[Bug c++/47897] New: [C++0x] static const member variable is not constant expression

[Bug c++/47897] New: [C++0x] static const member variable is not constant expression

[flast at flast dot jp]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47897

           Summary: [C++0x] static const member variable is not constant
                    expression
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: flast@flast.jp


GCC4.6.0(with C++0x mode) reject static const member variable depending
template parameter type.

---- testcase.C ----
template < typename T, T N >
struct S
{
    static const T value = N;
    typedef S< T, value + 1 > next;
};
--------------------

It seems caused by r170488 (git: cfa61f8435164f3205d70c7e1c5038b2d881aa1d).

In other case, GCC accepts codes.
For example:
---- testcase.C (accepted) ----
template < int N >
struct S
{
    static const int value = N;
    typedef S< value + 1 > next;
};
-------------------------------

Another case:
---- testcase.C (accepted) ----
template < typename T, T N >
struct S
{
    static constexpr T value = N;
    typedef S< T, value + 1 > next;
};
-------------------------------

[Bug c++/47897] [4.6 Regression][C++0x] static const member variable is not constant expression

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47897

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011.02.26 00:13:26
                 CC|                            |jason at gcc dot gnu.org
   Target Milestone|---                         |4.6.0
            Summary|[C++0x] static const member |[4.6 Regression][C++0x]
                   |variable is not constant    |static const member
                   |expression                  |variable is not constant
                   |                            |expression
     Ever Confirmed|0                           |1

--- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-02-26 00:13:26 UTC ---
Urgh, I can confirm this. Jason, can you have a look?

[Bug c++/47897] [4.6 Regression][C++0x] static const member variable is not constant expression

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47897

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED

--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> 2011-02-26 18:24:28 UTC ---
Oops.

[Bug c++/47897] [4.6 Regression][C++0x] static const member variable is not constant expression

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47897

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> 2011-02-27 08:13:22 UTC ---
Author: jason
Date: Sun Feb 27 08:13:16 2011
New Revision: 170532

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=170532
Log:
    PR c++/47897
    * semantics.c (non_const_var_error): Split out from...
    (cxx_eval_constant_expression): ...here.
    (potential_constant_expression_1) [VAR_DECL]: Use it.
    Allow dependent variables.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/regress/template-const1.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/semantics.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/g++.dg/cpp0x/regress/debug-debug7.C
    trunk/gcc/testsuite/g++.dg/cpp0x/regress/template-function1.C
    trunk/gcc/testsuite/g++.dg/debug/debug7.C
    trunk/gcc/testsuite/g++.dg/template/function1.C

[Bug c++/47897] [4.6 Regression][C++0x] static const member variable is not constant expression

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47897

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
                 CC|                            |jakub at gcc dot gnu.org
         Resolution|                            |FIXED

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-02-27 16:01:40 UTC ---
Fixed.