From: Jason Merrill <jason@redhat.com>
Date: Mon, 20 Feb 2017 06:05:38 +0000 (-0500)
Subject: PR c++/79470 - partial ordering with reference parameters
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=4cd159317cb88496122bd3999a04c56c513bd915;p=gcc.git

PR c++/79470 - partial ordering with reference parameters

	* pt.c (unify) [INDIRECT_REF]: Handle pack expansions.

From-SVN: r245589
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index ee222b43e0d..033831d7fd0 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2017-02-19  Jason Merrill  <jason@redhat.com>
 
+	PR c++/79470 - partial ordering with reference parameters
+	* pt.c (unify) [INDIRECT_REF]: Handle pack expansions.
+
 	PR c++/79500 - ICE with non-template deduction guide
 	* pt.c (do_class_deduction): Use STRIP_TEMPLATE rather than
 	DECL_TEMPLATE_RESULT.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 46e64986491..0a9f5d518d3 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -20918,8 +20918,13 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
     case INDIRECT_REF:
       if (REFERENCE_REF_P (parm))
 	{
+	  bool pexp = PACK_EXPANSION_P (arg);
+	  if (pexp)
+	    arg = PACK_EXPANSION_PATTERN (arg);
 	  if (REFERENCE_REF_P (arg))
 	    arg = TREE_OPERAND (arg, 0);
+	  if (pexp)
+	    arg = make_pack_expansion (arg);
 	  return unify (tparms, targs, TREE_OPERAND (parm, 0), arg,
 			strict, explain_p);
 	}
diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic-ref1.C b/gcc/testsuite/g++.dg/cpp0x/variadic-ref1.C
new file mode 100644
index 00000000000..441d386ad81
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/variadic-ref1.C
@@ -0,0 +1,10 @@
+// PR c++/79470
+// { dg-do compile { target c++11 } }
+
+    template < const int&... > struct AA;
+
+    template < > struct AA<> { };
+
+    template < const int& II, const int&... Is >
+    struct AA<II,Is...> { };
+