Core issue 934

	Core issue 934
	* call.c (reference_binding): Implement binding to { }.
	(initialize_reference): Binding temporary to non-const && is fine.
	* decl.c (grok_reference_init): Remove error for CONSTRUCTOR.

From-SVN: r149873

6 files changed, 56 insertions, 11 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 520ae54..86f8b50 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2009-07-21  Jason Merrill  <jason@redhat.com>
+
+	Core issue 934
+	* call.c (reference_binding): Implement binding to { }.
+	(initialize_reference): Binding temporary to non-const && is fine.
+	* decl.c (grok_reference_init): Remove error for CONSTRUCTOR.
+
 2009-07-17  Richard Guenther  <rguenther@suse.de>
 
 	PR c/40401
diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index f4b5b02..845fa56 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -1221,7 +1221,21 @@ reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
       lvalue_p = clk_ordinary;
       from = TREE_TYPE (from);
     }
-  else if (expr)
+
+  if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
+    {
+      maybe_warn_cpp0x ("extended initializer lists");
+      conv = implicit_conversion (to, from, expr, c_cast_p,
+				  flags);
+      if (!CLASS_TYPE_P (to)
+	  && CONSTRUCTOR_NELTS (expr) == 1)
+	{
+	  expr = CONSTRUCTOR_ELT (expr, 0)->value;
+	  from = TREE_TYPE (expr);
+	}
+    }
+
+  if (lvalue_p == clk_none && expr)
     lvalue_p = real_lvalue_p (expr);
 
   tfrom = from;
@@ -1363,8 +1377,9 @@ reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
   if (!(flags & LOOKUP_COPY_PARM))
     flags |= LOOKUP_ONLYCONVERTING;
 
-  conv = implicit_conversion (to, from, expr, c_cast_p,
-			      flags);
+  if (!conv)
+    conv = implicit_conversion (to, from, expr, c_cast_p,
+				flags);
   if (!conv)
     return NULL;
 
@@ -7541,6 +7556,7 @@ initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
   if (!conv || conv->bad_p)
     {
       if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
+	  && !TYPE_REF_IS_RVALUE (type)
 	  && !real_lvalue_p (expr))
 	error ("invalid initialization of non-const reference of "
 	       "type %qT from a temporary of type %qT",
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 251d0a3..6fa9428 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -4370,13 +4370,6 @@ grok_reference_init (tree decl, tree type, tree init, tree *cleanup)
       return NULL_TREE;
     }
 
-  if (TREE_CODE (init) == CONSTRUCTOR)
-    {
-      error ("ISO C++ forbids use of initializer list to "
-	     "initialize reference %qD", decl);
-      return NULL_TREE;
-    }
-
   if (TREE_CODE (init) == TREE_LIST)
     init = build_x_compound_expr_from_list (init, "initializer");
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index ed0b13a..d007c46 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2009-07-21  Jason Merrill  <jason@redhat.com>
+
+	Core issue 934
+	* g++.dg/cpp0x/initlist22.C: New.
+
 2009-07-21  Uros Bizjak  <ubizjak@gmail.com>
 
 	* gcc.target/i386/vectorize8.c: New test.
diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist22.C b/gcc/testsuite/g++.dg/cpp0x/initlist22.C
new file mode 100644
index 0000000..bf1c554
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/initlist22.C
@@ -0,0 +1,24 @@
+// Core issue 934
+// { dg-options "-std=c++0x" }
+
+int i;
+
+int& r1{ i };			// OK, direct binding
+int&& r2{ i };			// OK, direct binding
+
+int& r3{ };			// { dg-error "" } reference to temporary
+int&& r4{ };			// OK, reference to temporary
+
+struct A { int i; } a;
+
+A& r5 { i };			// { dg-error "" } reference to temporary
+A&& r6 { i };			// OK, aggregate initialization of temporary
+A& r7 { a };			// { dg-error "" } invalid aggregate initializer for A
+A&& r8 { a };			// { dg-error "" } invalid aggregate initializer for A
+
+struct B { B(int); int i; } b(0);
+
+B& r9 { i };			// { dg-error "" } reference to temporary
+B&& r10 { i };			// OK, make temporary with B(int) constructor
+B& r11 { b };			// { dg-error "" } reference to temporary
+B&& r12 { b };			// OK, make temporary with copy constructor
diff --git a/gcc/testsuite/g++.old-deja/g++.brendan/init4.C b/gcc/testsuite/g++.old-deja/g++.brendan/init4.C
index 71e7cd6..aa2bfb6 100644
--- a/gcc/testsuite/g++.old-deja/g++.brendan/init4.C
+++ b/gcc/testsuite/g++.old-deja/g++.brendan/init4.C
@@ -2,4 +2,4 @@
 // GROUPS passed initialization
 struct CharList { int i; };
 
-const CharList& terminals = { 1 };// { dg-error "" } .*
+const CharList& terminals = { 1 }; // { dg-error "initializer lists" } c++0x