re PR c++/48289 (-pedantic breaks std::move)

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

From-SVN: r171461

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 8bf29c7a4578e9fdb5a257c568f8177379f2548e..b9fb0cdffac5f1deefebcd32f8bb2273eff00f8e 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2011-03-25  Jason Merrill  <jason@redhat.com>
+
+       PR c++/48289
+       * pt.c (build_non_dependent_expr): Keep dereferences outside the
+       NON_DEPENDENT_EXPR.
+
 2011-03-25  Kai Tietz  <ktietz@redhat.com>
 
        * decl.c (decls_match): Replace target hook

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index c8c1010182022f733e554fc5c7c86ddad68c3408..9032dd92dcb993260e190d1b918586ec12795d46 100644 (file)
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -18846,24 +18846,17 @@ 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.
-
-     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);
+  /* Otherwise, build a NON_DEPENDENT_EXPR.  */
+  return build1 (NON_DEPENDENT_EXPR, 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 bbeeb5dbc76d1b6b3ffda1bfe98394696b932ded..57a7102d9f9c5a8c8966d109abb894b99f8f59d7 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2011-03-25  Jason Merrill  <jason@redhat.com>
+
+       * g++.dg/cpp0x/move1.C: New.
+
 2011-03-25  Ira Rosen  <ira.rosen@linaro.org>
 
        PR target/48287

diff --git a/gcc/testsuite/g++.dg/cpp0x/move1.C b/gcc/testsuite/g++.dg/cpp0x/move1.C
new file mode 100644 (file)
index 0000000..12e363a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/move1.C
@@ -0,0 +1,15 @@
+// { 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 ) );
+ }
+};