[Bug c++/34406] New: [reject valid?] incomplete type 'Y' used in nested name specifier.

[Bug c++/34406] New: [reject valid?] incomplete type 'Y' used in nested name specifier.

[pluto at agmk dot net]

template < typename T, typename C, C T::*F >
struct X
{
};

struct Y
{
        typedef X< Y, int, &Y::field_ > Z;
        int field_;
};

gcc-4.1 reports:
t.cpp:8: error: incomplete type 'Y' used in nested name specifier
t.cpp:8: error: template argument 3 is invalid

comeau online:
"ComeauTest.c", line 8: error: class "Y" has no member "field_"
        typedef X< Y, int, &Y::field_ > Z;

msvc8:
t.cpp(8) : error C2065: 'field_' : undeclared identifier

after moving the 'int field_' before typedef:
gcc and comeau accepts code, while msvc8 still rejects with:

t.cpp(9) : error C2327: 'Y::field_' : is not a type name, static, or enumerator
t.cpp(9) : error C2065: 'field_' : undeclared identifier

could someone throw some light please?


-- 
           Summary: [reject valid?] incomplete type 'Y' used in nested name
                    specifier.
           Product: gcc
           Version: 4.1.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pluto at agmk dot net


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34406

[Bug c++/34406] [reject valid?] incomplete type 'Y' used in nested name specifier.

[bangerth at dealii dot org]

------- Comment #1 from bangerth at dealii dot org  2008-01-13 02:33 -------
What is the question you want to ask? The first code you show is invalid,
the second valid...

W.


-- 

bangerth at dealii dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bangerth at dealii dot org
             Status|UNCONFIRMED                 |WAITING


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34406

[Bug c++/34406] [reject valid?] incomplete type 'Y' used in nested name specifier.

[pluto at agmk dot net]

------- Comment #2 from pluto at agmk dot net  2008-01-13 10:23 -------
(In reply to comment #1)
> What is the question you want to ask? The first code you show is invalid,
> the second valid...

i'd ask why the first code is invalid?
class Y looks pretty complete so why typedef expression throws an error?
could you please redirect me to the appropriate paragraph in c++ standard?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34406

[Bug c++/34406] [reject valid?] incomplete type 'Y' used in nested name specifier.

[bangerth at dealii dot org]

------- Comment #3 from bangerth at dealii dot org  2008-01-13 16:31 -------
(In reply to comment #2)
> i'd ask why the first code is invalid?
> class Y looks pretty complete so why typedef expression throws an error?

A class is complete at the closing brace. You use it before that.

W.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34406

[Bug c++/34406] [reject valid?] incomplete type 'Y' used in nested name specifier.

[pluto at agmk dot net]

------- Comment #4 from pluto at agmk dot net  2008-01-13 21:07 -------
invalid testcase.


-- 

pluto at agmk dot net changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34406