Re: c++/7678: implicity typename deprecated inheritance problem

Re: c++/7678: implicity typename deprecated inheritance problem

[nathan]

Synopsis: implicity typename deprecated inheritance problem

State-Changed-From-To: open->closed
State-Changed-By: nathan
State-Changed-When: Wed Aug 21 13:25:50 2002
State-Changed-Why:
    yes, our interpretation is correct.
    consider: when instantiated the base class might be
    an explicit specialization where size_type is something
    else.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7678

Re: c++/7678: implicity typename deprecated inheritance problem

[Gabriel Dos Reis]

The following reply was made to PR c++/7678; it has been noted by GNATS.

From: Gabriel Dos Reis <gdr@integrable-solutions.net>
To: dl256@columbia.edu
Cc: gcc-gnats@gcc.gnu.org
Subject: Re: c++/7678: implicity typename deprecated inheritance problem
Date: 23 Aug 2002 01:07:31 +0200

 dl256@columbia.edu writes:
 
 | g++ -c experiment.cpp
 
 The case you submitted is strictly speaking invalid -- that the
 warning should have been an error if g++ weren't supported the
 now-deprecated typename-extension.
 
 | The compiler warns that "implicit typname is deprecated".
 
 Yes, he is right.  In the first phase of name lookup, the scopes of
 dependent base classes are not examined,
 
 [...]
 
 | Is your interpretation of the specification correct for this case?
 
 Yes, it is.  You might consider fixing your code since that extension
 is deprecated and may disappear in future releases.
 
 -- Gaby

c++/7678: implicity typename deprecated inheritance problem

[dl256]

>Number:         7678
>Category:       c++
>Synopsis:       implicity typename deprecated inheritance problem
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Aug 21 10:06:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     dl256@columbia.edu
>Release:        gcc-3.1
>Organization:
>Environment:
gnu-linux kernal 2.4.18 (i686)
>Description:
compile the attached file using:

g++ -c experiment.cpp

The compiler warns that "implicit typname is deprecated".

.  The base class is templated.  It takes a traits structure as it's tmeplate argument, and then it creates typedefs in the public area of the class.  The derived class is also templated, but it contains no typedefs.  It is desirable to used the types defined in the base class in the derived class, without using the typename base<__traits>:: qualification.

Is your interpretation of the specification correct for this case? This doesn't make sense to me. The new types should at lease be inherited in the derived class so that we can use them in the usual way (i.e., without full qualification using typename).

>How-To-Repeat:
Just compile the attached file and check the warnings.
>Fix:
Don't know.
>Release-Note:
>Audit-Trail:
>Unformatted:
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