In C++98/03, when binding a reference to an rvalue of

reference-compatible type, the implementation is permitted to make a
copy of the rvalue (or many such copies, even). However, even though
we don't make that copy, we are required to check for the presence of
a suitable copy constructor. With this change, we do.

Note that in C++0x we are not allowed to make these copies, so we test
both dialects separately.

Also note the FIXME in one of the C++03 tests, where we are not
instantiating default function arguments for the copy constructor we
pick (but do not call). The fix is obvious; eliminating the infinite
recursion it causes is not. Will address that next.

llvm-svn: 101704

1 files changed, 51 insertions, 0 deletions

diff --git a/clang/test/CXX/dcl.decl/dcl.init/dcl.init.ref/p5-cxx03-extra-copy.cpp b/clang/test/CXX/dcl.decl/dcl.init/dcl.init.ref/p5-cxx03-extra-copy.cpp
new file mode 100644
index 00000000000..5dd68613573
--- /dev/null
+++ b/clang/test/CXX/dcl.decl/dcl.init/dcl.init.ref/p5-cxx03-extra-copy.cpp
@@ -0,0 +1,51 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+// C++03 requires that we check for a copy constructor when binding a
+// reference to a temporary, since we are allowed to make a copy, Even
+// though we don't actually make that copy, make sure that we diagnose
+// cases where that copy constructor is somehow unavailable.
+
+struct X1 {
+  X1();
+  explicit X1(const X1&);
+};
+
+struct X2 {
+  X2();
+
+private:
+  X2(const X2&); // expected-note{{declared private here}}
+};
+
+struct X3 {
+  X3();
+
+private:
+  X3(X3&); // expected-note{{candidate constructor not viable: no known conversion from 'X3' to 'X3 &' for 1st argument}}
+};
+
+template<typename T>
+T get_value_badly() {
+  double *dp = 0;
+  T *tp = dp; // FIXME: Should get an error here, from instantiating the
+              // default argument of X4<int>
+  return T();
+}
+
+template<typename T>
+struct X4 {
+  X4();
+  X4(const X4&, T = get_value_badly<T>());
+};
+
+void g1(const X1&);
+void g2(const X2&);
+void g3(const X3&);
+void g4(const X4<int>&);
+
+void test() {
+  g1(X1()); // expected-error{{no viable constructor copying parameter of type 'X1'}}
+  g2(X2()); // expected-error{{calling a private constructor of class 'X2'}}
+  g3(X3()); // expected-error{{no viable constructor copying parameter of type 'X3'}}
+  g4(X4<int>());
+}