commit 7788d30617c68e660a73288a0c8adbe7d2d0a714
Author: Jason Merrill <jason@redhat.com>
Date: Thu Feb 25 09:56:42 2016 -0500
PR c++/69842
* method.c (forward_parm): Handle parameter packs.
* lambda.c (maybe_add_lambda_conv_op): Use it for them.
@@ -29,6 +29,7 @@ along with GCC; see the file COPYING3. If not see
#include "cgraph.h"
#include "tree-iterator.h"
#include "toplev.h"
+#include "gimplify.h"
/* Constructor for a lambda expression. */
@@ -952,23 +953,18 @@ maybe_add_lambda_conv_op (tree type)
if (generic_lambda_p)
{
- if (DECL_PACK_P (tgt))
- {
- tree a = make_pack_expansion (tgt);
- if (decltype_call)
- CALL_EXPR_ARG (decltype_call, ix) = copy_node (a);
- PACK_EXPANSION_LOCAL_P (a) = true;
- CALL_EXPR_ARG (call, ix) = a;
- }
- else
- {
- ++processing_template_decl;
- tree a = forward_parm (tgt);
- --processing_template_decl;
- CALL_EXPR_ARG (call, ix) = a;
- if (decltype_call)
- CALL_EXPR_ARG (decltype_call, ix) = copy_node (a);
- }
+ ++processing_template_decl;
+ tree a = forward_parm (tgt);
+ --processing_template_decl;
+
+ CALL_EXPR_ARG (call, ix) = a;
+ if (decltype_call)
+ CALL_EXPR_ARG (decltype_call, ix) = unshare_expr (a);
+
+ if (PACK_EXPANSION_P (a))
+ /* Set this after unsharing so it's not in decltype_call. */
+ PACK_EXPANSION_LOCAL_P (a) = true;
+
++ix;
}
else
@@ -481,9 +481,12 @@ tree
forward_parm (tree parm)
{
tree exp = convert_from_reference (parm);
- if (TREE_CODE (TREE_TYPE (parm)) != REFERENCE_TYPE
- || TYPE_REF_IS_RVALUE (TREE_TYPE (parm)))
- exp = move (exp);
+ tree type = TREE_TYPE (parm);
+ if (DECL_PACK_P (parm))
+ type = PACK_EXPANSION_PATTERN (type);
+ exp = build_static_cast (type, exp, tf_warning_or_error);
+ if (DECL_PACK_P (parm))
+ exp = make_pack_expansion (exp);
return exp;
}
new file mode 100644
@@ -0,0 +1,20 @@
+// PR c++/69842
+// { dg-do compile { target c++14 } }
+
+template <class T, class U> struct assert_same;
+template <class T> struct assert_same<T,T> {};
+
+template<typename T>
+void sink(T &&)
+{
+ assert_same<int,T> a;
+}
+
+int main()
+{
+ auto const g([](auto &&... _var) {
+ sink(static_cast<decltype(_var)>(_var)...);
+ });
+
+ g(0);
+}