[Bug c++/27560] New: template function not recognized when invoked with enum defined in function

[Bug c++/27560] New: template function not recognized when invoked with enum defined in function

[ian at airs dot com]

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Compiling this file, with mainline, gcc 4.0, or 4.1

template<typename t> void f(t a) { }
void g() { enum e { v }; f(v); }

gives this error message:

foo.cc: In function ‘void g()’:
foo.cc:2: error: no matching function for call to ‘f(g()::e)’

If the enum definition is moved out of the function, this works.  With gcc 3.2,
this works.  I didn't try 3.4.

My C++ fu is weak, and I do not know for sure that this is valid C++, although
I don't see anything wrong with it.  But either 1) it is valid and gcc should
accept it, or 2) gcc should provide a list of candidates which did not match,
since there is manifestly a function named 'f'.


-- 
           Summary: template function not recognized when invoked with enum
                    defined in function
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ian at airs dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2006-05-11 15:58 -------
This is not valid, the type is a local type which causes it be rejected for
templates.  The same happens with local classes.


-- 

pinskia at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2006-05-11 16:07 -------
14.3.1/2
A local type, a type with no linkage, an unnamed type or a type compounded from
any of these types shall 
not be used as atemplate-argument for a template type-parameter.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[gdr at integrable-solutions dot net]

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------- Comment #3 from gdr at integrable-solutions dot net  2006-05-11 16:24 -------
Subject: Re:   New: template function not recognized when invoked with enum
defined in function

"ian at airs dot com" <gcc-bugzilla@gcc.gnu.org> writes:

| Compiling this file, with mainline, gcc 4.0, or 4.1
| 
| template<typename t> void f(t a) { }
| void g() { enum e { v }; f(v); }
| 
| gives this error message:
| 
| foo.cc: In function ‘void g()’:
| foo.cc:2: error: no matching function for call to ‘f(g()::e)’
| 
| If the enum definition is moved out of the function, this works.  With gcc
3.2,
| this works.  I didn't try 3.4.

There is a core issue for this.  We discussed it again at the last
meeting in Berlin.  There are proposals to make it "just work", but
that is still in the open state.

-- Gaby


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[gdr at gcc dot gnu dot org]

------- Comment #4 from gdr at gcc dot gnu dot org  2006-05-11 16:33 -------
See

   http://www.open-std.org/JTC1/SC22/WG21/docs/cwg_active.html#488
   http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2006/n1945.pdf

The later paper is under active consideration.

The PR should be suspended, instead of being hastly closed.


-- 

gdr at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |gdr at gcc dot gnu dot org
             Status|RESOLVED                    |UNCONFIRMED
         Resolution|INVALID                     |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[pinskia at gcc dot gnu dot org]

------- Comment #5 from pinskia at gcc dot gnu dot org  2006-05-11 16:38 -------
(In reply to comment #4)
> The PR should be suspended, instead of being hastly closed.

It was not hastly closed, the current standard says this is invalid.

Anyways there is already a PR open about DR 488.

*** This bug has been marked as a duplicate of 20589 ***


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |DUPLICATE


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[gdr at integrable-solutions dot net]

------- Comment #6 from gdr at integrable-solutions dot net  2006-05-11 16:47 -------
Subject: Re:  template function not recognized when invoked with enum defined
in function

"pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org> writes:

| It was not hastly closed, the current standard says this is invalid.

and the current standard is known to be defective in that aspect,
which is why we had the core issue in the first place. 

-- Gaby


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[ian at airs dot com]

------- Comment #7 from ian at airs dot com  2006-05-11 22:55 -------
PR 20589 seems to be about an unnamed enum.

This enum in this test case is not unnamed.  It is local to a function, but has
a name.

This may be related to 20589, but I don't think it is the same issue.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[pinskia at gcc dot gnu dot org]

------- Comment #8 from pinskia at gcc dot gnu dot org  2006-05-11 23:03 -------
(In reply to comment #7)
> This may be related to 20589, but I don't think it is the same issue.
It is the same issue because there is only one Defect report for the C++
standard.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[gdr at integrable-solutions dot net]

------- Comment #9 from gdr at integrable-solutions dot net  2006-05-11 23:20 -------
Subject: Re:  template function not recognized when invoked with enum defined
in function

"pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org> writes:

| (In reply to comment #7)
| > This may be related to 20589, but I don't think it is the same issue.
| It is the same issue because there is only one Defect report for the C++
| standard.

They are not the same thing. 

However, somehow, both issues have been conglomerated in the same
_topic_ 

-- Gaby


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560

[Bug c++/27560] template function not recognized when invoked with enum defined in function

[jason at gcc dot gnu dot org]

------- Comment #10 from jason at gcc dot gnu dot org  2009-11-04 20:16 -------
In 4.5 this will compile with -std=c++0x.


-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27560