From adc651f305521e0e8e46fe1fee904532140d7a5e Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Tue, 2 Aug 2011 17:08:57 -0400
Subject: [PATCH] re PR c++/49803 ([C++0x] erroneous variant-member
 initialization in a union containing an anonymous struct)

	PR c++/49803
	* init.c (sort_mem_initializers): Initialize uses_unions_p here.
	(build_field_list): Not here.

From-SVN: r177213
---
 gcc/cp/ChangeLog                    |  4 ++++
 gcc/cp/init.c                       |  4 +---
 gcc/testsuite/ChangeLog             |  5 +++++
 gcc/testsuite/g++.dg/cpp0x/union5.C | 23 +++++++++++++++++++++++
 4 files changed, 33 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/union5.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index bba80e88918..dc138a187b2 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2011-08-02  Jason Merrill  <jason@redhat.com>
 
+	PR c++/49803
+	* init.c (sort_mem_initializers): Initialize uses_unions_p here.
+	(build_field_list): Not here.
+
 	PR c++/49834
 	* parser.c (build_range_temp): Split out from...
 	(cp_convert_range_for): ...here.
diff --git a/gcc/cp/init.c b/gcc/cp/init.c
index 52b948441f2..31171cfa686 100644
--- a/gcc/cp/init.c
+++ b/gcc/cp/init.c
@@ -655,8 +655,6 @@ build_field_list (tree t, tree list, int *uses_unions_p)
 {
   tree fields;
 
-  *uses_unions_p = 0;
-
   /* Note whether or not T is a union.  */
   if (TREE_CODE (t) == UNION_TYPE)
     *uses_unions_p = 1;
@@ -710,7 +708,7 @@ sort_mem_initializers (tree t, tree mem_inits)
   tree next_subobject;
   VEC(tree,gc) *vbases;
   int i;
-  int uses_unions_p;
+  int uses_unions_p = 0;
 
   /* Build up a list of initializations.  The TREE_PURPOSE of entry
      will be the subobject (a FIELD_DECL or BINFO) to initialize.  The
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 82f2776ba46..6b471694d3c 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2011-08-02  Jason Merrill  <jason@redhat.com>
+
+	PR c++/49803
+	* g++.dg/cpp0x/union5.C: New.
+
 2011-08-02  Daniel Kraft  <d@domob.eu>
 
 	PR fortran/49885
diff --git a/gcc/testsuite/g++.dg/cpp0x/union5.C b/gcc/testsuite/g++.dg/cpp0x/union5.C
new file mode 100644
index 00000000000..423b3482323
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/union5.C
@@ -0,0 +1,23 @@
+// PR c++/49803
+// { dg-options -std=c++0x }
+
+struct X
+{
+  X() = delete;
+};
+
+union Y
+{
+  // N3291=11-0061 12.6.2/8 says no initialization of
+  // of other variant members (i.e. m_x) should
+  // be performed.
+  Y() : m_char1{ }
+  { }
+
+  struct
+  {
+    char m_char1;
+  };
+
+  X    m_x;
+};