* call.c (convert_arg_to_ellipsis): Use the result of force_rvalue.

From-SVN: r253465

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index b5ae7451513348af1545822d1be596adb192eae4..c5c28f4fe92fcd98b5bd3873414cb0f5d21fdacb 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,7 @@
+2017-10-05  Jason Merrill  <jason@redhat.com>
+
+       * call.c (convert_arg_to_ellipsis): Use the result of force_rvalue.
+
 2017-10-05  Nathan Sidwell  <nathan@acm.org>
 
        Warn on MVP declarations

diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index bfd928823937106d03a17922d4d8e9e6f189e044..9d747be9d79b8a37cdc1a35d403063ffa9099169 100644 (file)
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -7165,29 +7165,24 @@ convert_arg_to_ellipsis (tree arg, tsubst_flags_t complain)
       /* In a template (or ill-formed code), we can have an incomplete type
         even after require_complete_type_sfinae, in which case we don't know
         whether it has trivial copy or not.  */
-      && COMPLETE_TYPE_P (arg_type))
+      && COMPLETE_TYPE_P (arg_type)
+      && !cp_unevaluated_operand)
     {
-      /* Build up a real lvalue-to-rvalue conversion in case the
-        copy constructor is trivial but not callable.  */
-      if (!cp_unevaluated_operand && CLASS_TYPE_P (arg_type))
-       force_rvalue (arg, complain);
-
       /* [expr.call] 5.2.2/7:
         Passing a potentially-evaluated argument of class type (Clause 9)
         with a non-trivial copy constructor or a non-trivial destructor
         with no corresponding parameter is conditionally-supported, with
         implementation-defined semantics.
 
-        We support it as pass-by-invisible-reference to the caller's
-        object.  That's different to named by-value parameters, which
-        construct a copy and pass a reference to that.
+        We support it as pass-by-invisible-reference, just like a normal
+        value parameter.
 
         If the call appears in the context of a sizeof expression,
         it is not potentially-evaluated.  */
-      if (cp_unevaluated_operand == 0
-         && (type_has_nontrivial_copy_init (arg_type)
-             || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)))
+      if (type_has_nontrivial_copy_init (arg_type)
+         || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type))
        {
+         arg = force_rvalue (arg, complain);
          if (complain & tf_warning)
            warning (OPT_Wconditionally_supported,
                     "passing objects of non-trivially-copyable "
@@ -7195,6 +7190,11 @@ convert_arg_to_ellipsis (tree arg, tsubst_flags_t complain)
                     arg_type);
          return cp_build_addr_expr (arg, complain);
        }
+      /* Build up a real lvalue-to-rvalue conversion in case the
+        copy constructor is trivial but not callable.  */
+      else if (CLASS_TYPE_P (arg_type))
+       force_rvalue (arg, complain);
+
     }
 
   return arg;

diff --git a/gcc/testsuite/g++.dg/ext/varargs2.C b/gcc/testsuite/g++.dg/ext/varargs2.C
new file mode 100644 (file)
index 0000000..13ddf5b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/varargs2.C
@@ -0,0 +1,17 @@
+// { dg-do run }
+
+int c;
+struct X { X() {}; X(const X&) { ++c; } };
+void Foo (X, ...) {}
+void bin (X &p)
+{
+  Foo (p, p);
+}
+
+int main()
+{
+  X x;
+  bin(x);
+  if (c != 2)
+    __builtin_abort();
+}