Hi,
On 07/30/2012 10:10 PM, Jason Merrill wrote:
On 07/28/2012 11:28 AM, Paolo Carlini wrote:
as the testcase shows (merge of 53624 & 54104), in case of local types
(possibly synthesized for a lambda) we check for the default template
arguments of the synthesized template parameters according to the rules
for *types* (instead of those for functions) and we spuriously reject.
As far as I can see we should just return early in such cases, because
we already checked upstream, thus I figured out logic that apparently
works, but I'm not sure it's the most precise and concise we can have.
It seems to me that the problem here is that the template parameters
in question are for an enclosing scope, not the temploid under
consideration.
Indeed, this is the problem.
We shouldn't be doing the default argument ordering check (or the
parameter pack order check) at all for non-primary templates.
Good, thanks. I didn't realize that we can use is_primary. Thus for
example the below passes testing: is it Ok or we can implement the
general idea in a different way?
Thanks!
Paolo.
////////////////////////
Index: testsuite/g++.dg/cpp0x/temp_default5.C
===================================================================
--- testsuite/g++.dg/cpp0x/temp_default5.C (revision 0)
+++ testsuite/g++.dg/cpp0x/temp_default5.C (revision 0)
@@ -0,0 +1,13 @@
+// { dg-options "-std=c++11" }
+
+template <class Z = void, class T>
+void Foo(T)
+{
+ struct X {};
+}
+
+template <class T = int, typename U>
+void f(const U&)
+{
+ auto g = [] () {};
+}
Index: cp/pt.c
===================================================================
--- cp/pt.c (revision 189981)
+++ cp/pt.c (working copy)
@@ -4267,7 +4267,8 @@ check_default_tmpl_args (tree decl, tree parms, in
/* Core issue 226 (C++0x only): the following only applies to class
templates. */
- if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
+ if ((cxx_dialect == cxx98)
+ || (TREE_CODE (decl) != FUNCTION_DECL && is_primary))
{
/* [temp.param]
