The problem was that the extended reference temporary never got its
array type completed. Doing it in the extension code didn't work
because by that time the initializer already has incomplete array type.
So let's handle it in grok_reference_init.
Tested x86_64-pc-linux-gnu, applying to trunk.
commit aa8d3da2f18be432567a538b1d22a4d7cf865aa5
Author: Jason Merrill <ja...@redhat.com>
Date: Wed Dec 3 17:32:05 2014 -0500
PR c++/64029
* decl.c (grok_reference_init): Complete array type.
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 2996ee6..5639b3d 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -4936,11 +4936,26 @@ grok_reference_init (tree decl, tree type, tree init, int flags)
init = build_x_compound_expr_from_list (init, ELK_INIT,
tf_warning_or_error);
- if (TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE
+ tree ttype = TREE_TYPE (type);
+ if (TREE_CODE (ttype) != ARRAY_TYPE
&& TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE)
/* Note: default conversion is only called in very special cases. */
init = decay_conversion (init, tf_warning_or_error);
+ /* check_initializer handles this for non-reference variables, but for
+ references we need to do it here or the initializer will get the
+ incomplete array type and confuse later calls to
+ cp_complete_array_type. */
+ if (TREE_CODE (ttype) == ARRAY_TYPE
+ && TYPE_DOMAIN (ttype) == NULL_TREE
+ && (BRACE_ENCLOSED_INITIALIZER_P (init)
+ || TREE_CODE (init) == STRING_CST))
+ {
+ cp_complete_array_type (&ttype, init, false);
+ if (ttype != TREE_TYPE (type))
+ type = cp_build_reference_type (ttype, TYPE_REF_IS_RVALUE (type));
+ }
+
/* Convert INIT to the reference type TYPE. This may involve the
creation of a temporary, whose lifetime must be the same as that
of the reference. If so, a DECL_EXPR for the temporary will be
diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist89.C b/gcc/testsuite/g++.dg/cpp0x/initlist89.C
new file mode 100644
index 0000000..e221664
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/initlist89.C
@@ -0,0 +1,4 @@
+// PR c++/64029
+// { dg-do compile { target c++11 } }
+
+const int (&in)[]{1,2,3,4,5};
