), "");
  32 }
  33
  34 // Check that multiple CXXDefaultInitExprs don't cause an assertion failure.
  35 struct A { int &&r = 0; };
  36 struct B { A x, y; };
  37 B b = {}; // expected-no-diagnostics
  38
  39 }