[Bug c++/51507] New: [C++0x] Function parameter pack doesn't use in template-argument-list

[Bug c++/51507] New: [C++0x] Function parameter pack doesn't use in template-argument-list

[digital-ghost_tsundere at hotmail dot co.jp]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51507

             Bug #: 51507
           Summary: [C++0x] Function parameter pack doesn't use in
                    template-argument-list
    Classification: Unclassified
           Product: gcc
           Version: 4.6.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: digital-ghost_tsundere@hotmail.co.jp


Following code cannot compile with gcc:

  template<typename ...>
  struct foo { typedef void type; };
  template<typename ...Ts>
  auto g(Ts ...ts)->
      typename foo<decltype(ts)...>::type
  {}
  int main() {
      g(42);
  }

Error:

  test1.cpp: In function 'int main()':
  test1.cpp:8:9: error: expansion pattern 'int' contains no argument packs
  test1.cpp:8:9: error: no matching function for call to 'g(int)'
  test1.cpp:8:9: note: candidate is:
  test1.cpp:4:6: note: template<class ... Ts> typename foo<decltype
(ts)...>::type g(Ts ...)

I think decltype(fs()) is a valid template-argument pattern for foo.

[Bug c++/51507] [C++0x] Function parameter pack doesn't use in template-argument-list

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51507

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2011-12-22
                 CC|                            |jason at gcc dot gnu.org
         AssignedTo|unassigned at gcc dot       |jason at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

[Bug c++/51507] [C++0x] Function parameter pack doesn't use in template-argument-list

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51507

--- Comment #1 from Jason Merrill <jason at gcc dot gnu.org> 2011-12-23 22:00:21 UTC ---
Author: jason
Date: Fri Dec 23 22:00:13 2011
New Revision: 182668

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=182668
Log:
    PR c++/51507
    * search.c (at_function_scope_p): Also check cfun.
    * pt.c (tsubst_pack_expansion): Check it instead of
    cp_unevaluated_operand.
    (instantiate_template_1): Clear current_function_decl.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/variadic121.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/pt.c
    trunk/gcc/cp/search.c
    trunk/gcc/testsuite/ChangeLog

[Bug c++/51507] [C++0x] Function parameter pack doesn't use in template-argument-list

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51507

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.0

--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> 2011-12-23 22:10:33 UTC ---
Fixed for 4.7.