From b788d659bb840088b06fd6c8e29830daefd121d7 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Mon, 28 Mar 2011 11:06:28 -0400
Subject: [PATCH] revert: re PR c++/48289 (-pedantic breaks std::move)

        Revert:
        PR c++/48289
        * pt.c (build_non_dependent_expr): Keep dereferences outside the
        NON_DEPENDENT_EXPR.

From-SVN: r171607
---
 gcc/cp/ChangeLog                   |  7 +++++++
 gcc/cp/pt.c                        | 23 +++++++++++++++--------
 gcc/testsuite/ChangeLog            |  5 +++++
 gcc/testsuite/g++.dg/cpp0x/move1.C | 15 ---------------
 4 files changed, 27 insertions(+), 23 deletions(-)
 delete mode 100644 gcc/testsuite/g++.dg/cpp0x/move1.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index a6b681f878e7..7a4d367ce555 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2011-03-28  Jason Merrill  <jason@redhat.com>
+
+	Revert:
+	PR c++/48289
+	* pt.c (build_non_dependent_expr): Keep dereferences outside the
+	NON_DEPENDENT_EXPR.
+
 2011-03-25  Jason Merrill  <jason@redhat.com>
 
 	PR c++/48289
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index bb93667b82df..f458f38a8c36 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -18273,17 +18273,24 @@ build_non_dependent_expr (tree expr)
 		   TREE_OPERAND (expr, 0),
 		   build_non_dependent_expr (TREE_OPERAND (expr, 1)));
 
-  /* Keep dereferences outside the NON_DEPENDENT_EXPR so lvalue_kind
-     doesn't need to look inside.  */
-  if (TREE_CODE (expr) == INDIRECT_REF && REFERENCE_REF_P (expr))
-    return convert_from_reference (build_non_dependent_expr
-				   (TREE_OPERAND (expr, 0)));
-
   /* If the type is unknown, it can't really be non-dependent */
   gcc_assert (TREE_TYPE (expr) != unknown_type_node);
 
-  /* Otherwise, build a NON_DEPENDENT_EXPR.  */
-  return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
+  /* Otherwise, build a NON_DEPENDENT_EXPR.
+
+     REFERENCE_TYPEs are not stripped for expressions in templates
+     because doing so would play havoc with mangling.  Consider, for
+     example:
+
+       template <typename T> void f<T& g>() { g(); }
+
+     In the body of "f", the expression for "g" will have
+     REFERENCE_TYPE, even though the standard says that it should
+     not.  The reason is that we must preserve the syntactic form of
+     the expression so that mangling (say) "f<g>" inside the body of
+     "f" works out correctly.  Therefore, the REFERENCE_TYPE is
+     stripped here.  */
+  return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
 }
 
 /* ARGS is a vector of expressions as arguments to a function call.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index c51ab21dc45e..88ab1cdc3cd1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2011-03-28  Jason Merrill  <jason@redhat.com>
+
+	Revert:
+	* g++.dg/cpp0x/move1.C: New.
+
 2011-03-28  Richard Sandiford  <richard.sandiford@linaro.org>
 
 	PR target/47553
diff --git a/gcc/testsuite/g++.dg/cpp0x/move1.C b/gcc/testsuite/g++.dg/cpp0x/move1.C
deleted file mode 100644
index 12e363a8cabe..000000000000
--- a/gcc/testsuite/g++.dg/cpp0x/move1.C
+++ /dev/null
@@ -1,15 +0,0 @@
-// { dg-options "-std=c++0x -pedantic-errors" }
-
-#include <utility>
-
-class A { };
-
-static void g ( A && ) { }
-
-template < class T > class B {
-public:
- void f ( ) {
-  A a;
-  g ( std :: move ( a ) );
- }
-};
-- 
2.47.2