017-04-17 Bernd Edlinger <bernd.edlinger@hotmail.de>

        
        PR c++/80287
        * class.c (fixup_may_alias): Fix all type variants.

gcc/testsuite
2017-04-17  Bernd Edlinger  <bernd.edlinger@hotmail.de> 

        PR c++/80287
        * g++.dg/lto/pr80287_0.C: New test.


git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@246955 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 107 insertions, 3 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index c5db14c9dc1..3d36c6bd690 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2017-04-17  Bernd Edlinger  <bernd.edlinger@hotmail.de>
+
+	PR c++/80287
+	* class.c (fixup_may_alias): Fix all type variants.
+
 2017-04-17  Jason Merrill  <jason@redhat.com>
 
 	PR c++/80415 - wrong error with default arg and array reference.
diff --git a/gcc/cp/class.c b/gcc/cp/class.c
index 940cead072e..2b039fe628f 100644
--- a/gcc/cp/class.c
+++ b/gcc/cp/class.c
@@ -2060,12 +2060,14 @@ fixup_type_variants (tree t)
 static void
 fixup_may_alias (tree klass)
 {
-  tree t;
+  tree t, v;
 
   for (t = TYPE_POINTER_TO (klass); t; t = TYPE_NEXT_PTR_TO (t))
-    TYPE_REF_CAN_ALIAS_ALL (t) = true;
+    for (v = TYPE_MAIN_VARIANT (t); v; v = TYPE_NEXT_VARIANT (v))
+      TYPE_REF_CAN_ALIAS_ALL (v) = true;
   for (t = TYPE_REFERENCE_TO (klass); t; t = TYPE_NEXT_REF_TO (t))
-    TYPE_REF_CAN_ALIAS_ALL (t) = true;
+    for (v = TYPE_MAIN_VARIANT (t); v; v = TYPE_NEXT_VARIANT (v))
+      TYPE_REF_CAN_ALIAS_ALL (v) = true;
 }
 
 /* Early variant fixups: we apply attributes at the beginning of the class
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 204d8636d9d..6f9932a3b51 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2017-04-17  Bernd Edlinger  <bernd.edlinger@hotmail.de>
+
+	PR c++/80287
+	* g++.dg/lto/pr80287_0.C: New test.
+
 2017-04-12  Kelvin Nilsen  <kelvin@gcc.gnu.org>
 
 	PR target/80315
diff --git a/gcc/testsuite/g++.dg/lto/pr80287_0.C b/gcc/testsuite/g++.dg/lto/pr80287_0.C
new file mode 100644
index 00000000000..ea655c97b29
--- /dev/null
+++ b/gcc/testsuite/g++.dg/lto/pr80287_0.C
@@ -0,0 +1,92 @@
+// { dg-lto-options { "-std=gnu++17" } }
+// { dg-lto-do run }
+
+// Copyright (C) 2014-2017 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <any>
+#define VERIFY(x) if (!(x)) __builtin_abort()
+
+using std::any;
+using std::any_cast;
+
+bool moved = false;
+bool copied = false;
+
+struct X
+{
+  X() = default;
+  X(const X&) { copied = true; }
+  X(X&& x) { moved = true; }
+};
+
+struct X2
+{
+  X2() = default;
+  X2(const X2&) { copied = true; }
+  X2(X2&& x) noexcept { moved = true; }
+}__attribute((may_alias));
+
+void test01()
+{
+  moved = false;
+  X x;
+  any a1;
+  a1 = x;
+  VERIFY(moved == false);
+  any a2;
+  copied = false;
+  a2 = std::move(x);
+  VERIFY(moved == true);
+  VERIFY(copied == false);
+}
+
+void test02()
+{
+  moved = false;
+  X x;
+  any a1;
+  a1 = x;
+  VERIFY(moved == false);
+  any a2;
+  copied = false;
+  a2 = std::move(a1);
+  VERIFY(moved == false);
+  VERIFY(copied == false);
+}
+
+void test03()
+{
+  moved = false;
+  X2 x;
+  any a1;
+  a1 = x;
+  VERIFY(copied && moved);
+  any a2;
+  moved = false;
+  copied = false;
+  a2 = std::move(a1);
+  VERIFY(moved == true);
+  VERIFY(copied == false);
+}
+
+int main()
+{
+  test01();
+  test02();
+  test03();
+}