[Bug c++/59554] New: Errors with const and volatile in templates.

[isak50 at mail dot ru]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59554

            Bug ID: 59554
           Summary: Errors with const and volatile in templates.
           Product: gcc
           Version: 4.8.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: isak50 at mail dot ru

Created attachment 31477
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=31477&action=edit
source.ii

// templates mis_... don't find out a const and a volatile. Also std tools of   
// <type_traits> fail.

// Windows, TDM GCC



#include <stdio.h>


template <typename _Ty>
    struct mis_const                    {  static void ch() { printf("is const:
   false\n"); }  };

template <typename _Ty>
    struct mis_const<const _Ty>         {  static void ch() { printf("is const:
   true\n"); }  };

template <typename _Ty>
    struct mis_volatile                 {  static void ch() { printf("is
volatile: false\n"); }  };

template <typename _Ty>
    struct mis_volatile<volatile _Ty>   {  static void ch() { printf("is
volatile: true\n"); }  };

template <typename _Ty>
    struct mis_pointer                  {  static void ch() { printf("is
pointer:  false\n"); }  };

template <typename _Ty>
    struct mis_pointer<_Ty *>           {  static void ch() { printf("is
pointer:  true\n"); }  };


template <typename _T>
    void show(_T t)
    {        
        printf("----------_T------------\n");
        mis_const<_T>::ch();
        mis_volatile<_T>::ch();
        mis_pointer<_T>::ch();


        printf("------decltype(t)-------\n");
        mis_const<decltype(t)>::ch();
        mis_volatile<decltype(t)>::ch();
        mis_pointer<decltype(t)>::ch();
    }

int main()
{
    const volatile int *g {nullptr};

    show(g);

    return 0;
}

// Console output:
// ----------_T------------
// is const:    false      error: not const.
// is volatile: false      error: not volatile.
// is pointer:  true       It's ok?
// ------decltype(t)-------
// is const:    false
// is volatile: false
// is pointer:  true